Campylobacteriosis - Disorder Mechanisms

🏷

Classifications

Harrison's Chapter

📘

Definitions

2

Clinical spectrum case definition for Campylobacter jejuni/coli infection

Campylobacteriosis is clinically classified into gastrointestinal disease and extraintestinal/post-infectious manifestations.

CASE_DEFINITION Clinical categorization of symptomatic Campylobacter jejuni/coli infection

Show evidence (1 reference)

DOI:10.3390/microorganisms12122669 SUPPORT Other

"The clinical spectrum of Campylobacter jejuni/coli infection can be classified into two distinct categories: gastrointestinal and extraintestinal manifestations."

Supports a two-category clinical case framing that distinguishes intestinal disease from extraintestinal complications.

Stool testing diagnostic framework

Diagnostic confirmation relies on stool testing with culture and molecular assays, while standalone antigen tests should be interpreted cautiously.

DIAGNOSTIC_CRITERIA Routine microbiologic diagnosis of suspected campylobacteriosis

Show evidence (2 references)

PMID:26962088 SUPPORT Human Clinical

"We conducted a prospective, multicenter study to evaluate the performance of stool antigen CIDTs compared to culture and PCR for Campylobacter detection."

Supports culture and PCR as core confirmatory diagnostic methods.

PMID:26962088 SUPPORT Human Clinical

"Given the relatively low incidence of Campylobacter disease and the generally poor diagnostic test characteristics, this study calls into question the use of commercially available stool antigen CIDTs as standalone tests for direct detection of Campylobacter in stool."

Supports avoiding standalone antigen CIDT use without confirmatory methods.

⚙

Pathophysiology

8

Exposure to contaminated food or water

Infection is initiated by ingestion of Campylobacter from contaminated foods, untreated water, or animal-associated sources.

Show evidence (1 reference)

DOI:10.3390/microorganisms12122669 SUPPORT Other

"Campylobacter infection is primarily transmitted through the consumption of contaminated food, especially uncooked meat, or untreated water; contact with infected animals or contaminated environments; poultry is the primary reservoir and source of human transmission."

Supports the initiating exposure event.

Chemotactic navigation through intestinal mucus

C. jejuni motility enables directional migration through mucus to reach epithelial targets.

small intestine link

Show evidence (1 reference)

DOI:10.1007/s00253-023-12456-w SUPPORT Other

"Chemotactically controlled motility in viscous milieu allows targeted navigation to intestinal mucus and colonization."

Supports mucus penetration and early colonization.

CadF/FlpA-mediated epithelial adhesion

Campylobacter adhesins bind fibronectin on polarized epithelial cells, triggering host signaling needed for invasion.

enterocyte link

small intestine link

Show evidence (1 reference)

DOI:10.1007/s00253-023-12456-w SUPPORT Other

"Fibronectin at the basolateral side of polarized epithelial cells serves as binding site for adhesins CadF and FlpA, leading to intracellular signaling, which again triggers membrane ruffling and reduced host cell migration by focal adhesion."

Supports adhesion-linked host signaling as a discrete upstream event.

Type III/VI secretion-dependent invasion signaling

Campylobacter relies on type III and type VI secretion-associated programs to establish an intestinal niche and potentiate host-cell invasion.

type III protein secretion system link

Show evidence (1 reference)

DOI:10.3390/biom13010135 SUPPORT Other

"We conclude that C. jejuni does not possess a type IV secretion system and relies on the type III and type VI secretion systems to establish a niche and potentiate disease."

Supports secretion-system dependence as a mechanistic step.

HtrA-mediated junctional protein cleavage

Bacterial HtrA protease activity cleaves tight/adherens junction components, compromising epithelial integrity.

cell junction organization link tight junction disassembly link

colon link

Show evidence (1 reference)

DOI:10.3390/cells13030224 SUPPORT In Vitro

"We recently discovered that C. jejuni serine protease HtrA disrupts intestinal epithelial barrier functions via cleavage of the tight and adherens junction components occludin, claudin-8 and E-cadherin."

Supports HtrA cleavage as an unbundled barrier-disruption event.

Paracellular transmigration and barrier dysfunction

Loss of epithelial junctional integrity allows Campylobacter to cross epithelial barriers and expand tissue-level injury.

Show evidence (1 reference)

DOI:10.3390/cells13030224 SUPPORT In Vitro

"Instead, we found that only bacteria with active protein biosynthesis effectively cleave junctional proteins, which is followed by paracellular transmigration of C. jejuni through the epithelial cell layer."

Directly supports causal linkage from junction cleavage to transmigration.

Mucosal inflammatory response and epithelial injury

Host inflammatory responses and epithelial lesions produce fluid/blood loss and symptomatic enteritis.

neutrophil link

inflammatory response link pyroptosis link

Show evidence (1 reference)

DOI:10.1007/s00253-023-12456-w SUPPORT Other

"Lesions of the epithelium result in loss of electrolytes, water, and blood, leading to diarrhea, which flushes out mucus containing C. jejuni."

Supports causal transition from epithelial injury to clinical gastrointestinal manifestations.

Post-infectious immune sequelae

Some patients develop delayed extraintestinal immune-mediated complications after acute Campylobacter infection.

Show evidence (1 reference)

DOI:10.3390/microorganisms12122669 SUPPORT Other

"Late complications are reactive arthritis, Guillain–Barré syndrome, and Miller Fisher syndrome."

Supports recognized post-infectious complications.

✶

Histopathology

2

Tight and adherens junction protein cleavage

Intestinal epithelial barrier injury includes cleavage of occludin, claudin-8, and E-cadherin by Campylobacter-associated protease activity.

Show evidence (1 reference)

DOI:10.3390/cells13030224 SUPPORT In Vitro

"We recently discovered that C. jejuni serine protease HtrA disrupts intestinal epithelial barrier functions via cleavage of the tight and adherens junction components occludin, claudin-8 and E-cadherin."

Supports a specific microscopic epithelial junctional injury pattern in campylobacteriosis.

Epithelial lesions with fluid and blood loss

Mucosal epithelial lesions are associated with loss of electrolytes, water, and blood during acute enteritis.

Show evidence (1 reference)

DOI:10.1007/s00253-023-12456-w SUPPORT Other

"Lesions of the epithelium result in loss of electrolytes, water, and blood, leading to diarrhea, which flushes out mucus containing C. jejuni."

Supports tissue-level epithelial lesion pathology linked to diarrheal and bloody stool manifestations.

⬡

Causal Graph

graph LR
    Exposure_to_contaminated_food_or_water["Exposure to contaminated food or water"]
    Bloody_diarrhea["Bloody diarrhea"]
    Guillain_Barre_syndrome["Guillain-Barre syndrome"]
    CadF_FlpA_mediated_epithelial_adhesion["CadF/FlpA-mediated epithelial adhesion"]
    Paracellular_transmigration_and_barrier_dysfunction["Paracellular transmigration and barrier dysfunction"]
    Chemotactic_navigation_through_intestinal_mucus["Chemotactic navigation through intestinal mucus"]
    Mucosal_inflammatory_response_and_epithelial_injury["Mucosal inflammatory response and epithelial injury"]
    Post_infectious_irritable_bowel_syndrome["Post-infectious irritable bowel syndrome"]
    Type_III_VI_secretion_dependent_invasion_signaling["Type III/VI secretion-dependent invasion signaling"]
    Abdominal_pain["Abdominal pain"]
    HtrA_mediated_junctional_protein_cleavage["HtrA-mediated junctional protein cleavage"]
    Post_infectious_immune_sequelae["Post-infectious immune sequelae"]
    Diarrhea["Diarrhea"]

    Exposure_to_contaminated_food_or_water --> Chemotactic_navigation_through_intestinal_mucus
    Chemotactic_navigation_through_intestinal_mucus --> CadF_FlpA_mediated_epithelial_adhesion
    CadF_FlpA_mediated_epithelial_adhesion --> Type_III_VI_secretion_dependent_invasion_signaling
    Type_III_VI_secretion_dependent_invasion_signaling --> HtrA_mediated_junctional_protein_cleavage
    HtrA_mediated_junctional_protein_cleavage --> Paracellular_transmigration_and_barrier_dysfunction
    Paracellular_transmigration_and_barrier_dysfunction --> Mucosal_inflammatory_response_and_epithelial_injury
    Mucosal_inflammatory_response_and_epithelial_injury --> Diarrhea
    Mucosal_inflammatory_response_and_epithelial_injury --> Bloody_diarrhea
    Mucosal_inflammatory_response_and_epithelial_injury --> Abdominal_pain
    Mucosal_inflammatory_response_and_epithelial_injury --> Post_infectious_immune_sequelae
    Post_infectious_immune_sequelae --> Guillain_Barre_syndrome
    Post_infectious_immune_sequelae --> Post_infectious_irritable_bowel_syndrome

    style Exposure_to_contaminated_food_or_water fill:#dbeafe
    style Bloody_diarrhea fill:#fef3c7
    style Guillain_Barre_syndrome fill:#fef3c7
    style CadF_FlpA_mediated_epithelial_adhesion fill:#dbeafe
    style Paracellular_transmigration_and_barrier_dysfunction fill:#dbeafe
    style Chemotactic_navigation_through_intestinal_mucus fill:#dbeafe
    style Mucosal_inflammatory_response_and_epithelial_injury fill:#dbeafe
    style Post_infectious_irritable_bowel_syndrome fill:#fef3c7
    style Type_III_VI_secretion_dependent_invasion_signaling fill:#dbeafe
    style Abdominal_pain fill:#fef3c7
    style HtrA_mediated_junctional_protein_cleavage fill:#dbeafe
    style Post_infectious_immune_sequelae fill:#dbeafe
    style Diarrhea fill:#fef3c7

●

Phenotypes

8

Digestive(2) Metabolism(1) Constitutional(1) Other(4)

Digestive 2

Diarrhea Diarrhea (HP:0002014)

Show evidence (1 reference)

DOI:10.3390/biom13010135 SUPPORT Other

"Campylobacter jejuni is likely the most common bacterial cause of gastroenteritis worldwide, responsible for millions of cases of inflammatory diarrhea characterized by severe abdominal cramps and blood in the stool."

Directly supports diarrhea as a cardinal phenotype.

Bloody diarrhea Bloody diarrhea (HP:0025085)

Show evidence (1 reference)

DOI:10.3390/biom13010135 SUPPORT Other

"Campylobacter jejuni is likely the most common bacterial cause of gastroenteritis worldwide, responsible for millions of cases of inflammatory diarrhea characterized by severe abdominal cramps and blood in the stool."

The abstract explicitly reports blood in stool, supporting bloody diarrhea.

Metabolism 1

Fever Fever (HP:0001945)

Show evidence (1 reference)

PMID:36635328 SUPPORT Human Clinical

"In summary, we found that nearly half of the patients with Campylobacter bacteremia presented with fever as a predominant manifestation without gastroenteritis symptoms."

Supports fever as a clinically important phenotype in systemic Campylobacter disease.

Constitutional 1

Abdominal pain Abdominal pain (HP:0002027)

Show evidence (1 reference)

DOI:10.3390/biom13010135 SUPPORT Other

"Campylobacter jejuni is likely the most common bacterial cause of gastroenteritis worldwide, responsible for millions of cases of inflammatory diarrhea characterized by severe abdominal cramps and blood in the stool."

Severe abdominal cramps correspond to abdominal pain.

Other 4

Guillain-Barre syndrome Guillain-Barre syndrome (MONDO:0016218)

Show evidence (2 references)

DOI:10.3390/microorganisms12122669 SUPPORT Other

"Late complications are reactive arthritis, Guillain–Barré syndrome, and Miller Fisher syndrome."

Supports Guillain-Barre syndrome as a recognized post-infectious complication.

PMID:36430700 SUPPORT Other

"C. jejuni is responsible for about a third of GBS cases."

Provides quantitative support that Campylobacter jejuni is a major trigger for Guillain-Barre syndrome.

Reactive arthritis reactive arthritis (MONDO:0017376)

Show evidence (1 reference)

PMID:40395728 SUPPORT Other

"As a consequence, infected individuals may acquire watery and/or bloody diarrhea associated with abdominal pain, and eventually post-infection illnesses of the neural system and joints, including the Guillain-Barré, Miller Fisher and Reiter syndromes."

Supports reactive arthritis (Reiter syndrome) as a post-infectious complication.

Miller Fisher syndrome Miller Fisher syndrome (MONDO:0005851)

Show evidence (1 reference)

PMID:40395728 SUPPORT Other

"As a consequence, infected individuals may acquire watery and/or bloody diarrhea associated with abdominal pain, and eventually post-infection illnesses of the neural system and joints, including the Guillain-Barré, Miller Fisher and Reiter syndromes."

Supports Miller Fisher syndrome as a recognized post-infectious neurologic sequela.

Post-infectious irritable bowel syndrome irritable bowel syndrome (MONDO:0005052)

Show evidence (1 reference)

PMID:20856114 SUPPORT Other

"Also patients with infectious colitis, in particular Salmonella and Campylobacter, are at increased risk of postinfectious irritable bowel syndrome and inflammatory bowel disease on long-term follow-up."

Supports PI-IBS as a recognized long-term sequela after Campylobacter-associated infectious colitis.

💊

Treatments

3

Targeted antibiotic therapy for severe intestinal infection MAXO:0000058

Antimicrobial therapy is recommended selectively for severe disease rather than routine mild gastroenteritis.

Show evidence (1 reference)

DOI:10.3390/microorganisms12122669 SUPPORT Other

"Regarding the use of specific antimicrobial therapy, international guidelines agree in recommending it for severe intestinal infections."

Supports severity-based use of antibiotics.

Resistance-informed antibiotic selection MAXO:0000058

High quinolone resistance with comparatively preserved macrolide susceptibility should guide empiric and definitive antibiotic choices.

Show evidence (3 references)

DOI:10.3390/antibiotics13090904 SUPPORT Other

"The analysis reveals a concerning trend of increasing resistance patterns, particularly to CIP and TET, across multiple regions."

Supports antimicrobial stewardship and local susceptibility-guided therapy.

PMID:37910310 SUPPORT Human Clinical

"Quinolone resistance was high (59%), whereas only 4% of isolates exhibited macrolide resistance."

Supports selecting agents based on resistance patterns, with quinolone resistance substantially exceeding macrolide resistance.

PMID:41566887 SUPPORT Human Clinical

"From our cohort of 331 patients over 3 years, there was 22% ciprofloxacin resistance and 100% susceptibility to erythromycin."

Supports preserved erythromycin susceptibility in a recent adult clinical cohort.

Intravenous antibiotic therapy for fever-predominant bacteremia MAXO:0000058

Fever-predominant bacteremic presentations often require intravenous antibiotics and longer treatment courses.

Show evidence (1 reference)

PMID:36635328 SUPPORT Human Clinical

"Patients with the FP type underwent intravenous antibiotic therapy more frequently (47.6% vs. 88.9%), and their treatment (median: 5 days vs. 13 days) and hospitalization (median: 7 days vs. 21 days) periods were significantly longer."

Supports escalation to intravenous antibiotic therapy with longer duration in fever-predominant bacteremic disease.

🌍

Environmental Factors

3

Poultry and raw milk food-exposure risk

Food handling and ingestion exposures involving undercooked poultry and unpasteurized dairy are major environmental drivers of campylobacteriosis.

Show evidence (1 reference)

PMID:40395728 SUPPORT Other

"In particular, the ingestion of under-cooked rooster meat, raw milk and contaminated water, as well as cross-contamination of ready-to-eat food after handling raw chicken meat, are responsible for the majority of C. jejuni infections."

Supports poultry, raw milk, and cross-contamination as dominant environmental acquisition risks.

Water-system and weather-associated contamination risk

Contaminated recreational/drinking water, treatment failures, and heavy rainfall events contribute to environmental transmission risk.

Show evidence (1 reference)

PMID:41280732 SUPPORT Other

"Recreational and drinking water sources were the most commonly implicated, with contamination events often associated with specific incidents or treatment failures, and heavy rainfall suggested as contributing factor to pathogen entry."

Supports environmental water-system vulnerabilities and weather-linked contamination pathways.

Host vulnerability context

Individual host factors influence risk of severe or prolonged disease after environmental exposure.

Show evidence (2 references)

PMID:30725718 SUPPORT Other

"Immunocompromised and elderly patients are at the highest risk for morbidity, mortality, and prolonged illness."

Supports host vulnerability as a modifier of disease severity and duration.

DOI:10.3390/microorganisms12122669 SUPPORT Other

"Host factors, including malnutrition, immunodeficiency, and malignancy, can also influence the decision to treat."

Supports host-risk context for clinically significant disease requiring treatment decisions.

🔀

Differential Diagnoses

2

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

Shigellosis MONDO:0019345

Overlapping Features Shigellosis can present with acute inflammatory diarrhea and abdominal pain similar to campylobacteriosis.

Distinguishing Features

Often associated with very low infectious dose and person-to-person spread.
Stool diagnostics with organism-specific culture/PCR can distinguish Shigella from Campylobacter.

Show evidence (1 reference)

PMID:20856114 SUPPORT Other

"The purpose of this review is to highlight the recent advances in knowledge of pathogens causing infectious colitis. We describe the various pathogens and specifically focus on enterohemorrhagic Escherichia coli (EHEC) O157:H7, Salmonella, Shigella, Campylobacter, and Entamoeba histolytica..."

Supports Shigella as a core alternate pathogen in the differential diagnosis of Campylobacter-associated infectious colitis.

Clostridioides difficile infection MONDO:0000705

Overlapping Features C. difficile colitis can mimic campylobacteriosis with diarrhea and abdominal pain, especially in recently antibiotic-exposed patients.

Distinguishing Features

Often linked to recent antibiotic exposure and healthcare-associated settings.
Toxin testing and organism-specific stool assays differentiate C. difficile from Campylobacter.

Show evidence (1 reference)

PMID:28613708 SUPPORT Other

"C difficile infections can range from an asymptomatic carrier to diarrhea, progressing to severe conditions such as pseudomembranous colitis and toxic megacolon with septic shock, often resulting in a high mortality rate."

Supports C. difficile as a clinically important diarrheal colitis differential that can mimic severe infectious enterocolitis presentations.

📊

Related Datasets

1

Gene expression analysis of rectal mucosa in chronic irritable bowel syndrome (IBS) compared to healthy volunteers (HV) geo:GSE36701

Microarray expression dataset including post-infectious context related to prior Campylobacter jejuni exposure.

human MICROARRAY n=93

rectal mucosa

Conditions: irritable bowel syndrome with diarrhea healthy volunteer controls post-infectious gastrointestinal phenotype context

PMID:33530940

https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE36701

Show evidence (1 reference)

PMID:33530940 SUPPORT Computational

"METHODS: Gene expression data (GSE36701) was downloaded from Gene Expression Omnibus database."

Confirms the GEO accession used for downstream bioinformatic analysis relevant to post-infectious gastrointestinal phenotypes.

🔬

Clinical Trials

2

NCT02280044 NOT_APPLICABLE COMPLETED

Randomized, double-blind, placebo-controlled inpatient human challenge study evaluating rifaximin prophylaxis against C. jejuni campylobacteriosis.

Target Phenotypes: Diarrhea ↗

Show evidence (1 reference)

clinicaltrials:NCT02280044 SUPPORT Human Clinical

"This study is a randomized, double-blinded, placebo-controlled, in-patient trial evaluating the prophylactic efficacy of rifaximin against campylobacteriosis following challenge with C. jejuni."

Demonstrates interventional trial evidence focused on prevention of Campylobacter-mediated diarrheal disease.

NCT06122870 PHASE_I COMPLETED

Double-blind, placebo-controlled human challenge study of hyperimmune bovine colostrum (CampETEC HBC) to prevent moderate-severe C. jejuni diarrheal disease.

Target Phenotypes: Diarrhea ↗

Show evidence (1 reference)

clinicaltrials:NCT06122870 SUPPORT Human Clinical

"The purpose of this study are to assess the safety and tolerability of serum-derived bovine immunoglobulins in healthy adult subjects when orally administered and to estimate protective efficacy of those preparations against moderate-severe diarrhea upon challenge with Campylobacter C. jejuni..."

Supports ongoing translational prevention strategy targeting Campylobacter challenge-associated diarrheal outcomes.

{ }

Source YAML

click to show

name: Campylobacteriosis
creation_date: '2026-02-26T22:44:59Z'
updated_date: '2026-03-01T20:00:32Z'
category: Infectious
description: >-
  A foodborne bacterial enteric infection, most commonly caused by Campylobacter jejuni
  and Campylobacter coli, characterized by acute inflammatory diarrhea and potential
  post-infectious sequelae.
disease_term:
  preferred_term: campylobacteriosis
  term:
    id: MONDO:0005688
    label: campylobacteriosis
parents:
- Bacterial enteritis
- Foodborne infection
synonyms:
- Campylobacter enteritis
- Campylobacter infection
classifications:
  harrisons_chapter:
  - classification_value: infectious disease
    evidence:
    - reference: DOI:10.3390/microorganisms12122669
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Campylobacteriosis is a leading cause of infectious diarrhea and foodborne illness worldwide."
      explanation: Supports classification of campylobacteriosis as an infectious disease.
  - classification_value: bacterial infectious disease
    evidence:
    - reference: DOI:10.3390/biom13010135
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Campylobacter jejuni is likely the most common bacterial cause of gastroenteritis worldwide, responsible for millions of cases of inflammatory diarrhea characterized by severe abdominal cramps and blood in the stool."
      explanation: Supports bacterial infectious disease classification for campylobacteriosis.
definitions:
- name: Clinical spectrum case definition for Campylobacter jejuni/coli infection
  definition_type: CASE_DEFINITION
  description: Campylobacteriosis is clinically classified into gastrointestinal disease and extraintestinal/post-infectious manifestations.
  scope: Clinical categorization of symptomatic Campylobacter jejuni/coli infection
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The clinical spectrum of Campylobacter jejuni/coli infection can be classified into two distinct categories: gastrointestinal and extraintestinal manifestations."
    explanation: Supports a two-category clinical case framing that distinguishes intestinal disease from extraintestinal complications.
- name: Stool testing diagnostic framework
  definition_type: DIAGNOSTIC_CRITERIA
  description: Diagnostic confirmation relies on stool testing with culture and molecular assays, while standalone antigen tests should be interpreted cautiously.
  scope: Routine microbiologic diagnosis of suspected campylobacteriosis
  evidence:
  - reference: PMID:26962088
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: We conducted a prospective, multicenter study to evaluate the performance of stool antigen CIDTs compared to culture and PCR for Campylobacter detection.
    explanation: Supports culture and PCR as core confirmatory diagnostic methods.
  - reference: PMID:26962088
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Given the relatively low incidence of Campylobacter disease and the generally poor diagnostic test characteristics, this study calls into question the use of commercially available stool antigen CIDTs as standalone tests for direct detection of Campylobacter in stool.
    explanation: Supports avoiding standalone antigen CIDT use without confirmatory methods.
infectious_agent:
- name: Campylobacter jejuni
  description: Primary Campylobacter species responsible for human campylobacteriosis.
  infectious_agent_term:
    preferred_term: Campylobacter jejuni
    term:
      id: NCBITaxon:197
      label: Campylobacter jejuni
  evidence:
  - reference: DOI:10.3390/biom13010135
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Campylobacter jejuni is likely the most common bacterial cause of gastroenteritis worldwide, responsible for millions of cases of inflammatory diarrhea characterized by severe abdominal cramps and blood in the stool."
    explanation: Supports C. jejuni as the dominant organism associated with campylobacteriosis burden.
- name: Campylobacter coli
  description: Secondary Campylobacter species that contributes to human campylobacteriosis.
  infectious_agent_term:
    preferred_term: Campylobacter coli
    term:
      id: NCBITaxon:195
      label: Campylobacter coli
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The clinical spectrum of Campylobacter jejuni/coli infection can be classified into two distinct categories: gastrointestinal and extraintestinal manifestations."
    explanation: Confirms C. coli as part of the clinically relevant Campylobacter infection spectrum.
transmission:
- name: Foodborne transmission
  description: Most human infections are acquired through ingestion of contaminated food, especially undercooked poultry and other contaminated meats.
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Campylobacter infection is primarily transmitted through the consumption of contaminated food, especially uncooked meat, or untreated water; contact with infected animals or contaminated environments; poultry is the primary reservoir and source of human transmission."
    explanation: Supports contaminated food as a primary transmission route.
- name: Waterborne transmission
  description: Campylobacter can be transmitted through consumption of untreated or contaminated water.
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Campylobacter infection is primarily transmitted through the consumption of contaminated food, especially uncooked meat, or untreated water; contact with infected animals or contaminated environments; poultry is the primary reservoir and source of human transmission."
    explanation: Supports untreated water as a distinct ingestion-mediated transmission route.
  - reference: PMID:41280732
    supports: SUPPORT
    evidence_source: OTHER
    snippet: Giardia and Campylobacter are two key waterborne pathogens and leading agents of gastrointestinal illnesses.
    explanation: Supports Campylobacter as a major waterborne gastrointestinal pathogen.
- name: Animal-contact transmission
  description: Zoonotic transmission can occur through direct contact with infected animals or contaminated animal-associated environments.
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Campylobacter infection is primarily transmitted through the consumption of contaminated food, especially uncooked meat, or untreated water; contact with infected animals or contaminated environments; poultry is the primary reservoir and source of human transmission."
    explanation: Supports animal-contact and contaminated-environment zoonotic transmission.
progression:
- phase: Incubation
  incubation_days: 2.5-4.3
  notes: Typical incubation distribution reported across outbreak and human experimental studies.
  evidence:
  - reference: PMID:28669361
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: The mean incubation period of subgroups ranged from 2·5 to 4·3 days.
    explanation: Supports the incubation window for campylobacteriosis.
- phase: Acute enteritis
  duration_days: 5-7
  notes: Most uncomplicated illness is self-limited.
  evidence:
  - reference: PMID:30725718
    supports: SUPPORT
    evidence_source: OTHER
    snippet: Patients typically experience a self-limited diarrheal illness lasting 5 to 7 days.
    explanation: Supports typical acute symptom duration.
- phase: Fever-predominant bacteremic presentation
  notes: A severe subset presents with fever without prominent gastrointestinal symptoms and often requires more intensive inpatient treatment.
  evidence:
  - reference: PMID:36635328
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: In summary, we found that nearly half of the patients with Campylobacter bacteremia presented with fever as a predominant manifestation without gastroenteritis symptoms.
    explanation: Supports a clinically distinct systemic presentation phase in severe Campylobacter infection.
  - reference: PMID:37910310
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: In-hospital mortality occurred in 14 (13.0%) patients.
    explanation: Supports clinically severe bacteremic presentations with measurable inpatient mortality risk.
- phase: Post-infectious sequelae
  notes: After acute enteric illness, a subset of patients develops delayed neurologic and rheumatologic complications.
  evidence:
  - reference: PMID:40395728
    supports: SUPPORT
    evidence_source: OTHER
    snippet: As a consequence, infected individuals may acquire watery and/or bloody diarrhea associated with abdominal pain, and eventually post-infection illnesses of the neural system and joints, including the Guillain-Barré, Miller Fisher and Reiter syndromes.
    explanation: Supports progression from acute gastrointestinal disease to delayed post-infectious extraintestinal sequelae.
pathophysiology:
- name: Exposure to contaminated food or water
  description: Infection is initiated by ingestion of Campylobacter from contaminated foods, untreated water, or animal-associated sources.
  downstream:
  - target: Chemotactic navigation through intestinal mucus
    description: Ingested organisms reach the intestinal lumen and begin colonization.
    evidence:
    - reference: DOI:10.1007/s00253-023-12456-w
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Chemotactically controlled motility in viscous milieu allows targeted navigation to intestinal mucus and colonization."
      explanation: Supports the causal transition from enteric exposure to active mucus navigation and colonization.
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Campylobacter infection is primarily transmitted through the consumption of contaminated food, especially uncooked meat, or untreated water; contact with infected animals or contaminated environments; poultry is the primary reservoir and source of human transmission."
    explanation: Supports the initiating exposure event.
- name: Chemotactic navigation through intestinal mucus
  description: C. jejuni motility enables directional migration through mucus to reach epithelial targets.
  locations:
  - preferred_term: small intestine
    term:
      id: UBERON:0002108
      label: small intestine
  downstream:
  - target: CadF/FlpA-mediated epithelial adhesion
    description: Mucus traversal positions bacteria for epithelial attachment.
    evidence:
    - reference: DOI:10.1007/s00253-023-12456-w
      supports: SUPPORT
      evidence_source: OTHER
      snippet: Fibronectin at the basolateral side of polarized epithelial cells serves as binding site for adhesins CadF and FlpA, leading to intracellular signaling, which again triggers membrane ruffling and reduced host cell migration by focal adhesion.
      explanation: Supports progression from colonization to CadF/FlpA-mediated epithelial adhesion.
  evidence:
  - reference: DOI:10.1007/s00253-023-12456-w
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Chemotactically controlled motility in viscous milieu allows targeted navigation to intestinal mucus and colonization."
    explanation: Supports mucus penetration and early colonization.
- name: CadF/FlpA-mediated epithelial adhesion
  description: Campylobacter adhesins bind fibronectin on polarized epithelial cells, triggering host signaling needed for invasion.
  cell_types:
  - preferred_term: enterocyte
    term:
      id: CL:0000584
      label: enterocyte
  locations:
  - preferred_term: small intestine
    term:
      id: UBERON:0002108
      label: small intestine
  downstream:
  - target: Type III/VI secretion-dependent invasion signaling
    description: Adhesion primes secretion-driven entry mechanisms.
    evidence:
    - reference: DOI:10.1007/s00253-023-12456-w
      supports: SUPPORT
      evidence_source: OTHER
      snippet: Cell contacts of C. jejuni results in its secretion of invasion antigens, which induce membrane ruffling by paxillin-independent pathway.
      explanation: Supports cell-contact/adhesion-dependent triggering of secretion-mediated invasion signaling.
  evidence:
  - reference: DOI:10.1007/s00253-023-12456-w
    supports: SUPPORT
    evidence_source: OTHER
    snippet: Fibronectin at the basolateral side of polarized epithelial cells serves as binding site for adhesins CadF and FlpA, leading to intracellular signaling, which again triggers membrane ruffling and reduced host cell migration by focal adhesion.
    explanation: Supports adhesion-linked host signaling as a discrete upstream event.
- name: Type III/VI secretion-dependent invasion signaling
  description: Campylobacter relies on type III and type VI secretion-associated programs to establish an intestinal niche and potentiate host-cell invasion.
  biological_processes:
  - preferred_term: type III protein secretion system
    term:
      id: GO:0030254
      label: protein secretion by the type III secretion system
  downstream:
  - target: HtrA-mediated junctional protein cleavage
    description: Secretion-associated virulence supports barrier-targeting invasion progression.
    evidence:
    - reference: DOI:10.1007/s00253-023-12456-w
      supports: SUPPORT
      evidence_source: OTHER
      snippet: C. jejuni utilizes proteases to open cell–cell junctions and subsequently transmigrates paracellularly.
      explanation: Supports transition from invasion-associated virulence programs to protease-mediated junction disruption.
  evidence:
  - reference: DOI:10.3390/biom13010135
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "We conclude that C. jejuni does not possess a type IV secretion system and relies on the type III and type VI secretion systems to establish a niche and potentiate disease."
    explanation: Supports secretion-system dependence as a mechanistic step.
- name: HtrA-mediated junctional protein cleavage
  description: Bacterial HtrA protease activity cleaves tight/adherens junction components, compromising epithelial integrity.
  biological_processes:
  - preferred_term: cell junction organization
    term:
      id: GO:0034330
      label: cell junction organization
  - preferred_term: tight junction disassembly
    term:
      id: GO:1905071
      label: tight junction disassembly
  locations:
  - preferred_term: colon
    term:
      id: UBERON:0001155
      label: colon
  downstream:
  - target: Paracellular transmigration and barrier dysfunction
    description: Junctional cleavage permits bacterial passage across the epithelial layer.
    evidence:
    - reference: DOI:10.3390/cells13030224
      supports: SUPPORT
      evidence_source: IN_VITRO
      snippet: "Instead, we found that only bacteria with active protein biosynthesis effectively cleave junctional proteins, which is followed by paracellular transmigration of C. jejuni through the epithelial cell layer."
      explanation: Supports direct causal linkage between junctional cleavage and paracellular transmigration.
  evidence:
  - reference: DOI:10.3390/cells13030224
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: We recently discovered that C. jejuni serine protease HtrA disrupts intestinal epithelial barrier functions via cleavage of the tight and adherens junction components occludin, claudin-8 and E-cadherin.
    explanation: Supports HtrA cleavage as an unbundled barrier-disruption event.
- name: Paracellular transmigration and barrier dysfunction
  description: Loss of epithelial junctional integrity allows Campylobacter to cross epithelial barriers and expand tissue-level injury.
  downstream:
  - target: Mucosal inflammatory response and epithelial injury
    description: Barrier breach amplifies host inflammatory signaling and epithelial damage.
    evidence:
    - reference: DOI:10.1007/s00253-023-12456-w
      supports: SUPPORT
      evidence_source: OTHER
      snippet: The immune system reacts with an inflammatory cascade by participation of numerous immune cells.
      explanation: Supports progression from epithelial barrier compromise to tissue inflammatory injury.
  evidence:
  - reference: DOI:10.3390/cells13030224
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "Instead, we found that only bacteria with active protein biosynthesis effectively cleave junctional proteins, which is followed by paracellular transmigration of C. jejuni through the epithelial cell layer."
    explanation: Directly supports causal linkage from junction cleavage to transmigration.
- name: Mucosal inflammatory response and epithelial injury
  description: Host inflammatory responses and epithelial lesions produce fluid/blood loss and symptomatic enteritis.
  cell_types:
  - preferred_term: neutrophil
    term:
      id: CL:0000775
      label: neutrophil
  biological_processes:
  - preferred_term: inflammatory response
    term:
      id: GO:0006954
      label: inflammatory response
  - preferred_term: pyroptosis
    term:
      id: GO:0070269
      label: pyroptotic inflammatory response
  downstream:
  - target: Diarrhea
    description: Epithelial damage and fluid/electrolyte loss drive diarrheal output.
    evidence:
    - reference: DOI:10.1007/s00253-023-12456-w
      supports: SUPPORT
      evidence_source: OTHER
      snippet: Lesions of the epithelium result in loss of electrolytes, water, and blood, leading to diarrhea, which flushes out mucus containing C. jejuni.
      explanation: Supports the causal relationship between epithelial injury and diarrheal output.
  - target: Bloody diarrhea
    description: Mucosal injury and inflammatory colitis contribute to blood in stool.
    evidence:
    - reference: DOI:10.3390/biom13010135
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Campylobacter jejuni is likely the most common bacterial cause of gastroenteritis worldwide, responsible for millions of cases of inflammatory diarrhea characterized by severe abdominal cramps and blood in the stool."
      explanation: Supports blood in stool as a direct downstream manifestation of inflammatory enteritis.
  - target: Abdominal pain
    description: Inflammatory enteritis and tissue injury contribute to cramping pain.
    evidence:
    - reference: DOI:10.3390/biom13010135
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Campylobacter jejuni is likely the most common bacterial cause of gastroenteritis worldwide, responsible for millions of cases of inflammatory diarrhea characterized by severe abdominal cramps and blood in the stool."
      explanation: Supports severe abdominal cramps as a downstream clinical manifestation.
  - target: Post-infectious immune sequelae
    description: Immune activation can persist beyond acute infection in a subset of patients.
    evidence:
    - reference: DOI:10.3390/biom13010135
      supports: SUPPORT
      evidence_source: OTHER
      snippet: Further, C. jejuni infections are associated with post-infection sequelae in developed countries and malnutrition and growth-stunting in low- and middle-income countries.
      explanation: Supports progression from acute inflammatory disease to post-infectious sequelae.
  evidence:
  - reference: DOI:10.1007/s00253-023-12456-w
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Lesions of the epithelium result in loss of electrolytes, water, and blood, leading to diarrhea, which flushes out mucus containing C. jejuni."
    explanation: Supports causal transition from epithelial injury to clinical gastrointestinal manifestations.
- name: Post-infectious immune sequelae
  description: Some patients develop delayed extraintestinal immune-mediated complications after acute Campylobacter infection.
  downstream:
  - target: Guillain-Barre syndrome
    description: Post-infectious autoimmunity can manifest as peripheral neuropathy.
    evidence:
    - reference: PMID:36430700
      supports: SUPPORT
      evidence_source: OTHER
      snippet: C. jejuni is responsible for about a third of GBS cases.
      explanation: Supports Campylobacter-triggered post-infectious autoimmunity as a major contributor to Guillain-Barre syndrome.
  - target: Post-infectious irritable bowel syndrome
    description: Persistent gut dysfunction can follow infectious colitis in a subset of patients.
    evidence:
    - reference: PMID:20856114
      supports: SUPPORT
      evidence_source: OTHER
      snippet: Also patients with infectious colitis, in particular Salmonella and Campylobacter, are at increased risk of postinfectious irritable bowel syndrome and inflammatory bowel disease on long-term follow-up.
      explanation: Supports post-infectious IBS as a delayed sequela linked to Campylobacter enteric infection.
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Late complications are reactive arthritis, Guillain–Barré syndrome, and Miller Fisher syndrome."
    explanation: Supports recognized post-infectious complications.
histopathology:
- name: Tight and adherens junction protein cleavage
  description: Intestinal epithelial barrier injury includes cleavage of occludin, claudin-8, and E-cadherin by Campylobacter-associated protease activity.
  evidence:
  - reference: DOI:10.3390/cells13030224
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: We recently discovered that C. jejuni serine protease HtrA disrupts intestinal epithelial barrier functions via cleavage of the tight and adherens junction components occludin, claudin-8 and E-cadherin.
    explanation: Supports a specific microscopic epithelial junctional injury pattern in campylobacteriosis.
- name: Epithelial lesions with fluid and blood loss
  description: Mucosal epithelial lesions are associated with loss of electrolytes, water, and blood during acute enteritis.
  evidence:
  - reference: DOI:10.1007/s00253-023-12456-w
    supports: SUPPORT
    evidence_source: OTHER
    snippet: Lesions of the epithelium result in loss of electrolytes, water, and blood, leading to diarrhea, which flushes out mucus containing C. jejuni.
    explanation: Supports tissue-level epithelial lesion pathology linked to diarrheal and bloody stool manifestations.
phenotypes:
- name: Diarrhea
  description: Acute inflammatory diarrhea is the central clinical presentation of campylobacteriosis.
  phenotype_term:
    preferred_term: Diarrhea
    term:
      id: HP:0002014
      label: Diarrhea
  evidence:
  - reference: DOI:10.3390/biom13010135
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Campylobacter jejuni is likely the most common bacterial cause of gastroenteritis worldwide, responsible for millions of cases of inflammatory diarrhea characterized by severe abdominal cramps and blood in the stool."
    explanation: Directly supports diarrhea as a cardinal phenotype.
- name: Bloody diarrhea
  description: Invasive inflammatory disease may manifest with blood in stool.
  phenotype_term:
    preferred_term: Bloody diarrhea
    term:
      id: HP:0025085
      label: Bloody diarrhea
  evidence:
  - reference: DOI:10.3390/biom13010135
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Campylobacter jejuni is likely the most common bacterial cause of gastroenteritis worldwide, responsible for millions of cases of inflammatory diarrhea characterized by severe abdominal cramps and blood in the stool."
    explanation: The abstract explicitly reports blood in stool, supporting bloody diarrhea.
- name: Abdominal pain
  description: Patients commonly experience severe cramping abdominal pain during acute illness.
  phenotype_term:
    preferred_term: Abdominal pain
    term:
      id: HP:0002027
      label: Abdominal pain
  evidence:
  - reference: DOI:10.3390/biom13010135
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Campylobacter jejuni is likely the most common bacterial cause of gastroenteritis worldwide, responsible for millions of cases of inflammatory diarrhea characterized by severe abdominal cramps and blood in the stool."
    explanation: Severe abdominal cramps correspond to abdominal pain.
- name: Guillain-Barre syndrome
  description: A rare post-infectious autoimmune neuropathy occurring after Campylobacter infection.
  phenotype_term:
    preferred_term: Guillain-Barre syndrome
    term:
      id: MONDO:0016218
      label: Guillain-Barre syndrome
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Late complications are reactive arthritis, Guillain–Barré syndrome, and Miller Fisher syndrome."
    explanation: Supports Guillain-Barre syndrome as a recognized post-infectious complication.
  - reference: PMID:36430700
    supports: SUPPORT
    evidence_source: OTHER
    snippet: C. jejuni is responsible for about a third of GBS cases.
    explanation: Provides quantitative support that Campylobacter jejuni is a major trigger for Guillain-Barre syndrome.
- name: Fever
  description: Fever can occur during severe Campylobacter infection and may predominate in bacteremic presentations.
  phenotype_term:
    preferred_term: Fever
    term:
      id: HP:0001945
      label: Fever
  evidence:
  - reference: PMID:36635328
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: In summary, we found that nearly half of the patients with Campylobacter bacteremia presented with fever as a predominant manifestation without gastroenteritis symptoms.
    explanation: Supports fever as a clinically important phenotype in systemic Campylobacter disease.
- name: Reactive arthritis
  description: Reactive arthritis is a recognized post-infectious rheumatologic complication of campylobacteriosis.
  phenotype_term:
    preferred_term: reactive arthritis
    term:
      id: MONDO:0017376
      label: reactive arthritis
  evidence:
  - reference: PMID:40395728
    supports: SUPPORT
    evidence_source: OTHER
    snippet: As a consequence, infected individuals may acquire watery and/or bloody diarrhea associated with abdominal pain, and eventually post-infection illnesses of the neural system and joints, including the Guillain-Barré, Miller Fisher and Reiter syndromes.
    explanation: Supports reactive arthritis (Reiter syndrome) as a post-infectious complication.
- name: Miller Fisher syndrome
  description: Miller Fisher syndrome is a post-infectious neurologic complication associated with Campylobacter infection.
  phenotype_term:
    preferred_term: Miller Fisher syndrome
    term:
      id: MONDO:0005851
      label: Miller Fisher syndrome
  evidence:
  - reference: PMID:40395728
    supports: SUPPORT
    evidence_source: OTHER
    snippet: As a consequence, infected individuals may acquire watery and/or bloody diarrhea associated with abdominal pain, and eventually post-infection illnesses of the neural system and joints, including the Guillain-Barré, Miller Fisher and Reiter syndromes.
    explanation: Supports Miller Fisher syndrome as a recognized post-infectious neurologic sequela.
- name: Post-infectious irritable bowel syndrome
  description: A subset of patients develop chronic bowel dysfunction after resolved Campylobacter enteritis.
  phenotype_term:
    preferred_term: post-infectious irritable bowel syndrome
    term:
      id: MONDO:0005052
      label: irritable bowel syndrome
  evidence:
  - reference: PMID:20856114
    supports: SUPPORT
    evidence_source: OTHER
    snippet: Also patients with infectious colitis, in particular Salmonella and Campylobacter, are at increased risk of postinfectious irritable bowel syndrome and inflammatory bowel disease on long-term follow-up.
    explanation: Supports PI-IBS as a recognized long-term sequela after Campylobacter-associated infectious colitis.
epidemiology:
- name: United States annual burden estimate
  description: Estimated annual case burden remains high in the United States.
  unit: cases per year
  factors:
  - foodborne transmission
  evidence:
  - reference: PMID:30725718
    supports: SUPPORT
    evidence_source: OTHER
    snippet: According to the Centers for Disease Control (CDC), there are about 1.3 million cases of Campylobacter infection each year in the United States alone.
    explanation: Supports the large annual domestic case burden.
- name: Pediatric incidence concentration
  description: Young children represent the highest-incidence age group in many settings.
  factors:
  - age under 5 years
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: In the pediatric population, the 0–4 age group has the highest incidence of campylobacteriosis.
    explanation: Supports age-stratified incidence concentration in early childhood.
- name: Antimicrobial resistance pressure
  description: Increasing resistance, especially to fluoroquinolones and macrolides, affects treatment strategy and public health planning.
  factors:
  - fluoroquinolone resistance
  - macrolide resistance
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: The Centers for Disease Control and Prevention (CDC) has identified antibiotic resistance in Campylobacter as a ‘significant public health threat’ due to increasing resistance to FQs or macrolides.
    explanation: Supports AMR as a key epidemiologic pressure point.
prevalence:
- population: Global
  notes: Leading bacterial diarrheal and foodborne illness burden worldwide.
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Campylobacteriosis is a leading cause of infectious diarrhea and foodborne illness worldwide."
    explanation: Supports substantial global disease burden.
- population: United States
  notes: Annual burden is commonly reported as case counts rather than percent prevalence.
  evidence:
  - reference: PMID:30725718
    supports: SUPPORT
    evidence_source: OTHER
    snippet: According to the Centers for Disease Control (CDC), there are about 1.3 million cases of Campylobacter infection each year in the United States alone.
    explanation: Supports commonly cited annual case burden in the US.
- population: Finland domestic cases (pilot case-control study, 2022)
  percentage: 39
  evidence:
  - reference: DOI:10.3390/microorganisms12010132
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Based on the case-control study, we estimated that of all cases, 39% were of domestic origin."
    explanation: Provides a country-specific surveillance estimate from human case-control data.
diagnosis:
- name: Stool culture and molecular confirmation
  description: Campylobacter diagnosis is typically based on stool testing with culture and/or molecular assays.
  evidence:
  - reference: PMID:26962088
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: We conducted a prospective, multicenter study to evaluate the performance of stool antigen CIDTs compared to culture and PCR for Campylobacter detection.
    explanation: Supports culture/PCR as key diagnostic modalities in clinical stool testing.
- name: Avoid standalone stool antigen CIDTs
  description: Stool antigen assays show variable performance and should not be used as standalone diagnostics without confirmatory testing.
  evidence:
  - reference: PMID:26962088
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Given the relatively low incidence of Campylobacter disease and the generally poor diagnostic test characteristics, this study calls into question the use of commercially available stool antigen CIDTs as standalone tests for direct detection of Campylobacter in stool.
    explanation: Supports caution regarding standalone antigen-based diagnosis.
differential_diagnoses:
- name: Shigellosis
  description: Shigellosis can present with acute inflammatory diarrhea and abdominal pain similar to campylobacteriosis.
  disease_term:
    preferred_term: shigellosis
    term:
      id: MONDO:0019345
      label: shigellosis
  distinguishing_features:
  - Often associated with very low infectious dose and person-to-person spread.
  - Stool diagnostics with organism-specific culture/PCR can distinguish Shigella from Campylobacter.
  evidence:
  - reference: PMID:20856114
    supports: SUPPORT
    evidence_source: OTHER
    snippet: The purpose of this review is to highlight the recent advances in knowledge of pathogens causing infectious colitis. We describe the various pathogens and specifically focus on enterohemorrhagic Escherichia coli (EHEC) O157:H7, Salmonella, Shigella, Campylobacter, and Entamoeba histolytica infections, and their impact on long-term effects, including postinfectious irritable bowel syndrome and inflammatory bowel disease.
    explanation: Supports Shigella as a core alternate pathogen in the differential diagnosis of Campylobacter-associated infectious colitis.
- name: Clostridioides difficile infection
  description: C. difficile colitis can mimic campylobacteriosis with diarrhea and abdominal pain, especially in recently antibiotic-exposed patients.
  disease_term:
    preferred_term: Clostridium difficile colitis
    term:
      id: MONDO:0000705
      label: Clostridium difficile colitis
  distinguishing_features:
  - Often linked to recent antibiotic exposure and healthcare-associated settings.
  - Toxin testing and organism-specific stool assays differentiate C. difficile from Campylobacter.
  evidence:
  - reference: PMID:28613708
    supports: SUPPORT
    evidence_source: OTHER
    snippet: C difficile infections can range from an asymptomatic carrier to diarrhea, progressing to severe conditions such as pseudomembranous colitis and toxic megacolon with septic shock, often resulting in a high mortality rate.
    explanation: Supports C. difficile as a clinically important diarrheal colitis differential that can mimic severe infectious enterocolitis presentations.
environmental:
- name: Poultry and raw milk food-exposure risk
  description: Food handling and ingestion exposures involving undercooked poultry and unpasteurized dairy are major environmental drivers of campylobacteriosis.
  effect: Increases risk of primary gastrointestinal infection.
  evidence:
  - reference: PMID:40395728
    supports: SUPPORT
    evidence_source: OTHER
    snippet: In particular, the ingestion of under-cooked rooster meat, raw milk and contaminated water, as well as cross-contamination of ready-to-eat food after handling raw chicken meat, are responsible for the majority of C. jejuni infections.
    explanation: Supports poultry, raw milk, and cross-contamination as dominant environmental acquisition risks.
- name: Water-system and weather-associated contamination risk
  description: Contaminated recreational/drinking water, treatment failures, and heavy rainfall events contribute to environmental transmission risk.
  effect: Increases risk of waterborne Campylobacter outbreaks.
  evidence:
  - reference: PMID:41280732
    supports: SUPPORT
    evidence_source: OTHER
    snippet: Recreational and drinking water sources were the most commonly implicated, with contamination events often associated with specific incidents or treatment failures, and heavy rainfall suggested as contributing factor to pathogen entry.
    explanation: Supports environmental water-system vulnerabilities and weather-linked contamination pathways.
- name: Host vulnerability context
  description: Individual host factors influence risk of severe or prolonged disease after environmental exposure.
  effect: Increases probability of complicated clinical course and treatment need.
  evidence:
  - reference: PMID:30725718
    supports: SUPPORT
    evidence_source: OTHER
    snippet: Immunocompromised and elderly patients are at the highest risk for morbidity, mortality, and prolonged illness.
    explanation: Supports host vulnerability as a modifier of disease severity and duration.
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: Host factors, including malnutrition, immunodeficiency, and malignancy, can also influence the decision to treat.
    explanation: Supports host-risk context for clinically significant disease requiring treatment decisions.
treatments:
- name: Targeted antibiotic therapy for severe intestinal infection
  description: Antimicrobial therapy is recommended selectively for severe disease rather than routine mild gastroenteritis.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
  evidence:
  - reference: DOI:10.3390/microorganisms12122669
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Regarding the use of specific antimicrobial therapy, international guidelines agree in recommending it for severe intestinal infections."
    explanation: Supports severity-based use of antibiotics.
- name: Resistance-informed antibiotic selection
  description: High quinolone resistance with comparatively preserved macrolide susceptibility should guide empiric and definitive antibiotic choices.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
  evidence:
  - reference: DOI:10.3390/antibiotics13090904
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The analysis reveals a concerning trend of increasing resistance patterns, particularly to CIP and TET, across multiple regions."
    explanation: Supports antimicrobial stewardship and local susceptibility-guided therapy.
  - reference: PMID:37910310
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Quinolone resistance was high (59%), whereas only 4% of isolates exhibited macrolide resistance.
    explanation: Supports selecting agents based on resistance patterns, with quinolone resistance substantially exceeding macrolide resistance.
  - reference: PMID:41566887
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: From our cohort of 331 patients over 3 years, there was 22% ciprofloxacin resistance and 100% susceptibility to erythromycin.
    explanation: Supports preserved erythromycin susceptibility in a recent adult clinical cohort.
- name: Intravenous antibiotic therapy for fever-predominant bacteremia
  description: Fever-predominant bacteremic presentations often require intravenous antibiotics and longer treatment courses.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
  evidence:
  - reference: PMID:36635328
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Patients with the FP type underwent intravenous antibiotic therapy more frequently (47.6% vs. 88.9%), and their treatment (median: 5 days vs. 13 days) and hospitalization (median: 7 days vs. 21 days) periods were significantly longer."
    explanation: Supports escalation to intravenous antibiotic therapy with longer duration in fever-predominant bacteremic disease.
clinical_trials:
- name: NCT02280044
  phase: NOT_APPLICABLE
  status: COMPLETED
  description: Randomized, double-blind, placebo-controlled inpatient human challenge study evaluating rifaximin prophylaxis against C. jejuni campylobacteriosis.
  target_phenotypes:
  - preferred_term: Diarrhea
    term:
      id: HP:0002014
      label: Diarrhea
  evidence:
  - reference: clinicaltrials:NCT02280044
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: This study is a randomized, double-blinded, placebo-controlled, in-patient trial evaluating the prophylactic efficacy of rifaximin against campylobacteriosis following challenge with C. jejuni.
    explanation: Demonstrates interventional trial evidence focused on prevention of Campylobacter-mediated diarrheal disease.
- name: NCT06122870
  phase: PHASE_I
  status: COMPLETED
  description: Double-blind, placebo-controlled human challenge study of hyperimmune bovine colostrum (CampETEC HBC) to prevent moderate-severe C. jejuni diarrheal disease.
  target_phenotypes:
  - preferred_term: Diarrhea
    term:
      id: HP:0002014
      label: Diarrhea
  evidence:
  - reference: clinicaltrials:NCT06122870
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: The purpose of this study are to assess the safety and tolerability of serum-derived bovine immunoglobulins in healthy adult subjects when orally administered and to estimate protective efficacy of those preparations against moderate-severe diarrhea upon challenge with Campylobacter C. jejuni strain CG8421.
    explanation: Supports ongoing translational prevention strategy targeting Campylobacter challenge-associated diarrheal outcomes.
datasets:
- accession: geo:GSE36701
  title: Gene expression analysis of rectal mucosa in chronic irritable bowel syndrome (IBS) compared to healthy volunteers (HV)
  description: Microarray expression dataset including post-infectious context related to prior Campylobacter jejuni exposure.
  organism:
    preferred_term: human
    term:
      id: NCBITaxon:9606
      label: Homo sapiens
  data_type: MICROARRAY
  sample_types:
  - preferred_term: rectal mucosa
    term:
      id: UBERON:0001155
      label: colon
    tissue_term:
      preferred_term: colon
      term:
        id: UBERON:0001155
        label: colon
  sample_count: 93
  conditions:
  - irritable bowel syndrome with diarrhea
  - healthy volunteer controls
  - post-infectious gastrointestinal phenotype context
  publication: PMID:33530940
  evidence:
  - reference: PMID:33530940
    supports: SUPPORT
    evidence_source: COMPUTATIONAL
    snippet: "METHODS: Gene expression data (GSE36701) was downloaded from Gene Expression Omnibus database."
    explanation: Confirms the GEO accession used for downstream bioinformatic analysis relevant to post-infectious gastrointestinal phenotypes.
  notes: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE36701