Vulvodynia

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Mechanistic Hypotheses

1

Androgen-deprivation route to contraceptive-associated vestibulodynia

hormonal_vestibulodynia EMERGING

Evidence balance 1 support

That combined hormonal contraceptives precipitate vestibulodynia in women whose androgen receptor is already less efficient, by depriving the vestibular mucosa of androgen support. The genotype association has been observed in one small cohort; the accompanying hormone measurement ran in the wrong direction for the hypothesis, and no interventional or longitudinal test exists.

Pathograph links

Androgen Receptor Signalling Insufficiency -> Nociceptor Sensitization in the Vestibular Epithelium INDIRECT UNKNOWN INTERMEDIATES Androgen-dependent maintenance of the vestibular mucosa is the proposed route by which contraceptive exposure lowers the nociceptive threshold, on this hypothesis.

Show evidence (1 reference)

PMID:25187224 SUPPORT INDIRECT Human Clinical

"We speculate that the risk of developing CHC-induced vestibulodynia may be due to lowered free testosterone combined with an inefficient AR that predisposes women to vestibular pain."

This is the authors' own statement of the hypothesis, and is labelled as speculation in the source; graded INDIRECT for that reason.

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Discussions and Knowledge Gaps

4

Do mast cells contribute to vestibular pain in vulvodynia, or is the reported mast cell excess an artefact of case selection and unmatched controls?

CONTROVERSY OPEN mast_cell_contribution

Attached to

pathophysiology#Vestibular Mucosal Immune Activation

A 35-specimen series reports mast cell densities several-fold above control tissue and interprets them as a secondary hyperplasia reflecting an activated immune system. A larger case-control study of 100 confirmed cases with racially matched controls, using blinded c-KIT counting, finds no difference at all - and additionally shows mast cell density varies by race in controls, which is a plausible confounder for the earlier positive reports. Both are recorded on the node. Resolving this matters practically, because mast cell-directed therapy is proposed on the strength of the positive finding.

Why do the drug treatments most often prescribed for vulvodynia fail against placebo when the peripheral mechanism they target is well documented?

KNOWLEDGE GAP OPEN negative_trial_base

Attached to

treatments#Topical Lidocaine treatments#Oral Desipramine treatments#Oral Gabapentin pathophysiology#Nociceptor Sensitization in the Vestibular Epithelium

Every arm of the desipramine and lidocaine trial, including double placebo, reported substantial pain reduction, and the trial's own conclusion attributes the improvement to placebo or placebo-independent effects. The separate gabapentin crossover trial then returned the same answer for a third drug, on the same tampon-test endpoint. That is compatible with the drugs being ineffective, with the tampon test being insensitive to the change they produce, or with the disorder having a strong natural-history component over the trial period. The pooled analysis of four randomized trials covers only five interventions in 275 women in total, so the evidence base cannot currently distinguish these. That the same endpoint carries all three negative results is itself part of the question. The contrast with the one positive placebo-controlled result in this entry is suggestive rather than decisive: botulinum toxin acts on the pelvic floor node, not on the mucosal nociceptor node all three drugs are aimed at, which would be consistent with the peripheral mucosal target being the wrong one to drug - but it is a single trial on a different endpoint.

Show evidence (1 reference)

PMID:20733439 SUPPORT DIRECT Human Clinical

"Placebo or placebo-independent effects are behind the substantial pain improvement seen in all treatment allocations."

The trialists' own account of what produced the improvement, which is the observation this gap is about.

Does central pain amplification in vulvodynia follow sustained vestibular nociceptive input, or does it precede and predispose to it?

OPEN QUESTION OPEN central_versus_peripheral_order

Attached to

pathophysiology#Central Pain Amplification pathophysiology#Nociceptor Sensitization in the Vestibular Epithelium

The generalized pressure pain hypersensitivity was measured cross-sectionally and was equally present in localized and generalized presentations, which is hard to reconcile with it being purely a consequence of vestibular input. The edge drawn from the nociceptor node to the central node in this entry is therefore recorded as INDIRECT_UNKNOWN_INTERMEDIATES and the central node as PROVISIONAL. A prospective cohort measuring remote pain thresholds before onset would settle it.

Are anxiety and depression in vulvodynia consequences of the pain, factors that predispose to and maintain it, or both?

OPEN QUESTION OPEN psychological_factor_direction

Attached to

phenotypes#Anxiety phenotypes#Depression pathophysiology#Central Pain Amplification

The only source this entry has for the association names anxiety and depression among the factors involved in onset and maintenance, in one list with central pain mechanisms and cognitive-affective factors. That sentence asserts an interplay and deliberately does not separate cause from consequence, so an edge in either direction over-reads it. The pathograph draws them as consequences of the central amplification node, which follows this knowledge base's convention for psychiatric phenotypes and matches the node the cognitive behavioural therapy record targets, but that choice is a modelling decision and not a finding. Settling it needs a longitudinal cohort with psychiatric measures before onset; the same design would settle the central_versus_peripheral_order question.

Show evidence (1 reference)

PMID:32355269 SUPPORT INDIRECT Human Clinical

"Future efforts should aim to increase girls', women's and healthcare professionals' education and awareness of vulvodynia, phenotype different subgroups of women based on biopsychosocial characteristics among more diverse samples, conduct longitudinal studies and improve clinical trial designs."

The review's own call for longitudinal studies, which is the design this question needs; graded INDIRECT because it states the gap in research design rather than the direction of the association.

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Pathophysiology

9

Antecedent Vulvovaginal Inflammatory Exposure

Most women with localized provoked vulvodynia report preceding recurrent vulvovaginal candidiasis or other lower genital tract inflammation. The exposure is not itself the disease - most women with recurrent candidiasis do not develop vulvodynia - and the pathway below is what converts a common antecedent into persistent pain in a susceptible host.

mucosal inflammatory response GO:0006954 ↑ INCREASED

vulva UBERON:0000997

Downstream

Vestibular Fibroblast Innate Hyperresponsiveness Yeast and yeast cell wall glucan are the stimuli to which the vestibular fibroblast response is exaggerated, so the antecedent exposure is the trigger that the site-specific defect acts on.

Vestibular Mucosal Immune Activation Repeated mucosal infection is the most commonly proposed route to the lymphocytic infiltration and germinal centre formation seen in vestibular biopsies, although the temporal order has not been observed directly in humans.

Show evidence (1 reference)

PMID:25683963 SUPPORT INDIRECT In Vitro

"We then examined intracellular mechanisms by which these fibroblasts recognize pathogenic Candida albicans; >70% of vulvodynia patients report the occurrence of prior chronic Candida infections, which is accompanied by localized inflammation and elevated production of..."

States the frequency of antecedent chronic Candida infection in this population and the inflammatory mediators that accompany it. Graded INDIRECT because the figure is reported as background to an in vitro study rather than measured in it.

Vestibular Fibroblast Innate Hyperresponsiveness

Mechanism confidence: Established

Fibroblasts cultured from the vulvar vestibule - but not from external vulvar skin of the same women - respond to Candida species and to zymosan with high output of IL-6 and prostaglandin E2. The receptor is Dectin-1, whose abundance is highest in vestibular cells from cases, and the signal runs through NF-kB: blocking either arm abolishes most of the mediator release. The response is quantitatively linked to pain, since mediator production by a strain predicted the mechanical pain threshold measured at the site the strain was taken from.

vestibular fibroblast CL:0000057

Dectin-1 pattern recognition receptor signaling GO:0002221 ↑ INCREASED NF-kappaB-dependent proinflammatory transcription GO:0043123 ↑ INCREASED interleukin-6 production GO:0032635 ↑ INCREASED prostaglandin E2 biosynthesis GO:0001516 ↑ INCREASED

Downstream

Vestibular Mucosal Immune Activation IL-6 and PGE2 released by the resident fibroblast compartment recruit and sustain the mucosal immune infiltrate.

Vestibular Mucosal Neuroproliferation Sustained local prostaglandin and cytokine signalling is the proposed neurotrophic environment in which epithelial nerve fibres proliferate.

Show evidence (3 references)

PMID:25683963 SUPPORT DIRECT In Vitro

"Dectin-1, a surface receptor that binds C albicans cell wall glucan, was significantly elevated in vestibular vs external vulvar cells (from areas without pain) in both cases and controls, while its abundance was highest in LPV cases."

Establishes both the site-restriction of the receptor and its further elevation in cases, which is what makes the mechanism vestibule-specific rather than generalized.

PMID:25683963 SUPPORT DIRECT In Vitro

"Blocking Dectin-1 signaling significantly reduced pain-associated IL-6 and PGE2 production during the response to C albicans."

Interventional evidence that Dectin-1 is required for the mediator output, not merely correlated with it.

PMID:25679469 SUPPORT DIRECT In Vitro

"After C albicans and C glabrata challenge of all 16 fibroblast strains, adjusting for dual sampling of subjects, PGE2 and IL-6 production significantly predicted the presampling pain threshold from the genital tract site of sampling."

Links the in vitro mediator output quantitatively to the mechanical pain threshold measured at the same anatomical site, which is the step that connects this node to the clinical phenotype.

Vestibular Mucosal Immune Activation

Vestibular mucosa in provoked vestibulodynia carries organized secondary lymphoid tissue: dense B-cell infiltrates, germinal centres, and nerve growth factor-expressing immune cells clustered in the same areas. Whether mast cells are a part of this picture is genuinely disputed, and both results are recorded below rather than one being selected.

infiltrating B lymphocyte CL:0000236 mucosal mast cell CL:0000097

local mucosal inflammatory response GO:0006954 ↑ INCREASED

Downstream

Vestibular Mucosal Neuroproliferation Nerve growth factor-expressing immune cells sit in the same mucosal areas as the excess intraepithelial fibres, and fibre density tracks the intensity of B-cell activation.

Show evidence (3 references)

PMID:27457118 SUPPORT DIRECT Human Clinical

"Nerve growth factor-positive immune cells were more common in mucosal areas with than without B-cell infiltration and intraepithelial nerve fibers."

Places the neurotrophic source inside the B-cell infiltrate, which is what makes this node upstream of the neuroproliferation node rather than a parallel finding.

PMID:25912132 SUPPORT DIRECT Human Clinical

"4/35 biopsies showed <10 mast cells/mm(2) , 15/35 specimens 40-60 mast cells/mm(2) and 16/35 specimens >60 mast cells/mm(2) (average 80/mm(2) ). Control tissue contained typically <10 mast cells/mm(2) ."

Reports mast cell densities in vulvodynia specimens well above the control range quoted in the same passage, supporting a mast cell component.

PMID:27224531 REFUTE DIRECT Human Clinical

"There was no difference in the mast cell count between racially matched cases (22.4 ± 13.9 per ×400 field) and controls (22.5 ± 13.2) in either the univariate or multivariable analyses."

A larger case-control study with matched controls and blinded counting finds no mast cell excess, directly contradicting the mast cell arm of this node. Recorded rather than discarded; see the mast_cell_contribution discussion.

Vestibular Mucosal Neuroproliferation

Mechanism confidence: Established

Intraepithelial nerve fibre density in the vestibular mucosa is roughly three-fold higher than in controls, and neurofilament-positive intraepithelial fibres - absent from every control specimen examined - are present in about two-thirds of cases. Fibre density rises with the intensity of local B-cell activation, tying the excess innervation to the inflammatory node above it rather than making it an independent finding.

vestibular nociceptive fibre CL:0000198

epithelial nerve fibre outgrowth GO:0031175 ↑ INCREASED

vulva UBERON:0000997

Downstream

Nociceptor Sensitization in the Vestibular Epithelium A denser nociceptive innervation is the substrate on which the receptor changes below act.

Show evidence (2 references)

PMID:27457118 SUPPORT DIRECT Human Clinical

"We found more protein gene product 9.5-positive intraepithelial fibers in vestibulodynia than in the control samples"

States the excess intraepithelial innervation against controls. The quoted clause stops before the parenthetical figures (6.3/mm vs 2.0/mm; P=.006) because the bracketed ranges inside it are stripped by snippet matching; the numbers are in the same sentence of the cached record.

PMID:27457118 SUPPORT DIRECT Human Clinical

"The density of these fibers was higher in samples with than without germinal centers"

Couples fibre density to germinal centre formation, which is the specific link this edge from the immune node asserts.

Nociceptor Sensitization in the Vestibular Epithelium

Beyond the number of fibres, the fibres present are phenotypically shifted toward nociception: papillary TRPV1 (vanilloid receptor VR1) immunoreactivity is increased, both absolutely and as a proportion of the pan-neuronal marker PGP 9.5. Notably the same study found Nav1.8 fibres scarce in both cases and controls, so the sensitization is not a voltage-gated sodium channel story here.

vestibular nociceptive fibre CL:0000198

sensory perception of pain GO:0019233 ↑ INCREASED

Downstream

Vestibular Allodynia A sensitized, TRPV1-enriched nociceptor population in the vestibular epithelium is the proximate cause of pain on ordinarily innocuous contact.

Vulvar Burning Pain TRPV1 is triggered by noxious heat, protons and inflammatory mediators as well as by mechanical context, so a TRPV1-enriched nociceptor population is the proposed origin of the burning quality of the pain, including the component present outside contact. Recorded as indirect because the source offers it as a hypothesis rather than a measured link.

Central Pain Amplification Sustained peripheral nociceptive input from the vestibule is the conventional route to the generalized pressure pain hypersensitivity measured outside the pelvis, though the direction of causation has not been established in this disorder.

Show evidence (2 references)

PMID:14987622 SUPPORT DIRECT Human Clinical

"In the present study we show increased papillary VR1 fibres by immunostaining and image analysis in vulvodynia tissues compared to controls (p<0.002). VR1 expression was found to be significantly increased when the percentage area immunostained was expressed as a ratio of VR1 to PGP 9.5, a..."

Shows the receptor shift is disproportionate to the increase in total innervation, which is what distinguishes sensitization from more fibres alone.

PMID:14987622 NO_EVIDENCE DIRECT Human Clinical

"Fibres immunoreactive to the voltage-gated sodium channel SNS1/PN3 (Nav1.8), also expressed by nociceptors, were relatively scarce in both vulvodynia and control tissues."

Recorded as NO_EVIDENCE for a sodium-channel contribution at this node: the measurement was made and found nothing to distinguish cases from controls, which is why this entry does not conform to the nociceptor_sodium_channel_excitability module.

Vestibular Allodynia

Pain on light touch confined to the vulvar vestibule, elicited clinically by the cotton-swab test and quantified experimentally by lowered vulvar pressure pain thresholds. This is the cardinal objective sign of the localized form and is the node every treatment in this entry is ultimately aimed at.

Downstream

Provoked Vestibular Pain The allodynia measured by quantitative sensory testing is the same phenomenon the patient reports as contact-provoked vestibular pain and the examiner elicits with the cotton swab; this edge connects the measured sign to the presenting symptom.

Dyspareunia Vestibular contact during vaginal penetration is the commonest provoking stimulus, which is why the presenting complaint is usually pain with intercourse rather than pain at rest.

Pelvic Floor Muscle Hypertonicity Repeated painful penetration attempts elicit protective guarding of the pelvic floor, which becomes sustained.

Show evidence (1 reference)

PMID:15229011 SUPPORT DIRECT Human Clinical

"Pain thresholds at all vulvar locations were lower in the women with vulvodynia than in pain-free control subjects."

Instrumented confirmation of vulvar allodynia against pain-free controls, independent of the subjective swab test.

Pelvic Floor Muscle Hypertonicity

Women with provoked vestibulodynia show a smaller levator hiatus area, a smaller anorectal angle and a larger levator plate angle at rest, together indicating raised resting pelvic floor muscle tone, and they generate smaller changes on maximal contraction, indicating reduced strength and control. The measurement was made by transperineal ultrasound without vaginal insertion, which matters: earlier work using intravaginal instruments could not separate genuine hypertonicity from a reaction to the painful measurement itself.

levator ani muscle UBERON:0001326

Downstream

Dyspareunia Raised resting tone and impaired voluntary relaxation narrow the introitus and add a muscular component to penetration pain that is separable from the mucosal one.

Show evidence (2 references)

PMID:24344835 SUPPORT DIRECT Human Clinical

"Women with PVD showed a significantly smaller levator hiatus area, a smaller anorectal angle, and a larger levator plate angle at rest compared with asymptomatic women, suggesting an increase in PFM tone."

Direct morphometric evidence of raised resting tone in a nulliparous case-control sample, obtained by a pain-free method.

PMID:24344835 SUPPORT DIRECT Human Clinical

"During PFM maximal contraction, smaller changes in levator hiatus area narrowing, displacement of the bladder neck, and changes of the anorectal and of the levator plate angles were found in women with PVD compared with controls, which may indicate poorer PFM strength and control."

Adds the contractile deficit, which is the specific target of pelvic floor physical therapy in this entry.

Central Pain Amplification

Mechanism confidence: Provisional

Pressure pain thresholds are lowered not only at the vulva but at the thumb, deltoid and shin, and equally so in localized and generalized presentations. That distribution cannot be explained by vestibular pathology and points to altered central pain processing. It is recorded as PROVISIONAL because the observation is cross-sectional: whether central amplification follows sustained vestibular input, precedes it as a predisposition, or both, is not established.

sensory perception of pain GO:0019233 ↑ INCREASED

Downstream

Widespread Pressure Pain Hypersensitivity The generalized lowering of pressure pain thresholds is the measurable expression of this node outside the pelvis.

Anxiety Drawn from the central node rather than from the vestibular ones because the disease-specific review names anxiety alongside central pain mechanisms as part of one interplay, and because this is the node the entry's cognitive behavioural therapy record targets. The source describes onset and maintenance together, so it does not fix the direction; the edge records the direction the pathograph can carry and says the intermediates are unknown. See the psychological_factor_direction discussion.

Depression Same reasoning as the anxiety edge, resting on the same sentence naming depression among the factors involved in onset and maintenance.

Show evidence (2 references)

PMID:15229011 SUPPORT DIRECT Human Clinical

"Women with vulvodynia displayed significantly increased pressure pain sensitivity in both the vulvar region and in peripheral body regions, suggesting a "central" component to the mechanisms mediating this disorder."

The extra-pelvic distribution of the sensitivity is the observation this node rests on.

PMID:24807511 SUPPORT INDIRECT Human Clinical

"Women with vestibulodynia are likely to have other additional pain conditions, such as fibromyalgia, irritable bowel syndrome or chronic fatigue syndrome."

Clustering with other chronic overlapping pain conditions is consistent with a shared central mechanism; graded INDIRECT because comorbidity does not by itself demonstrate altered central processing.

Androgen Receptor Signalling Insufficiency

Mechanism confidence: Hypothetical

In women who developed vestibulodynia while taking combined hormonal contraceptives, androgen receptor CAG repeat lengths were longer than in women taking the same contraceptives without developing pain, and calculated free testosterone was higher rather than lower in the affected group. The proposed mechanism - a less efficient receptor combined with contraceptive suppression of free androgen leaving vestibular tissue androgen-deprived - is the authors' speculation, and the free testosterone result does not run in the direction that hypothesis predicts. Recorded as HYPOTHETICAL on a sample of 30 cases and 17 controls.

Androgen-deprivation route to contraceptive-associated vestibulodynia

AR hgnc:644

Downstream

Nociceptor Sensitization in the Vestibular Epithelium Androgen-dependent maintenance of the vestibular mucosa is the proposed route by which contraceptive exposure lowers the nociceptive threshold, on this hypothesis.

Show evidence (2 references)

PMID:25187224 SUPPORT DIRECT Human Clinical

"The mean number of CAG repeats in the study group was significantly greater than the control group (22.05 ± 2.98 vs. 20.61 ± 2.19, respectively; P = 0.025)."

The genotype difference between contraceptive-exposed women who did and did not develop vestibulodynia is the finding this node rests on.

PMID:25187224 REFUTE INDIRECT Human Clinical

"Among those who were taking drospirenone-containing CHCs, the mean calculated free testosterone was 0.189 ± 0.115 ng/dL in the study group and 0.127 ± 0.054 ng/dL in the control group, all of whom were taking drospirenone-containing CHCs (P = 0.042)."

Free testosterone was higher in cases, which is the opposite of what an androgen-deprivation mechanism predicts; recorded against this node rather than omitted.

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Pathograph

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Phenotypes

6

Genitourinary 1

Dyspareunia HP:0030016

Temporal: CHRONIC

Show evidence (1 reference)

PMID:25679469 SUPPORT DIRECT Human Clinical

"The most common cause of premenopausal, chronic intercourse pain (dyspareunia) is localized provoked vulvodynia (LPV)"

States the relationship between this disorder and dyspareunia in the premenopausal population.

Nervous System 2

Anxiety HP:0000739

Show evidence (1 reference)

PMID:32355269 SUPPORT DIRECT Human Clinical

"The onset and maintenance of vulvodynia involves a complex interplay of peripheral and central pain mechanisms, pelvic floor muscle and autonomic dysfunction, anxiety, depression and childhood maltreatment as well as cognitive-affective, behavioural and interpersonal factors."

Names anxiety among the factors involved in onset and maintenance.

Depression HP:0000716

Show evidence (1 reference)

PMID:32355269 SUPPORT DIRECT Human Clinical

"The onset and maintenance of vulvodynia involves a complex interplay of peripheral and central pain mechanisms, pelvic floor muscle and autonomic dysfunction, anxiety, depression and childhood maltreatment as well as cognitive-affective, behavioural and interpersonal factors."

Names depression among the factors involved in onset and maintenance.

Constitutional 3

Provoked Vestibular Pain Vulvodynia HP:0030943

Temporal: CHRONIC

Show evidence (1 reference)

PMID:32355269 SUPPORT DIRECT Human Clinical

"Diagnosis is established through careful medical history and pelvic examination, including the cotton-swab test."

Names the examination manoeuvre that elicits and localizes this phenotype.

Vulvar Burning Pain Vulvodynia HP:0030943

Temporal: CHRONIC

Show evidence (1 reference)

PMID:21963307 SUPPORT DIRECT Human Clinical

"Vulvodynia is a chronic pain condition associated with local hypersensitivity of the vulva that may be provoked (e.g., intercourse or tampon use), unprovoked (spontaneous), or both."

Establishes that the pain occurs in provoked, unprovoked and mixed forms, which is why this phenotype is recorded separately from the provoked one.

Widespread Pressure Pain Hypersensitivity Allodynia HP:0012533

Show evidence (1 reference)

PMID:15229011 SUPPORT DIRECT Human Clinical

"Similarly, peripheral pain thresholds were lower at the thumb in women with vulvodynia when obtained by discrete ascending or random staircase paradigms, as well as at the thumb, deltoid, and shin when tested by dolorimeter (P <.05)."

Gives the remote body sites and the testing paradigms behind this phenotype.

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Genetic Associations

2

IL1RN

Gene: IL1RN hgnc:6000 relationship_type: SUSCEPTIBILITY

Show evidence (1 reference)

PMID:10694325 SUPPORT DIRECT Human Clinical

"Allele 2 of the gene encoding the interleukin 1 receptor antagonist was present in homozygous form in 52.9% of women with vulvar vestibulitis. In marked contrast only 8. 5% of the control women and 2.5% of women with human papillomavirus were homozygous for this allele (P </=.0001)."

Gives the genotype frequencies in cases and both control groups that the susceptibility claim rests on.

AR

Gene: AR hgnc:644 relationship_type: SUSCEPTIBILITY

Show evidence (1 reference)

PMID:25187224 SUPPORT DIRECT Human Clinical

"In the study cohort, women who developed vestibulodynia while taking CHCs are more likely to have longer CAG repeats in the AR than women who took the same type of CHC but did not develop vestibulodynia."

States the gene-by-exposure association, including the exposure-matched comparison group that makes it a susceptibility rather than a main effect.

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Medical Actions

7

Pelvic Floor Physical Therapy

Action: pelvic floor muscle physical therapy Ontology label: Physical Therapy NCIT:C15302

Platform: Behavioral / lifestyle

Multimodal pelvic floor muscle physical therapy - biofeedback, manual therapy, dilators, electrical stimulation and education - aimed at the raised resting tone and impaired contractile control documented above. It is a first-line recommendation in clinical guidelines, but the supporting literature is dominated by uncontrolled designs.

Mechanism Target:

Pelvic Floor Muscle Hypertonicity — The modality acts on the muscular node directly, by retraining resting tone and voluntary relaxation.

Show evidence (2 references)

PMID:28363763 SUPPORT DIRECT Human Clinical

"The vast majority of studies showed that physical therapy modalities such as biofeedback, dilators, electrical stimulation, education, multimodal physical therapy, and multidisciplinary approaches were effective for decreasing pain during intercourse and improving sexual function."

Systematic review finding of benefit across 43 studies, which is the basis for first-line use.

PMID:28363763 SUPPORT INDIRECT Human Clinical

"Most studies had a high risk of bias mainly associated with the lack of a comparison group."

Recorded alongside the benefit claim because it is the same review's assessment of how much weight that claim can carry; graded INDIRECT because it bears on the strength of the recommendation rather than asserting it.

Cognitive Behavioural Therapy

Action: cognitive behavioural therapy Ontology label: Cognitive Behavior Therapy NCIT:C64345

Platform: Behavioral / lifestyle

Pain-focused cognitive behavioural therapy, recommended in a stepwise approach alongside pelvic floor physical therapy. It targets the cognitive-affective and behavioural factors named in disease-specific reviews as maintaining the pain, and the central amplification node.

Mechanism Target:

Central Pain Amplification — The intervention addresses the cognitive-affective and behavioural contribution to pain maintenance rather than the vestibular mucosa.

Show evidence (1 reference)

PMID:32355269 SUPPORT DIRECT Human Clinical

"Given the absence of empirically supported treatment guidelines, a stepwise approach of pelvic floor physical therapy and cognitive behavioural therapy as well as medical management is suggested, with surgery as the last option."

States the recommended position of this modality, and in the same sentence that the guideline base is not empirically supported.

Topical Lidocaine

Action: Pharmacotherapy NCIT:C15986

Agent: lidocaine CHEBI:6456

Platform: Small molecule

Topical 5% lidocaine applied to the vestibule, intended to block the sensitized mucocutaneous nerve endings directly. Widely used empirically; it did not outperform placebo cream in the one adequately powered randomized trial, and a subsequent network meta-analysis found no dyspareunia benefit.

Mechanism Target:

Nociceptor Sensitization in the Vestibular Epithelium — Sodium channel blockade at mucocutaneous nerve endings is the intended peripheral action, whatever its measured efficacy.

Show evidence (2 references)

PMID:20733439 REFUTE DIRECT Human Clinical

"Oral desipramine and topical lidocaine, as monotherapy or in combination, failed to reduce vulvodynia pain more than placebo."

The trial's primary conclusion refutes efficacy for pain reduction over placebo.

PMID:31364893 REFUTE DIRECT Human Clinical

"In traditional MA, interventions did not reduce dyspareunia (MD = 0.08; 95%CI = -0.49 to 0.64), DVS (MD = -0.04; 95%CI = -0.31 to 0.24; 4 interventions), or MPQ (MD = -0.17; 95%CI = -2.16 to 1.81; 4 interventions)."

Pooled result across the randomized evidence, including topical lidocaine, showing no dyspareunia benefit.

Oral Desipramine

Action: Pharmacotherapy NCIT:C15986

Agent: desipramine CHEBI:47781

Platform: Small molecule

A secondary-amine tricyclic antidepressant given orally for its central antinociceptive action at the spinal dorsal horn. It failed to reduce pain more than placebo in the randomized trial, but improved sexual satisfaction - the one secondary endpoint of thirteen that separated from placebo, and a result the later network meta-analysis reproduced.

Mechanism Target:

Central Pain Amplification — Tricyclic antidepressants are given here for their action on central pain modulation rather than on the vestibular mucosa.

Show evidence (3 references)

PMID:20733439 REFUTE DIRECT Human Clinical

"Compared with placebo, we found no significant difference in tampon-test pain reduction with desipramine (t=0.90; P=.37) or lidocaine (t=1.27; P=.21)."

The primary-endpoint comparison refutes a pain-reduction effect for desipramine.

PMID:20733439 SUPPORT DIRECT Human Clinical

"Of the remaining 12 outcome measures, only the Index of Sexual Satisfaction, improved with desipramine compared with placebo (t=-2.81; P=.006)."

A separate sentence reporting the one secondary endpoint that did favour desipramine; recorded as its own item because it supports a different claim from the refuting one above.

PMID:31364893 SUPPORT DIRECT Human Clinical

"In NMA, oral desipramine with or without lidocaine significantly improved ISS vs. other treatments."

Independent pooled confirmation of the sexual-satisfaction benefit, which is the only outcome this drug has support for.

Electromyography-Guided Botulinum Toxin A Injection

Action: electromyography-guided botulinum toxin type A injection Ontology label: Botulinum Toxin Therapy NCIT:C157775

Agent: onabotulinum toxin A CHEBI:3160

Platform: Other

Onabotulinum toxin A injected into the superficial perineal muscles under electromyographic guidance, aimed at the pelvic floor hypertonicity arm rather than at the vestibular mucosa. It is the one intervention in this entry with a positive placebo-controlled randomized result: pain, quality of life and sexual function all separated from saline at three months in a 60-patient trial. The trialists read that as evidence that muscular dysfunction is itself a driver of the pain rather than only a reaction to it, which is a claim about the pathograph and not only about the drug.

Mechanism Target:

Pelvic Floor Muscle Hypertonicity — Chemodenervation of the superficial perineal muscles acts on the raised resting tone documented at this node; the electromyographic guidance is what selects the muscles to inject.

Show evidence (2 references)

PMID:41419152 SUPPORT DIRECT Human Clinical

"After 3 months, the pain visual analog scale decreased in the treated group to 5.04±0.61 vs 7.37±0.45 in the placebo group (P=.008)."

The primary-endpoint result against saline placebo, which is what distinguishes this treatment from the three drug records above.

PMID:41419152 SUPPORT INDIRECT Human Clinical

"We suggest that muscular dysfunction is a key element of vestibulodynia pain."

The trialists' mechanistic reading of their own result, cited here as therapeutic validation of the pelvic floor node; graded INDIRECT because the inference from treatment response to mechanism is an extra step.

Oral Gabapentin

Action: Pharmacotherapy NCIT:C15986

Agent: gabapentin CHEBI:42797

Platform: Small molecule

Extended-release gabapentin given orally for the neuropathic features of the disorder. It is commonly prescribed and appears in several vulvodynia treatment guidelines, but until 2018 no placebo-controlled randomized trial of it existed; when one was run it separated from placebo on none of the three pain outcomes, and its authors concluded against recommending gabapentin alone.

Mechanism Target:

Central Pain Amplification — Gabapentin is given here on the reasoning that vulvodynia behaves like a neuropathic pain state, so the intended action is on central pain processing rather than on the vestibular mucosa.

Show evidence (2 references)

PMID:29742655 SUPPORT INDIRECT Human Clinical

"Women with vulvodynia often present with certain neuropathic characteristics, such as dynamic allodynia (pain in response to light touch)."

States the rationale for using a neuropathic pain drug in this disorder, which is what this treatment record's mechanism target rests on; graded INDIRECT because it motivates the choice rather than demonstrating efficacy.

PMID:29742655 REFUTE DIRECT Human Clinical

"In this cohort, extended-release gabapentin, as compared with a placebo, did not reduce tampon test pain. These data do not support the recommendation of gabapentin alone as treatment for vulvodynia."

The trial's own conclusion refutes efficacy on the primary endpoint and refuses the guideline recommendation.

Vestibulectomy

Action: vestibulectomy Ontology label: Surgical Procedure NCIT:C15329

Platform: Surgery

Surgical excision of the painful vestibular mucosa, reserved for refractory localized provoked disease. It is the intervention with the largest reported effect, and it removes precisely the tissue in which the neuroproliferation and receptor changes above are found - the surgical specimens are in fact the source of most of that histological evidence. Long-term follow-up series are uncontrolled and subject to responder bias.

Mechanism Target:

Vestibular Mucosal Neuroproliferation — Excision removes the hyperinnervated vestibular mucosa itself, which is why the procedure is mechanistically coherent with the pathograph even where the trial evidence is weak.

Show evidence (2 references)

PMID:32569021 SUPPORT DIRECT Human Clinical

"Penetration pain averaged 9.13 (scale = 0-10) before surgery and dropped to 0.47 at the time of follow up (p < .001)."

Quantifies the pain reduction at 12-24 year follow-up in the reported series.

PMID:20733439 SUPPORT INDIRECT Human Clinical

"During the open-label phase, women undergoing vestibulectomy surgery reported significantly improved pain as measured by cotton swab test and the McGill Pain Scale compared with nonsurgical alternatives."

Supports surgical benefit from within the randomized trial's own cohort; graded INDIRECT because the comparison is open-label and non-randomized.

🌍

Environmental Factors

1

Combined hormonal contraceptive use

ECTO was searched for a contraceptive-exposure term and none was found, so exposure_term carries a free-text preferred_term with no binding rather than a stretched match.

Use of combined hormonal contraceptives preceding the onset of vestibular pain. The exposure is recorded here because it defines the cohort in which the androgen receptor association was found; it is a predisposing context on a specific genetic background rather than a demonstrated cause of vulvodynia in general.

Show evidence (1 reference)

PMID:25187224 SUPPORT DIRECT Human Clinical

"Women who developed vestibulodynia (vulvar vestibulitis) while taking combined hormonal contraceptives (CHCs) and a control group of women were tested for polymorphisms of the gene coding for the androgen receptor (AR) that is located on the X chromosome."

Establishes the exposure-defined case group this environmental record describes.

Mechanism Target:

PREDISPOSES Androgen Receptor Signalling Insufficiency — Contraceptive suppression of circulating free androgen is the exposure arm of the proposed gene-by-environment mechanism at this node.

Show evidence (1 reference)

PMID:25187224 SUPPORT INDIRECT Human Clinical

"We speculate that the risk of developing CHC-induced vestibulodynia may be due to lowered free testosterone combined with an inefficient AR that predisposes women to vestibular pain."

The authors' statement of how the exposure is proposed to act on androgen receptor signalling; graded INDIRECT because it is labelled speculation in the source.

🔬

Diagnosis

2

Cotton-swab test

Light pressure applied with a cotton swab at defined points of the vestibule, with the labia and lower vagina tested as internal negative controls. It localizes the allodynia and is the manoeuvre on which the localized provoked diagnosis rests.

Show evidence (1 reference)

PMID:32355269 SUPPORT DIRECT Human Clinical

"Diagnosis is established through careful medical history and pelvic examination, including the cotton-swab test."

Names the test as part of establishing the diagnosis.

Exclusion of identifiable vulvar disease

Vulvodynia is defined by the absence of a specific identifiable cause, so the diagnosis requires that infection, dermatosis and neurological disease have been looked for and not found. The 2015 tri-society terminology formalized this by separating vulvar pain caused by a specific disorder from vulvodynia.

Show evidence (1 reference)

PMID:27045260 SUPPORT DIRECT Other

"In 2015, the ISSVD, ISSWSH, and IPPS adopted a new vulvar pain and vulvodynia terminology that acknowledges the complexity of the clinical presentation and pathophysiology involved in vulvar pain and vulvodynia, and incorporates new information derived from evidence-based studies conducted since..."

Documents the consensus terminology that governs how this diagnosis is framed; graded OTHER because it reports an expert-consensus process rather than a study.

📊

Prevalence

2

Women aged 18-59, southeast Michigan, USA

Point Prevalence 8300.0 per 100,000 (7000.0–9800.0) >1 in 1,000

Weighted point prevalence from a population-based telephone-recruited survey with a validated screening instrument. Recorded as cases per 100,000 from the reported 8.3% (95% CI 7.0-9.8%).

Show evidence (1 reference)

PMID:21963307 SUPPORT DIRECT Human Clinical

"The weighted prevalence of vulvodynia was 8.3% (95% confidence interval, 7.0-9.8) or approximately 101,000 women in the targeted population."

Gives the weighted point-prevalence estimate and interval recorded in this record.

Women aged 18-64, five ethnically diverse Boston communities, USA

Lifetime Prevalence 16000.0 per 100,000 >1 in 1,000

Self-reported history of chronic vulvar burning, knife-like pain, or pain on contact lasting three months or more. The same survey found roughly 7% symptomatic at the time of the survey, so the lifetime and point figures are not interchangeable.

Show evidence (1 reference)

PMID:12744420 SUPPORT DIRECT Human Clinical

"Approximately 16% of respondents reported histories of chronic burning, knife like pain, or pain on contact that lasted for at least 3 months or longer, and nearly 7% were experiencing the problem at the time of the survey."

Reports the lifetime-history figure recorded here and, in the same sentence, the contemporaneous figure that distinguishes it from point prevalence.

🌍

Epidemiology

1

Co-occurring chronic overlapping pain conditions

Vulvodynia clusters with the other chronic overlapping pain conditions rather than occurring in isolation. Fibromyalgia, irritable bowel syndrome and chronic fatigue syndrome are the ones named for vestibulodynia specifically, and the bladder pain syndrome overlap is quantified: a quarter of women with bladder pain syndrome/interstitial cystitis also have vestibulodynia. This is a different claim from the differential diagnoses recorded below, which are conditions to be excluded before the diagnosis is made rather than conditions that accompany it.

fibromyalgia irritable bowel syndrome chronic fatigue syndrome bladder pain syndrome/interstitial cystitis

Recorded here rather than in a comorbidities section because the Disease class has no comorbidity slot; a two-disease association with its own statistics would be a separate kb/comorbidities/ entry. The 25% figure describes vestibulodynia among women with bladder pain syndrome, not the converse, and the review states it as a report of recent data rather than from a cohort it assembled.

Show evidence (3 references)

PMID:24807511 SUPPORT DIRECT Human Clinical

"Women with vestibulodynia are likely to have other additional pain conditions, such as fibromyalgia, irritable bowel syndrome or chronic fatigue syndrome."

Names the three co-occurring pain conditions recorded in the factors list.

PMID:24807511 SUPPORT DIRECT Human Clinical

"Recent data reported that vestibulodynia affects 25% of women with bladder pain syndrome/interstitial cystitis."

Quantifies the bladder pain syndrome overlap; recorded as its own item because it is a separate claim from the list of co-occurring pain conditions above.

PMID:32355269 SUPPORT DIRECT Human Clinical

"In addition, women with vulvodynia are more likely to report other chronic pain conditions, which further alters their quality of life."

Independent disease-specific review statement that the clustering is a property of vulvodynia generally, not only of the vestibulodynia subset.

⚖️

Clinical Burden

High

A common condition with a long symptomatic course that is rarely diagnosed: in a population-based sample fewer than 2% of women meeting criteria had ever received the diagnosis, and among those who sought care the majority consulted three or more clinicians without obtaining one. Pain is intercourse-limiting and is accompanied by anxiety, depression and relationship distress, with a documented personal and societal economic burden.

Show evidence (3 references)

PMID:21963307 SUPPORT DIRECT Human Clinical

"Of 208 women meeting vulvodynia criteria, 101 (48.6%) had sought treatment, and only 3 (1.4%) had been diagnosed with vulvodynia (unweighted values)."

Quantifies the diagnostic shortfall that drives much of the burden: under half sought care and 1.4% carried the diagnosis.

PMID:12744420 SUPPORT DIRECT Human Clinical

"Nearly 40% of women chose not to seek treatment, and of those who did, 60% saw 3 or more doctors, many of whom could not provide a diagnosis."

Independently documents the diagnostic odyssey component of the burden in a separate population-based sample.

PMID:32355269 SUPPORT DIRECT Human Clinical

"Vulvodynia has a negative effect on the quality of life of women and their partners, and imposes a profound personal and societal economic burden."

Disease-specific review statement of quality-of-life and economic burden.

🔀

Differential Diagnoses

3

Conditions with similar clinical presentations that must be differentiated from Vulvodynia:

Vulvovaginal candidiasis

Overlapping Features Active yeast infection produces vulvar burning and dyspareunia and must be excluded before the diagnosis is made; culture- or smear-proven Candida was an exclusion criterion in the randomized trial of this disorder.

Distinguishing Features

positive culture or microscopy for Candida species
response to antifungal treatment

Lichen sclerosus and other vulvar dermatoses

Overlapping Features Vulvar dermatoses cause chronic soreness with visible skin change; vulvodynia by definition has no such identifiable lesion.

Distinguishing Features

visible atrophic or sclerotic skin change on examination
diagnostic histopathology

Pudendal neuralgia

Overlapping Features A named neuropathy of the pudendal nerve, distinguished by a nerve-territory distribution extending beyond the vestibule.

Distinguishing Features

pain in the full pudendal nerve distribution rather than confined to the vestibule

{ }

Source YAML

click to show

name: Vulvodynia
creation_date: '2026-09-13T00:00:00Z'
description: >-
  Chronic vulvar pain of at least three months' duration with no identifiable
  specific cause, most often localized to the vulvar vestibule and provoked by
  touch. The best-evidenced mechanism is a site-restricted one: vestibular
  fibroblasts, uniquely among lower genital tract fibroblasts, mount an
  exaggerated Dectin-1/NF-kB innate response to yeast and yeast cell wall
  components, releasing IL-6 and prostaglandin E2. The resulting chronic mucosal
  inflammation, with B-cell infiltration and germinal centre formation, drives
  excessive intraepithelial nerve growth and an increase in TRPV1-expressing
  nociceptive fibres confined to the vestibule. Those sensitized fibres make
  ordinarily innocuous contact painful (provoked allodynia), which in turn
  recruits protective pelvic floor muscle hypertonicity and, in many women,
  central pain amplification detectable far outside the pelvis. The disorder is
  common and grossly underdiagnosed, and the three drugs most often prescribed
  for it - topical lidocaine, oral desipramine and oral gabapentin - each failed
  against placebo in an adequately powered randomized trial. The one
  placebo-controlled success recorded here acts on the muscular arm rather than
  the mucosal one.
category: Complex
parents:
- Reproductive Disease
- Chronic Pain Disorder
synonyms:
- vestibulodynia
- provoked vestibulodynia
- localized provoked vulvodynia
- vulvar vestibulitis syndrome
disease_term:
  preferred_term: vulvodynia
  term:
    id: MONDO:0021722
    label: vulvodynia
prevalence:
- population: Women aged 18-59, southeast Michigan, USA
  measure_type: POINT_PREVALENCE
  prevalence_class: ABOVE_1_IN_1000
  rate_per_100000: 8300.0
  rate_low: 7000.0
  rate_high: 9800.0
  notes: >-
    Weighted point prevalence from a population-based telephone-recruited survey
    with a validated screening instrument. Recorded as cases per 100,000 from the
    reported 8.3% (95% CI 7.0-9.8%).
  evidence:
  - reference: PMID:21963307
    reference_title: "Prevalence and demographic characteristics of vulvodynia in a population-based sample."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The weighted prevalence of vulvodynia was 8.3% (95% confidence interval, 7.0-9.8) or approximately 101,000 women in the targeted population.
    explanation: >-
      Gives the weighted point-prevalence estimate and interval recorded in this
      record.
- population: Women aged 18-64, five ethnically diverse Boston communities, USA
  measure_type: LIFETIME_PREVALENCE
  prevalence_class: ABOVE_1_IN_1000
  rate_per_100000: 16000.0
  notes: >-
    Self-reported history of chronic vulvar burning, knife-like pain, or pain on
    contact lasting three months or more. The same survey found roughly 7%
    symptomatic at the time of the survey, so the lifetime and point figures are
    not interchangeable.
  evidence:
  - reference: PMID:12744420
    reference_title: "A population-based assessment of chronic unexplained vulvar pain: have we underestimated the prevalence of vulvodynia?"
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Approximately 16% of respondents reported histories of chronic burning, knife like pain, or pain on contact that lasted for at least 3 months or longer, and nearly 7% were experiencing the problem at the time of the survey.
    explanation: >-
      Reports the lifetime-history figure recorded here and, in the same
      sentence, the contemporaneous figure that distinguishes it from point
      prevalence.
clinical_burden:
  burden_level: HIGH
  rationale: >-
    A common condition with a long symptomatic course that is rarely diagnosed:
    in a population-based sample fewer than 2% of women meeting criteria had ever
    received the diagnosis, and among those who sought care the majority
    consulted three or more clinicians without obtaining one. Pain is
    intercourse-limiting and is accompanied by anxiety, depression and
    relationship distress, with a documented personal and societal economic
    burden.
  evidence:
  - reference: PMID:21963307
    reference_title: "Prevalence and demographic characteristics of vulvodynia in a population-based sample."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Of 208 women meeting vulvodynia criteria, 101 (48.6%) had sought treatment, and only 3 (1.4%) had been diagnosed with vulvodynia (unweighted values).
    explanation: >-
      Quantifies the diagnostic shortfall that drives much of the burden: under
      half sought care and 1.4% carried the diagnosis.
  - reference: PMID:12744420
    reference_title: "A population-based assessment of chronic unexplained vulvar pain: have we underestimated the prevalence of vulvodynia?"
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Nearly 40% of women chose not to seek treatment, and of those who did, 60% saw 3 or more doctors, many of whom could not provide a diagnosis.
    explanation: >-
      Independently documents the diagnostic odyssey component of the burden in a
      separate population-based sample.
  - reference: PMID:32355269
    reference_title: "Vulvodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Vulvodynia has a negative effect on the quality of life of women and their partners, and imposes a profound personal and societal economic burden.
    explanation: >-
      Disease-specific review statement of quality-of-life and economic burden.
epidemiology:
- name: Co-occurring chronic overlapping pain conditions
  description: >-
    Vulvodynia clusters with the other chronic overlapping pain conditions rather
    than occurring in isolation. Fibromyalgia, irritable bowel syndrome and
    chronic fatigue syndrome are the ones named for vestibulodynia specifically,
    and the bladder pain syndrome overlap is quantified: a quarter of women with
    bladder pain syndrome/interstitial cystitis also have vestibulodynia. This is
    a different claim from the differential diagnoses recorded below, which are
    conditions to be excluded before the diagnosis is made rather than conditions
    that accompany it.
  factors:
  - fibromyalgia
  - irritable bowel syndrome
  - chronic fatigue syndrome
  - bladder pain syndrome/interstitial cystitis
  notes: >-
    Recorded here rather than in a comorbidities section because the Disease
    class has no comorbidity slot; a two-disease association with its own
    statistics would be a separate kb/comorbidities/ entry. The 25% figure
    describes vestibulodynia among women with bladder pain syndrome, not the
    converse, and the review states it as a report of recent data rather than
    from a cohort it assembled.
  evidence:
  - reference: PMID:24807511
    reference_title: "Gynecological disorders in bladder pain syndrome/interstitial cystitis patients."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Women with vestibulodynia are likely to have other additional pain conditions, such as fibromyalgia, irritable bowel syndrome or chronic fatigue syndrome.
    explanation: >-
      Names the three co-occurring pain conditions recorded in the factors list.
  - reference: PMID:24807511
    reference_title: "Gynecological disorders in bladder pain syndrome/interstitial cystitis patients."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Recent data reported that vestibulodynia affects 25% of women with bladder pain syndrome/interstitial cystitis.
    explanation: >-
      Quantifies the bladder pain syndrome overlap; recorded as its own item
      because it is a separate claim from the list of co-occurring pain
      conditions above.
  - reference: PMID:32355269
    reference_title: "Vulvodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In addition, women with vulvodynia are more likely to report other chronic pain conditions, which further alters their quality of life.
    explanation: >-
      Independent disease-specific review statement that the clustering is a
      property of vulvodynia generally, not only of the vestibulodynia subset.
pathophysiology:
- name: Antecedent Vulvovaginal Inflammatory Exposure
  biological_scale: TISSUE
  description: >-
    Most women with localized provoked vulvodynia report preceding recurrent
    vulvovaginal candidiasis or other lower genital tract inflammation. The
    exposure is not itself the disease - most women with recurrent candidiasis do
    not develop vulvodynia - and the pathway below is what converts a common
    antecedent into persistent pain in a susceptible host.
  locations:
  - preferred_term: vulva
    term:
      id: UBERON:0000997
      label: mammalian vulva
  biological_processes:
  - preferred_term: mucosal inflammatory response
    modifier: INCREASED
    term:
      id: GO:0006954
      label: inflammatory response
  evidence:
  - reference: PMID:25683963
    reference_title: "Identification of novel mechanisms involved in generating localized vulvodynia pain."
    supports: SUPPORT
    directness: INDIRECT
    evidence_source: IN_VITRO
    snippet: >-
      We then examined intracellular mechanisms by which these fibroblasts recognize pathogenic Candida albicans; >70% of vulvodynia patients report the occurrence of prior chronic Candida infections, which is accompanied by localized inflammation and elevated production of proinflammatory/pain-associated interleukin (IL)-6 and prostaglandin E2 (PGE2).
    explanation: >-
      States the frequency of antecedent chronic Candida infection in this
      population and the inflammatory mediators that accompany it. Graded
      INDIRECT because the figure is reported as background to an in vitro study
      rather than measured in it.
  downstream:
  - target: Vestibular Fibroblast Innate Hyperresponsiveness
    description: >-
      Yeast and yeast cell wall glucan are the stimuli to which the vestibular
      fibroblast response is exaggerated, so the antecedent exposure is the
      trigger that the site-specific defect acts on.
    causal_link_type: DIRECT
  - target: Vestibular Mucosal Immune Activation
    description: >-
      Repeated mucosal infection is the most commonly proposed route to the
      lymphocytic infiltration and germinal centre formation seen in vestibular
      biopsies, although the temporal order has not been observed directly in
      humans.
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
- name: Vestibular Fibroblast Innate Hyperresponsiveness
  biological_scale: CELLULAR
  mechanism_confidence: ESTABLISHED
  description: >-
    Fibroblasts cultured from the vulvar vestibule - but not from external vulvar
    skin of the same women - respond to Candida species and to zymosan with high
    output of IL-6 and prostaglandin E2. The receptor is Dectin-1, whose
    abundance is highest in vestibular cells from cases, and the signal runs
    through NF-kB: blocking either arm abolishes most of the mediator release.
    The response is quantitatively linked to pain, since mediator production by a
    strain predicted the mechanical pain threshold measured at the site the
    strain was taken from.
  cell_types:
  - preferred_term: vestibular fibroblast
    term:
      id: CL:0000057
      label: fibroblast
  biological_processes:
  - preferred_term: Dectin-1 pattern recognition receptor signaling
    modifier: INCREASED
    term:
      id: GO:0002221
      label: pattern recognition receptor signaling pathway
  - preferred_term: NF-kappaB-dependent proinflammatory transcription
    modifier: INCREASED
    term:
      id: GO:0043123
      label: positive regulation of canonical NF-kappaB signal transduction
  - preferred_term: interleukin-6 production
    modifier: INCREASED
    term:
      id: GO:0032635
      label: interleukin-6 production
  - preferred_term: prostaglandin E2 biosynthesis
    modifier: INCREASED
    term:
      id: GO:0001516
      label: prostaglandin biosynthetic process
  evidence:
  - reference: PMID:25683963
    reference_title: "Identification of novel mechanisms involved in generating localized vulvodynia pain."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: IN_VITRO
    snippet: >-
      Dectin-1, a surface receptor that binds C albicans cell wall glucan, was significantly elevated in vestibular vs external vulvar cells (from areas without pain) in both cases and controls, while its abundance was highest in LPV cases.
    explanation: >-
      Establishes both the site-restriction of the receptor and its further
      elevation in cases, which is what makes the mechanism vestibule-specific
      rather than generalized.
  - reference: PMID:25683963
    reference_title: "Identification of novel mechanisms involved in generating localized vulvodynia pain."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: IN_VITRO
    snippet: >-
      Blocking Dectin-1 signaling significantly reduced pain-associated IL-6 and PGE2 production during the response to C albicans.
    explanation: >-
      Interventional evidence that Dectin-1 is required for the mediator output,
      not merely correlated with it.
  - reference: PMID:25679469
    reference_title: "Site-specific mesenchymal control of inflammatory pain to yeast challenge in vulvodynia-afflicted and pain-free women."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: IN_VITRO
    snippet: >-
      After C albicans and C glabrata challenge of all 16 fibroblast strains, adjusting for dual sampling of subjects, PGE2 and IL-6 production significantly predicted the presampling pain threshold from the genital tract site of sampling.
    explanation: >-
      Links the in vitro mediator output quantitatively to the mechanical pain
      threshold measured at the same anatomical site, which is the step that
      connects this node to the clinical phenotype.
  downstream:
  - target: Vestibular Mucosal Immune Activation
    description: >-
      IL-6 and PGE2 released by the resident fibroblast compartment recruit and
      sustain the mucosal immune infiltrate.
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - IL-6-driven leucocyte recruitment and survival
    - prostaglandin E2 signalling on infiltrating immune cells
  - target: Vestibular Mucosal Neuroproliferation
    description: >-
      Sustained local prostaglandin and cytokine signalling is the proposed
      neurotrophic environment in which epithelial nerve fibres proliferate.
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
- name: Vestibular Mucosal Immune Activation
  biological_scale: TISSUE
  description: >-
    Vestibular mucosa in provoked vestibulodynia carries organized secondary
    lymphoid tissue: dense B-cell infiltrates, germinal centres, and nerve growth
    factor-expressing immune cells clustered in the same areas. Whether mast
    cells are a part of this picture is genuinely disputed, and both results are
    recorded below rather than one being selected.
  cell_types:
  - preferred_term: infiltrating B lymphocyte
    term:
      id: CL:0000236
      label: B cell
  - preferred_term: mucosal mast cell
    term:
      id: CL:0000097
      label: mast cell
  biological_processes:
  - preferred_term: local mucosal inflammatory response
    modifier: INCREASED
    term:
      id: GO:0006954
      label: inflammatory response
  evidence:
  - reference: PMID:27457118
    reference_title: "Immune activation enhances epithelial nerve growth in provoked vestibulodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Nerve growth factor-positive immune cells were more common in mucosal areas with than without B-cell infiltration and intraepithelial nerve fibers.
    explanation: >-
      Places the neurotrophic source inside the B-cell infiltrate, which is what
      makes this node upstream of the neuroproliferation node rather than a
      parallel finding.
  - reference: PMID:25912132
    reference_title: "Mast cell infiltrates in vulvodynia represent secondary and idiopathic mast cell hyperplasias."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      4/35 biopsies showed <10 mast cells/mm(2) , 15/35 specimens 40-60 mast cells/mm(2) and 16/35 specimens >60 mast cells/mm(2) (average 80/mm(2) ). Control tissue contained typically <10 mast cells/mm(2) .
    explanation: >-
      Reports mast cell densities in vulvodynia specimens well above the control
      range quoted in the same passage, supporting a mast cell component.
  - reference: PMID:27224531
    reference_title: "Vestibular Mast Cell Density in Vulvodynia: A Case-Controlled Study."
    supports: REFUTE
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      There was no difference in the mast cell count between racially matched cases (22.4 ± 13.9 per ×400 field) and controls (22.5 ± 13.2) in either the univariate or multivariable analyses.
    explanation: >-
      A larger case-control study with matched controls and blinded counting
      finds no mast cell excess, directly contradicting the mast cell arm of this
      node. Recorded rather than discarded; see the mast_cell_contribution
      discussion.
  downstream:
  - target: Vestibular Mucosal Neuroproliferation
    description: >-
      Nerve growth factor-expressing immune cells sit in the same mucosal areas
      as the excess intraepithelial fibres, and fibre density tracks the
      intensity of B-cell activation.
    causal_link_type: DIRECT
- name: Vestibular Mucosal Neuroproliferation
  biological_scale: TISSUE
  mechanism_confidence: ESTABLISHED
  description: >-
    Intraepithelial nerve fibre density in the vestibular mucosa is roughly
    three-fold higher than in controls, and neurofilament-positive
    intraepithelial fibres - absent from every control specimen examined - are
    present in about two-thirds of cases. Fibre density rises with the intensity
    of local B-cell activation, tying the excess innervation to the inflammatory
    node above it rather than making it an independent finding.
  locations:
  - preferred_term: vulva
    term:
      id: UBERON:0000997
      label: mammalian vulva
  cell_types:
  - preferred_term: vestibular nociceptive fibre
    term:
      id: CL:0000198
      label: pain receptor cell
  biological_processes:
  - preferred_term: epithelial nerve fibre outgrowth
    modifier: INCREASED
    term:
      id: GO:0031175
      label: neuron projection development
  evidence:
  - reference: PMID:27457118
    reference_title: "Immune activation enhances epithelial nerve growth in provoked vestibulodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      We found more protein gene product 9.5-positive intraepithelial fibers in vestibulodynia than in the control samples
    explanation: >-
      States the excess intraepithelial innervation against controls. The
      quoted clause stops before the parenthetical figures (6.3/mm vs 2.0/mm;
      P=.006) because the bracketed ranges inside it are stripped by snippet
      matching; the numbers are in the same sentence of the cached record.
  - reference: PMID:27457118
    reference_title: "Immune activation enhances epithelial nerve growth in provoked vestibulodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The density of these fibers was higher in samples with than without germinal centers
    explanation: >-
      Couples fibre density to germinal centre formation, which is the specific
      link this edge from the immune node asserts.
  downstream:
  - target: Nociceptor Sensitization in the Vestibular Epithelium
    description: >-
      A denser nociceptive innervation is the substrate on which the receptor
      changes below act.
    causal_link_type: DIRECT
- name: Nociceptor Sensitization in the Vestibular Epithelium
  biological_scale: CELLULAR
  description: >-
    Beyond the number of fibres, the fibres present are phenotypically shifted
    toward nociception: papillary TRPV1 (vanilloid receptor VR1) immunoreactivity
    is increased, both absolutely and as a proportion of the pan-neuronal marker
    PGP 9.5. Notably the same study found Nav1.8 fibres scarce in both cases and
    controls, so the sensitization is not a voltage-gated sodium channel story
    here.
  cell_types:
  - preferred_term: vestibular nociceptive fibre
    term:
      id: CL:0000198
      label: pain receptor cell
  biological_processes:
  - preferred_term: sensory perception of pain
    modifier: INCREASED
    term:
      id: GO:0019233
      label: sensory perception of pain
  evidence:
  - reference: PMID:14987622
    reference_title: "Increased vanilloid receptor VR1 innervation in vulvodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In the present study we show increased papillary VR1 fibres by immunostaining and image analysis in vulvodynia tissues compared to controls (p<0.002). VR1 expression was found to be significantly increased when the percentage area immunostained was expressed as a ratio of VR1 to PGP 9.5, a pan-neuronal marker (P=0.01).
    explanation: >-
      Shows the receptor shift is disproportionate to the increase in total
      innervation, which is what distinguishes sensitization from more fibres
      alone.
  - reference: PMID:14987622
    reference_title: "Increased vanilloid receptor VR1 innervation in vulvodynia."
    supports: NO_EVIDENCE
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Fibres immunoreactive to the voltage-gated sodium channel SNS1/PN3 (Nav1.8), also expressed by nociceptors, were relatively scarce in both vulvodynia and control tissues.
    explanation: >-
      Recorded as NO_EVIDENCE for a sodium-channel contribution at this node: the
      measurement was made and found nothing to distinguish cases from controls,
      which is why this entry does not conform to the
      nociceptor_sodium_channel_excitability module.
  downstream:
  - target: Vestibular Allodynia
    description: >-
      A sensitized, TRPV1-enriched nociceptor population in the vestibular
      epithelium is the proximate cause of pain on ordinarily innocuous contact.
    causal_link_type: DIRECT
  - target: Vulvar Burning Pain
    description: >-
      TRPV1 is triggered by noxious heat, protons and inflammatory mediators as
      well as by mechanical context, so a TRPV1-enriched nociceptor population is
      the proposed origin of the burning quality of the pain, including the
      component present outside contact. Recorded as indirect because the source
      offers it as a hypothesis rather than a measured link.
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    evidence:
    - reference: PMID:14987622
      reference_title: "Increased vanilloid receptor VR1 innervation in vulvodynia."
      supports: SUPPORT
      directness: INDIRECT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        We hypothesize that increased expression of VR1 by nociceptors could mediate some of the symptoms in vulvodynia, for which systemic or topical specific VR1 antagonists may provide novel treatment.
      explanation: >-
        The authors' own proposal that the receptor change mediates the symptoms;
        graded INDIRECT because it is labelled a hypothesis in the source.
  - target: Central Pain Amplification
    description: >-
      Sustained peripheral nociceptive input from the vestibule is the
      conventional route to the generalized pressure pain hypersensitivity
      measured outside the pelvis, though the direction of causation has not been
      established in this disorder.
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
- name: Vestibular Allodynia
  biological_scale: TISSUE
  description: >-
    Pain on light touch confined to the vulvar vestibule, elicited clinically by
    the cotton-swab test and quantified experimentally by lowered vulvar pressure
    pain thresholds. This is the cardinal objective sign of the localized form
    and is the node every treatment in this entry is ultimately aimed at.
  evidence:
  - reference: PMID:15229011
    reference_title: "Quantitative sensory testing in vulvodynia patients and increased peripheral pressure pain sensitivity."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Pain thresholds at all vulvar locations were lower in the women with vulvodynia than in pain-free control subjects.
    explanation: >-
      Instrumented confirmation of vulvar allodynia against pain-free controls,
      independent of the subjective swab test.
  downstream:
  - target: Provoked Vestibular Pain
    description: >-
      The allodynia measured by quantitative sensory testing is the same
      phenomenon the patient reports as contact-provoked vestibular pain and the
      examiner elicits with the cotton swab; this edge connects the measured sign
      to the presenting symptom.
    causal_link_type: DIRECT
  - target: Dyspareunia
    description: >-
      Vestibular contact during vaginal penetration is the commonest provoking
      stimulus, which is why the presenting complaint is usually pain with
      intercourse rather than pain at rest.
    causal_link_type: DIRECT
  - target: Pelvic Floor Muscle Hypertonicity
    description: >-
      Repeated painful penetration attempts elicit protective guarding of the
      pelvic floor, which becomes sustained.
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - anticipatory and reflex protective muscle guarding
- name: Pelvic Floor Muscle Hypertonicity
  biological_scale: TISSUE
  description: >-
    Women with provoked vestibulodynia show a smaller levator hiatus area, a
    smaller anorectal angle and a larger levator plate angle at rest, together
    indicating raised resting pelvic floor muscle tone, and they generate smaller
    changes on maximal contraction, indicating reduced strength and control. The
    measurement was made by transperineal ultrasound without vaginal insertion,
    which matters: earlier work using intravaginal instruments could not separate
    genuine hypertonicity from a reaction to the painful measurement itself.
  locations:
  - preferred_term: levator ani muscle
    term:
      id: UBERON:0001326
      label: levator ani muscle
  evidence:
  - reference: PMID:24344835
    reference_title: "Morphometry of the pelvic floor muscles in women with and without provoked vestibulodynia using 4D ultrasound."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Women with PVD showed a significantly smaller levator hiatus area, a smaller anorectal angle, and a larger levator plate angle at rest compared with asymptomatic women, suggesting an increase in PFM tone.
    explanation: >-
      Direct morphometric evidence of raised resting tone in a nulliparous
      case-control sample, obtained by a pain-free method.
  - reference: PMID:24344835
    reference_title: "Morphometry of the pelvic floor muscles in women with and without provoked vestibulodynia using 4D ultrasound."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      During PFM maximal contraction, smaller changes in levator hiatus area narrowing, displacement of the bladder neck, and changes of the anorectal and of the levator plate angles were found in women with PVD compared with controls, which may indicate poorer PFM strength and control.
    explanation: >-
      Adds the contractile deficit, which is the specific target of pelvic floor
      physical therapy in this entry.
  downstream:
  - target: Dyspareunia
    description: >-
      Raised resting tone and impaired voluntary relaxation narrow the introitus
      and add a muscular component to penetration pain that is separable from the
      mucosal one.
    causal_link_type: DIRECT
- name: Central Pain Amplification
  biological_scale: ORGANISM
  mechanism_confidence: PROVISIONAL
  description: >-
    Pressure pain thresholds are lowered not only at the vulva but at the thumb,
    deltoid and shin, and equally so in localized and generalized presentations.
    That distribution cannot be explained by vestibular pathology and points to
    altered central pain processing. It is recorded as PROVISIONAL because the
    observation is cross-sectional: whether central amplification follows
    sustained vestibular input, precedes it as a predisposition, or both, is not
    established.
  biological_processes:
  - preferred_term: sensory perception of pain
    modifier: INCREASED
    term:
      id: GO:0019233
      label: sensory perception of pain
  evidence:
  - reference: PMID:15229011
    reference_title: "Quantitative sensory testing in vulvodynia patients and increased peripheral pressure pain sensitivity."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Women with vulvodynia displayed significantly increased pressure pain sensitivity in both the vulvar region and in peripheral body regions, suggesting a "central" component to the mechanisms mediating this disorder.
    explanation: >-
      The extra-pelvic distribution of the sensitivity is the observation this
      node rests on.
  - reference: PMID:24807511
    reference_title: "Gynecological disorders in bladder pain syndrome/interstitial cystitis patients."
    supports: SUPPORT
    directness: INDIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Women with vestibulodynia are likely to have other additional pain conditions, such as fibromyalgia, irritable bowel syndrome or chronic fatigue syndrome.
    explanation: >-
      Clustering with other chronic overlapping pain conditions is consistent
      with a shared central mechanism; graded INDIRECT because comorbidity does
      not by itself demonstrate altered central processing.
  downstream:
  - target: Widespread Pressure Pain Hypersensitivity
    description: >-
      The generalized lowering of pressure pain thresholds is the measurable
      expression of this node outside the pelvis.
    causal_link_type: DIRECT
  - target: Anxiety
    description: >-
      Drawn from the central node rather than from the vestibular ones because
      the disease-specific review names anxiety alongside central pain mechanisms
      as part of one interplay, and because this is the node the entry's
      cognitive behavioural therapy record targets. The source describes onset
      and maintenance together, so it does not fix the direction; the edge
      records the direction the pathograph can carry and says the intermediates
      are unknown. See the psychological_factor_direction discussion.
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
  - target: Depression
    description: >-
      Same reasoning as the anxiety edge, resting on the same sentence naming
      depression among the factors involved in onset and maintenance.
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
- name: Androgen Receptor Signalling Insufficiency
  biological_scale: MOLECULAR
  mechanism_confidence: HYPOTHETICAL
  description: >-
    In women who developed vestibulodynia while taking combined hormonal
    contraceptives, androgen receptor CAG repeat lengths were longer than in
    women taking the same contraceptives without developing pain, and calculated
    free testosterone was higher rather than lower in the affected group. The
    proposed mechanism - a less efficient receptor combined with contraceptive
    suppression of free androgen leaving vestibular tissue androgen-deprived - is
    the authors' speculation, and the free testosterone result does not run in
    the direction that hypothesis predicts. Recorded as HYPOTHETICAL on a sample
    of 30 cases and 17 controls.
  genes:
  - preferred_term: AR
    term:
      id: hgnc:644
      label: AR
  evidence:
  - reference: PMID:25187224
    reference_title: "Polymorphisms of the androgen receptor gene and hormonal contraceptive induced provoked vestibulodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The mean number of CAG repeats in the study group was significantly greater than the control group (22.05 ± 2.98 vs. 20.61 ± 2.19, respectively; P = 0.025).
    explanation: >-
      The genotype difference between contraceptive-exposed women who did and did
      not develop vestibulodynia is the finding this node rests on.
  - reference: PMID:25187224
    reference_title: "Polymorphisms of the androgen receptor gene and hormonal contraceptive induced provoked vestibulodynia."
    supports: REFUTE
    directness: INDIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Among those who were taking drospirenone-containing CHCs, the mean calculated free testosterone was 0.189 ± 0.115 ng/dL in the study group and 0.127 ± 0.054 ng/dL in the control group, all of whom were taking drospirenone-containing CHCs (P = 0.042).
    explanation: >-
      Free testosterone was higher in cases, which is the opposite of what an
      androgen-deprivation mechanism predicts; recorded against this node rather
      than omitted.
  downstream:
  - target: Nociceptor Sensitization in the Vestibular Epithelium
    description: >-
      Androgen-dependent maintenance of the vestibular mucosa is the proposed
      route by which contraceptive exposure lowers the nociceptive threshold, on
      this hypothesis.
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    hypothesis_groups:
    - hormonal_vestibulodynia
mechanistic_hypotheses:
- hypothesis_group_id: hormonal_vestibulodynia
  hypothesis_label: Androgen-deprivation route to contraceptive-associated vestibulodynia
  status: EMERGING
  description: >-
    That combined hormonal contraceptives precipitate vestibulodynia in women
    whose androgen receptor is already less efficient, by depriving the
    vestibular mucosa of androgen support. The genotype association has been
    observed in one small cohort; the accompanying hormone measurement ran in the
    wrong direction for the hypothesis, and no interventional or longitudinal
    test exists.
  evidence:
  - reference: PMID:25187224
    reference_title: "Polymorphisms of the androgen receptor gene and hormonal contraceptive induced provoked vestibulodynia."
    supports: SUPPORT
    directness: INDIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      We speculate that the risk of developing CHC-induced vestibulodynia may be due to lowered free testosterone combined with an inefficient AR that predisposes women to vestibular pain.
    explanation: >-
      This is the authors' own statement of the hypothesis, and is labelled as
      speculation in the source; graded INDIRECT for that reason.
phenotypes:
- category: Genitourinary
  name: Provoked Vestibular Pain
  description: >-
    Pain localized to the vulvar vestibule and elicited by contact - intercourse,
    tampon insertion, or the cotton-swab test - with the remainder of the vulva
    non-tender. This is the defining presentation of the localized provoked form.
  phenotype_term:
    preferred_term: vulvodynia
    term:
      id: HP:0030943
      label: Vulvodynia
    temporality: CHRONIC
  diagnostic: true
  evidence:
  - reference: PMID:32355269
    reference_title: "Vulvodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Diagnosis is established through careful medical history and pelvic examination, including the cotton-swab test.
    explanation: >-
      Names the examination manoeuvre that elicits and localizes this phenotype.
- category: Genitourinary
  name: Vulvar Burning Pain
  description: >-
    Burning or knife-like vulvar pain, which may be present outside sexual
    contact (unprovoked) as well as on contact. It is the symptom used to
    identify the condition in population screening.
  phenotype_term:
    preferred_term: vulvodynia
    term:
      id: HP:0030943
      label: Vulvodynia
    temporality: CHRONIC
  evidence:
  - reference: PMID:21963307
    reference_title: "Prevalence and demographic characteristics of vulvodynia in a population-based sample."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Vulvodynia is a chronic pain condition associated with local hypersensitivity of the vulva that may be provoked (e.g., intercourse or tampon use), unprovoked (spontaneous), or both.
    explanation: >-
      Establishes that the pain occurs in provoked, unprovoked and mixed forms,
      which is why this phenotype is recorded separately from the provoked one.
- category: Genitourinary
  name: Dyspareunia
  description: >-
    Pain with vaginal penetration, the usual presenting complaint. Localized
    provoked vulvodynia is the commonest cause of premenopausal chronic
    intercourse pain.
  phenotype_term:
    preferred_term: Dyspareunia
    term:
      id: HP:0030016
      label: Dyspareunia
    temporality: CHRONIC
  evidence:
  - reference: PMID:25679469
    reference_title: "Site-specific mesenchymal control of inflammatory pain to yeast challenge in vulvodynia-afflicted and pain-free women."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The most common cause of premenopausal, chronic intercourse pain (dyspareunia) is localized provoked vulvodynia (LPV)
    explanation: >-
      States the relationship between this disorder and dyspareunia in the
      premenopausal population.
- category: Neurologic
  name: Widespread Pressure Pain Hypersensitivity
  description: >-
    Lowered pressure pain thresholds at body sites remote from the pelvis -
    thumb, deltoid and shin - present in both localized and generalized
    presentations.
  phenotype_term:
    preferred_term: Allodynia
    term:
      id: HP:0012533
      label: Allodynia
  evidence:
  - reference: PMID:15229011
    reference_title: "Quantitative sensory testing in vulvodynia patients and increased peripheral pressure pain sensitivity."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Similarly, peripheral pain thresholds were lower at the thumb in women with vulvodynia when obtained by discrete ascending or random staircase paradigms, as well as at the thumb, deltoid, and shin when tested by dolorimeter (P <.05).
    explanation: >-
      Gives the remote body sites and the testing paradigms behind this
      phenotype.
- category: Psychiatric
  name: Anxiety
  description: >-
    Anxiety is one of the factors named in disease-specific reviews as
    participating in the onset and maintenance of vulvodynia, alongside
    depression and interpersonal factors.
  phenotype_term:
    preferred_term: Anxiety
    term:
      id: HP:0000739
      label: Anxiety
  evidence:
  - reference: PMID:32355269
    reference_title: "Vulvodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The onset and maintenance of vulvodynia involves a complex interplay of peripheral and central pain mechanisms, pelvic floor muscle and autonomic dysfunction, anxiety, depression and childhood maltreatment as well as cognitive-affective, behavioural and interpersonal factors.
    explanation: >-
      Names anxiety among the factors involved in onset and maintenance.
- category: Psychiatric
  name: Depression
  description: >-
    Depression accompanies vulvodynia and is named among the factors involved in
    its onset and maintenance; the direction of the relationship is not resolved.
  phenotype_term:
    preferred_term: Depression
    term:
      id: HP:0000716
      label: Depression
  evidence:
  - reference: PMID:32355269
    reference_title: "Vulvodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The onset and maintenance of vulvodynia involves a complex interplay of peripheral and central pain mechanisms, pelvic floor muscle and autonomic dysfunction, anxiety, depression and childhood maltreatment as well as cognitive-affective, behavioural and interpersonal factors.
    explanation: >-
      Names depression among the factors involved in onset and maintenance.
genetic:
- name: IL1RN
  gene_term:
    preferred_term: IL1RN
    term:
      id: hgnc:6000
      label: IL1RN
  relationship_type: SUSCEPTIBILITY
  notes: >-
    Homozygosity for allele 2 of the interleukin 1 receptor antagonist gene was
    markedly over-represented in women with vulvar vestibulitis compared with
    controls. The interleukin 1 receptor antagonist down-regulates
    proinflammatory IL-1 signalling, so a less effective allele is
    mechanistically coherent with the exaggerated local inflammatory response
    recorded above. The association comes from one case-control study of 68 cases
    and has not been replicated at genome-wide scale here.
  evidence:
  - reference: PMID:10694325
    reference_title: "Interleukin 1 receptor antagonist gene polymorphism in women with vulvar vestibulitis."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Allele 2 of the gene encoding the interleukin 1 receptor antagonist was present in homozygous form in 52.9% of women with vulvar vestibulitis. In marked contrast only 8. 5% of the control women and 2.5% of women with human papillomavirus were homozygous for this allele (P </=.0001).
    explanation: >-
      Gives the genotype frequencies in cases and both control groups that the
      susceptibility claim rests on.
- name: AR
  gene_term:
    preferred_term: AR
    term:
      id: hgnc:644
      label: AR
  relationship_type: SUSCEPTIBILITY
  notes: >-
    Longer androgen receptor CAG repeat tracts were found in women who developed
    vestibulodynia while taking combined hormonal contraceptives than in
    contraceptive-exposed women who did not. This is a gene-by-exposure
    susceptibility claim rather than a disease gene, and rests on 30 cases and 17
    controls; see the hormonal_vestibulodynia hypothesis for what it does and
    does not establish.
  evidence:
  - reference: PMID:25187224
    reference_title: "Polymorphisms of the androgen receptor gene and hormonal contraceptive induced provoked vestibulodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In the study cohort, women who developed vestibulodynia while taking CHCs are more likely to have longer CAG repeats in the AR than women who took the same type of CHC but did not develop vestibulodynia.
    explanation: >-
      States the gene-by-exposure association, including the exposure-matched
      comparison group that makes it a susceptibility rather than a main effect.
environmental:
- name: Combined hormonal contraceptive use
  description: >-
    Use of combined hormonal contraceptives preceding the onset of vestibular
    pain. The exposure is recorded here because it defines the cohort in which
    the androgen receptor association was found; it is a predisposing context on
    a specific genetic background rather than a demonstrated cause of vulvodynia
    in general.
  exposure_term:
    preferred_term: exposure to combined hormonal contraceptive
  evidence:
  - reference: PMID:25187224
    reference_title: "Polymorphisms of the androgen receptor gene and hormonal contraceptive induced provoked vestibulodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Women who developed vestibulodynia (vulvar vestibulitis) while taking combined hormonal contraceptives (CHCs) and a control group of women were tested for polymorphisms of the gene coding for the androgen receptor (AR) that is located on the X chromosome.
    explanation: >-
      Establishes the exposure-defined case group this environmental record
      describes.
  influences_mechanisms:
  - target: Androgen Receptor Signalling Insufficiency
    environmental_effect: PREDISPOSES
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Contraceptive suppression of circulating free androgen is the exposure arm
      of the proposed gene-by-environment mechanism at this node.
    evidence:
    - reference: PMID:25187224
      reference_title: "Polymorphisms of the androgen receptor gene and hormonal contraceptive induced provoked vestibulodynia."
      supports: SUPPORT
      directness: INDIRECT
      evidence_source: HUMAN_CLINICAL
      snippet: >-
        We speculate that the risk of developing CHC-induced vestibulodynia may be due to lowered free testosterone combined with an inefficient AR that predisposes women to vestibular pain.
      explanation: >-
        The authors' statement of how the exposure is proposed to act on androgen
        receptor signalling; graded INDIRECT because it is labelled speculation
        in the source.
  notes: >-
    ECTO was searched for a contraceptive-exposure term and none was found, so
    exposure_term carries a free-text preferred_term with no binding rather than
    a stretched match.
treatments:
- name: Pelvic Floor Physical Therapy
  description: >-
    Multimodal pelvic floor muscle physical therapy - biofeedback, manual
    therapy, dilators, electrical stimulation and education - aimed at the raised
    resting tone and impaired contractile control documented above. It is a
    first-line recommendation in clinical guidelines, but the supporting
    literature is dominated by uncontrolled designs.
  therapeutic_modality: BEHAVIORAL
  treatment_term:
    preferred_term: pelvic floor muscle physical therapy
    term:
      id: NCIT:C15302
      label: Physical Therapy
  target_mechanisms:
  - target: Pelvic Floor Muscle Hypertonicity
    description: >-
      The modality acts on the muscular node directly, by retraining resting tone
      and voluntary relaxation.
  evidence:
  - reference: PMID:28363763
    reference_title: "Systematic Review of the Effectiveness of Physical Therapy Modalities in Women With Provoked Vestibulodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The vast majority of studies showed that physical therapy modalities such as biofeedback, dilators, electrical stimulation, education, multimodal physical therapy, and multidisciplinary approaches were effective for decreasing pain during intercourse and improving sexual function.
    explanation: >-
      Systematic review finding of benefit across 43 studies, which is the basis
      for first-line use.
  - reference: PMID:28363763
    reference_title: "Systematic Review of the Effectiveness of Physical Therapy Modalities in Women With Provoked Vestibulodynia."
    supports: SUPPORT
    directness: INDIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Most studies had a high risk of bias mainly associated with the lack of a comparison group.
    explanation: >-
      Recorded alongside the benefit claim because it is the same review's
      assessment of how much weight that claim can carry; graded INDIRECT because
      it bears on the strength of the recommendation rather than asserting it.
- name: Cognitive Behavioural Therapy
  description: >-
    Pain-focused cognitive behavioural therapy, recommended in a stepwise
    approach alongside pelvic floor physical therapy. It targets the
    cognitive-affective and behavioural factors named in disease-specific reviews
    as maintaining the pain, and the central amplification node.
  therapeutic_modality: BEHAVIORAL
  treatment_term:
    preferred_term: cognitive behavioural therapy
    term:
      id: NCIT:C64345
      label: Cognitive Behavior Therapy
  target_mechanisms:
  - target: Central Pain Amplification
    description: >-
      The intervention addresses the cognitive-affective and behavioural
      contribution to pain maintenance rather than the vestibular mucosa.
  evidence:
  - reference: PMID:32355269
    reference_title: "Vulvodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Given the absence of empirically supported treatment guidelines, a stepwise approach of pelvic floor physical therapy and cognitive behavioural therapy as well as medical management is suggested, with surgery as the last option.
    explanation: >-
      States the recommended position of this modality, and in the same sentence
      that the guideline base is not empirically supported.
- name: Topical Lidocaine
  description: >-
    Topical 5% lidocaine applied to the vestibule, intended to block the
    sensitized mucocutaneous nerve endings directly. Widely used empirically; it
    did not outperform placebo cream in the one adequately powered randomized
    trial, and a subsequent network meta-analysis found no dyspareunia benefit.
  therapeutic_modality: SMALL_MOLECULE
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: lidocaine
      term:
        id: CHEBI:6456
        label: lidocaine
  target_mechanisms:
  - target: Nociceptor Sensitization in the Vestibular Epithelium
    description: >-
      Sodium channel blockade at mucocutaneous nerve endings is the intended
      peripheral action, whatever its measured efficacy.
  evidence:
  - reference: PMID:20733439
    reference_title: "Oral desipramine and topical lidocaine for vulvodynia: a randomized controlled trial."
    supports: REFUTE
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Oral desipramine and topical lidocaine, as monotherapy or in combination, failed to reduce vulvodynia pain more than placebo.
    explanation: >-
      The trial's primary conclusion refutes efficacy for pain reduction over
      placebo.
  - reference: PMID:31364893
    reference_title: "Systematic review and meta-analysis of the effects of treatment modalities for vestibulodynia in women."
    supports: REFUTE
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In traditional MA, interventions did not reduce dyspareunia (MD = 0.08; 95%CI = -0.49 to 0.64), DVS (MD = -0.04; 95%CI = -0.31 to 0.24; 4 interventions), or MPQ (MD = -0.17; 95%CI = -2.16 to 1.81; 4 interventions).
    explanation: >-
      Pooled result across the randomized evidence, including topical lidocaine,
      showing no dyspareunia benefit.
  notes: >-
    Retained in the entry despite the negative result because it remains in
    widespread empiric use and the negative trial is itself a substantive finding
    about this disorder.
- name: Oral Desipramine
  description: >-
    A secondary-amine tricyclic antidepressant given orally for its central
    antinociceptive action at the spinal dorsal horn. It failed to reduce pain
    more than placebo in the randomized trial, but improved sexual satisfaction -
    the one secondary endpoint of thirteen that separated from placebo, and a
    result the later network meta-analysis reproduced.
  therapeutic_modality: SMALL_MOLECULE
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: desipramine
      term:
        id: CHEBI:47781
        label: desipramine
  target_mechanisms:
  - target: Central Pain Amplification
    description: >-
      Tricyclic antidepressants are given here for their action on central pain
      modulation rather than on the vestibular mucosa.
  evidence:
  - reference: PMID:20733439
    reference_title: "Oral desipramine and topical lidocaine for vulvodynia: a randomized controlled trial."
    supports: REFUTE
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Compared with placebo, we found no significant difference in tampon-test pain reduction with desipramine (t=0.90; P=.37) or lidocaine (t=1.27; P=.21).
    explanation: >-
      The primary-endpoint comparison refutes a pain-reduction effect for
      desipramine.
  - reference: PMID:20733439
    reference_title: "Oral desipramine and topical lidocaine for vulvodynia: a randomized controlled trial."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Of the remaining 12 outcome measures, only the Index of Sexual Satisfaction, improved with desipramine compared with placebo (t=-2.81; P=.006).
    explanation: >-
      A separate sentence reporting the one secondary endpoint that did favour
      desipramine; recorded as its own item because it supports a different claim
      from the refuting one above.
  - reference: PMID:31364893
    reference_title: "Systematic review and meta-analysis of the effects of treatment modalities for vestibulodynia in women."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In NMA, oral desipramine with or without lidocaine significantly improved ISS vs. other treatments.
    explanation: >-
      Independent pooled confirmation of the sexual-satisfaction benefit, which
      is the only outcome this drug has support for.
- name: Electromyography-Guided Botulinum Toxin A Injection
  description: >-
    Onabotulinum toxin A injected into the superficial perineal muscles under
    electromyographic guidance, aimed at the pelvic floor hypertonicity arm
    rather than at the vestibular mucosa. It is the one intervention in this
    entry with a positive placebo-controlled randomized result: pain, quality of
    life and sexual function all separated from saline at three months in a
    60-patient trial. The trialists read that as evidence that muscular
    dysfunction is itself a driver of the pain rather than only a reaction to it,
    which is a claim about the pathograph and not only about the drug.
  therapeutic_modality: OTHER
  treatment_term:
    preferred_term: electromyography-guided botulinum toxin type A injection
    term:
      id: NCIT:C157775
      label: Botulinum Toxin Therapy
    therapeutic_agent:
    - preferred_term: onabotulinum toxin A
      term:
        id: CHEBI:3160
        label: Botulinum toxin type A
  target_mechanisms:
  - target: Pelvic Floor Muscle Hypertonicity
    description: >-
      Chemodenervation of the superficial perineal muscles acts on the raised
      resting tone documented at this node; the electromyographic guidance is
      what selects the muscles to inject.
  evidence:
  - reference: PMID:41419152
    reference_title: "Electromyography-guided botulinum toxin injections in provoked vestibulodynia: a randomized double-blind placebo-controlled clinical trial."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      After 3 months, the pain visual analog scale decreased in the treated group to 5.04±0.61 vs 7.37±0.45 in the placebo group (P=.008).
    explanation: >-
      The primary-endpoint result against saline placebo, which is what
      distinguishes this treatment from the three drug records above.
  - reference: PMID:41419152
    reference_title: "Electromyography-guided botulinum toxin injections in provoked vestibulodynia: a randomized double-blind placebo-controlled clinical trial."
    supports: SUPPORT
    directness: INDIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      We suggest that muscular dysfunction is a key element of vestibulodynia pain.
    explanation: >-
      The trialists' mechanistic reading of their own result, cited here as
      therapeutic validation of the pelvic floor node; graded INDIRECT because
      the inference from treatment response to mechanism is an extra step.
  notes: >-
    Recorded against the muscular node rather than the mucosal one on purpose.
    The trial postdates the pooled analysis cited on the drug records above, so
    this single 60-patient study carries the claim on its own and is not yet
    covered by any synthesis in this entry.
- name: Oral Gabapentin
  description: >-
    Extended-release gabapentin given orally for the neuropathic features of the
    disorder. It is commonly prescribed and appears in several vulvodynia
    treatment guidelines, but until 2018 no placebo-controlled randomized trial
    of it existed; when one was run it separated from placebo on none of the
    three pain outcomes, and its authors concluded against recommending
    gabapentin alone.
  therapeutic_modality: SMALL_MOLECULE
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: gabapentin
      term:
        id: CHEBI:42797
        label: gabapentin
  target_mechanisms:
  - target: Central Pain Amplification
    description: >-
      Gabapentin is given here on the reasoning that vulvodynia behaves like a
      neuropathic pain state, so the intended action is on central pain
      processing rather than on the vestibular mucosa.
  evidence:
  - reference: PMID:29742655
    reference_title: "Gabapentin for the Treatment of Vulvodynia: A Randomized Controlled Trial."
    supports: SUPPORT
    directness: INDIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Women with vulvodynia often present with certain neuropathic characteristics, such as dynamic allodynia (pain in response to light touch).
    explanation: >-
      States the rationale for using a neuropathic pain drug in this disorder,
      which is what this treatment record's mechanism target rests on; graded
      INDIRECT because it motivates the choice rather than demonstrating
      efficacy.
  - reference: PMID:29742655
    reference_title: "Gabapentin for the Treatment of Vulvodynia: A Randomized Controlled Trial."
    supports: REFUTE
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In this cohort, extended-release gabapentin, as compared with a placebo, did not reduce tampon test pain. These data do not support the recommendation of gabapentin alone as treatment for vulvodynia.
    explanation: >-
      The trial's own conclusion refutes efficacy on the primary endpoint and
      refuses the guideline recommendation.
  notes: >-
    Retained for the same reason as topical lidocaine and oral desipramine: the
    drug remains in common use and the negative trial is itself a substantive
    finding about this disorder. The trial is a crossover design in 89 women
    powered for a 1-point tampon-test difference, and is registered as
    NCT01301001.
- name: Vestibulectomy
  description: >-
    Surgical excision of the painful vestibular mucosa, reserved for refractory
    localized provoked disease. It is the intervention with the largest reported
    effect, and it removes precisely the tissue in which the neuroproliferation
    and receptor changes above are found - the surgical specimens are in fact the
    source of most of that histological evidence. Long-term follow-up series are
    uncontrolled and subject to responder bias.
  therapeutic_modality: SURGERY
  treatment_term:
    preferred_term: vestibulectomy
    term:
      id: NCIT:C15329
      label: Surgical Procedure
  target_mechanisms:
  - target: Vestibular Mucosal Neuroproliferation
    description: >-
      Excision removes the hyperinnervated vestibular mucosa itself, which is why
      the procedure is mechanistically coherent with the pathograph even where
      the trial evidence is weak.
  evidence:
  - reference: PMID:32569021
    reference_title: "Evaluation of Long-Term Surgical Success and Satisfaction of Patients After Vestibulectomy."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Penetration pain averaged 9.13 (scale = 0-10) before surgery and dropped to 0.47 at the time of follow up (p < .001).
    explanation: >-
      Quantifies the pain reduction at 12-24 year follow-up in the reported
      series.
  - reference: PMID:20733439
    reference_title: "Oral desipramine and topical lidocaine for vulvodynia: a randomized controlled trial."
    supports: SUPPORT
    directness: INDIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      During the open-label phase, women undergoing vestibulectomy surgery reported significantly improved pain as measured by cotton swab test and the McGill Pain Scale compared with nonsurgical alternatives.
    explanation: >-
      Supports surgical benefit from within the randomized trial's own cohort;
      graded INDIRECT because the comparison is open-label and non-randomized.
  notes: >-
    The long-term series reports 32 of 85 eligible patients (38%) participating,
    so the satisfaction figures describe respondents rather than the operated
    cohort.
differential_diagnoses:
- name: Vulvovaginal candidiasis
  description: >-
    Active yeast infection produces vulvar burning and dyspareunia and must be
    excluded before the diagnosis is made; culture- or smear-proven Candida was
    an exclusion criterion in the randomized trial of this disorder.
  distinguishing_features:
  - positive culture or microscopy for Candida species
  - response to antifungal treatment
- name: Lichen sclerosus and other vulvar dermatoses
  description: >-
    Vulvar dermatoses cause chronic soreness with visible skin change; vulvodynia
    by definition has no such identifiable lesion.
  distinguishing_features:
  - visible atrophic or sclerotic skin change on examination
  - diagnostic histopathology
- name: Pudendal neuralgia
  description: >-
    A named neuropathy of the pudendal nerve, distinguished by a nerve-territory
    distribution extending beyond the vestibule.
  distinguishing_features:
  - pain in the full pudendal nerve distribution rather than confined to the vestibule
discussions:
- discussion_id: mast_cell_contribution
  kind: CONTROVERSY
  status: OPEN
  prompt: >-
    Do mast cells contribute to vestibular pain in vulvodynia, or is the reported
    mast cell excess an artefact of case selection and unmatched controls?
  attaches_to:
  - pathophysiology#Vestibular Mucosal Immune Activation
  rationale: >-
    A 35-specimen series reports mast cell densities several-fold above control
    tissue and interprets them as a secondary hyperplasia reflecting an activated
    immune system. A larger case-control study of 100 confirmed cases with
    racially matched controls, using blinded c-KIT counting, finds no difference
    at all - and additionally shows mast cell density varies by race in controls,
    which is a plausible confounder for the earlier positive reports. Both are
    recorded on the node. Resolving this matters practically, because mast
    cell-directed therapy is proposed on the strength of the positive finding.
- discussion_id: negative_trial_base
  kind: KNOWLEDGE_GAP
  status: OPEN
  prompt: >-
    Why do the drug treatments most often prescribed for vulvodynia fail against
    placebo when the peripheral mechanism they target is well documented?
  attaches_to:
  - treatments#Topical Lidocaine
  - treatments#Oral Desipramine
  - treatments#Oral Gabapentin
  - pathophysiology#Nociceptor Sensitization in the Vestibular Epithelium
  rationale: >-
    Every arm of the desipramine and lidocaine trial, including double placebo,
    reported substantial pain reduction, and the trial's own conclusion
    attributes the improvement to placebo or placebo-independent effects. The
    separate gabapentin crossover trial then returned the same answer for a third
    drug, on the same tampon-test endpoint. That is compatible with the drugs
    being ineffective, with the tampon test being insensitive to the change they
    produce, or with the disorder having a strong natural-history component over
    the trial period. The pooled analysis of four randomized trials covers only
    five interventions in 275 women in total, so the evidence base cannot
    currently distinguish these. That the same endpoint carries all three
    negative results is itself part of the question. The contrast with the one
    positive placebo-controlled result in this entry is suggestive rather than
    decisive: botulinum toxin acts on the pelvic floor node, not on the mucosal
    nociceptor node all three drugs are aimed at, which would be consistent with
    the peripheral mucosal target being the wrong one to drug - but it is a
    single trial on a different endpoint.
  evidence:
  - reference: PMID:20733439
    reference_title: "Oral desipramine and topical lidocaine for vulvodynia: a randomized controlled trial."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Placebo or placebo-independent effects are behind the substantial pain improvement seen in all treatment allocations.
    explanation: >-
      The trialists' own account of what produced the improvement, which is the
      observation this gap is about.
- discussion_id: central_versus_peripheral_order
  kind: OPEN_QUESTION
  status: OPEN
  prompt: >-
    Does central pain amplification in vulvodynia follow sustained vestibular
    nociceptive input, or does it precede and predispose to it?
  attaches_to:
  - pathophysiology#Central Pain Amplification
  - pathophysiology#Nociceptor Sensitization in the Vestibular Epithelium
  rationale: >-
    The generalized pressure pain hypersensitivity was measured cross-sectionally
    and was equally present in localized and generalized presentations, which is
    hard to reconcile with it being purely a consequence of vestibular input. The
    edge drawn from the nociceptor node to the central node in this entry is
    therefore recorded as INDIRECT_UNKNOWN_INTERMEDIATES and the central node as
    PROVISIONAL. A prospective cohort measuring remote pain thresholds before
    onset would settle it.
- discussion_id: psychological_factor_direction
  kind: OPEN_QUESTION
  status: OPEN
  prompt: >-
    Are anxiety and depression in vulvodynia consequences of the pain, factors
    that predispose to and maintain it, or both?
  attaches_to:
  - phenotypes#Anxiety
  - phenotypes#Depression
  - pathophysiology#Central Pain Amplification
  rationale: >-
    The only source this entry has for the association names anxiety and
    depression among the factors involved in onset and maintenance, in one list
    with central pain mechanisms and cognitive-affective factors. That sentence
    asserts an interplay and deliberately does not separate cause from
    consequence, so an edge in either direction over-reads it. The pathograph
    draws them as consequences of the central amplification node, which follows
    this knowledge base's convention for psychiatric phenotypes and matches the
    node the cognitive behavioural therapy record targets, but that choice is a
    modelling decision and not a finding. Settling it needs a longitudinal cohort
    with psychiatric measures before onset; the same design would settle the
    central_versus_peripheral_order question.
  evidence:
  - reference: PMID:32355269
    reference_title: "Vulvodynia."
    supports: SUPPORT
    directness: INDIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Future efforts should aim to increase girls', women's and healthcare professionals' education and awareness of vulvodynia, phenotype different subgroups of women based on biopsychosocial characteristics among more diverse samples, conduct longitudinal studies and improve clinical trial designs.
    explanation: >-
      The review's own call for longitudinal studies, which is the design this
      question needs; graded INDIRECT because it states the gap in research
      design rather than the direction of the association.
diagnosis:
- name: Cotton-swab test
  description: >-
    Light pressure applied with a cotton swab at defined points of the vestibule,
    with the labia and lower vagina tested as internal negative controls. It
    localizes the allodynia and is the manoeuvre on which the localized provoked
    diagnosis rests.
  evidence:
  - reference: PMID:32355269
    reference_title: "Vulvodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Diagnosis is established through careful medical history and pelvic examination, including the cotton-swab test.
    explanation: >-
      Names the test as part of establishing the diagnosis.
- name: Exclusion of identifiable vulvar disease
  description: >-
    Vulvodynia is defined by the absence of a specific identifiable cause, so the
    diagnosis requires that infection, dermatosis and neurological disease have
    been looked for and not found. The 2015 tri-society terminology formalized
    this by separating vulvar pain caused by a specific disorder from vulvodynia.
  evidence:
  - reference: PMID:27045260
    reference_title: "2015 ISSVD, ISSWSH, and IPPS Consensus Terminology and Classification of Persistent Vulvar Pain and Vulvodynia."
    supports: SUPPORT
    directness: DIRECT
    evidence_source: OTHER
    snippet: >-
      In 2015, the ISSVD, ISSWSH, and IPPS adopted a new vulvar pain and vulvodynia terminology that acknowledges the complexity of the clinical presentation and pathophysiology involved in vulvar pain and vulvodynia, and incorporates new information derived from evidence-based studies conducted since the last terminology published in 2003.
    explanation: >-
      Documents the consensus terminology that governs how this diagnosis is
      framed; graded OTHER because it reports an expert-consensus process rather
      than a study.
notes: >-
  Scope. This entry curates vulvodynia as the tri-society terminology defines it
  - persistent vulvar pain with no identifiable specific cause - and models the
  localized provoked (vestibulodynia) form in most detail, because that is where
  nearly all of the mechanistic evidence has been generated. Generalized and
  unprovoked presentations share the phenotype records and the central
  amplification node but have little mechanism-specific evidence of their own.

  Module conformance. No conforms_to is declared. The obvious candidate,
  nociceptor_sodium_channel_excitability, is explicitly scoped to Mendelian
  variants in SCN9A/SCN10A/SCN11A and to channel-intrinsic excitability, and the
  one study here that looked for a sodium channel signature found Nav1.8 fibres
  scarce in cases and controls alike. Conforming would assert a mechanism the
  evidence does not support.

  Ontology gaps found while curating, in the same spirit as the gaps recorded on
  issue #7837. UBERON has no vulvar vestibule term, so the vestibule-specific
  nodes are located to UBERON:0000997 mammalian vulva, which is broader than the
  claim. ECTO has no combined hormonal contraceptive exposure term, so that
  environmental record carries an unbound preferred_term. HP has a single
  Vulvodynia term (HP:0030943) with no provoked/unprovoked or
  localized/generalized distinction, so the two vulvar pain phenotypes here bind
  the same HP term and are separated by name and description only.

  Co-occurring conditions. The chronic overlapping pain conditions that
  accompany vulvodynia are recorded under epidemiology, not in a comorbidities
  section: the Disease class has no comorbidity slot, and a two-disease
  association carrying its own statistics belongs in kb/comorbidities/ as its own
  file. The record there is deliberately separate from differential_diagnoses,
  which lists conditions to exclude before making the diagnosis.

  Evidence discipline. Three claims in this entry carry recorded contradiction
  rather than a selected winner: mast cell involvement (SUPPORT and REFUTE on one
  node), the two commonest drugs (REFUTE on the primary endpoint, SUPPORT on a
  secondary one for desipramine), and the free-testosterone measurement in the
  androgen receptor study, which runs opposite to the hypothesis it was offered
  to support.
review_notes: >-
  Created in response to issue #7837, which has listed vulvodynia as absent from
  the knowledge base since 2026-08-24. No stub existed for MONDO:0021722 and no
  claim issue was open. The only prior mention of the concept anywhere in kb/ was
  a phenotype binding of HP:0030943 inside Vulvar_Carcinoma, which describes
  vulvar pain as a cancer symptom and is unrelated.

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