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Pathophysiology Nodes

5
5 shared nodes are defined in this module.
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Cell Types

1
Thyroid Follicular Cell CL:0002258 Cell Ontology (CL) Relation: this mechanism module involves this cell type This mechanism module involves Thyroid Follicular Cell (CL:0002258). CL:0002258 is a cell type from the Cell Ontology.
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Biological Processes

4
Thyroid Hormone Generation GO:0006590 ↓ DECREASED Gene Ontology (GO) Relation: this mechanism module involves this biological process This mechanism module involves decreased Thyroid Hormone Generation (GO:0006590). GO:0006590 is a biological process from the Gene Ontology. Thyroid Hormone Metabolic Process GO:0042403 ↓ DECREASED Gene Ontology (GO) Relation: this mechanism module involves this biological process This mechanism module involves decreased Thyroid Hormone Metabolic Process (GO:0042403). GO:0042403 is a biological process from the Gene Ontology. Response to Thyroid Hormone GO:0097066 ↓ DECREASED Gene Ontology (GO) Relation: this mechanism module involves this biological process This mechanism module involves decreased Response to Thyroid Hormone (GO:0097066). GO:0097066 is a biological process from the Gene Ontology. Regulation of Metabolic Process GO:0019222 ↓ DECREASED Gene Ontology (GO) Relation: this mechanism module involves this biological process This mechanism module involves decreased Regulation of Metabolic Process (GO:0019222). GO:0019222 is a biological process from the Gene Ontology.
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Notes

This is a mechanism module, not a specific disease. Disorder entries reference individual nodes via conforms_to (e.g., "hypothyroidism_thyroid_hormone_deficiency#Thyroid Hormone Insufficiency"). Conforming nodes should substitute the disorder-specific cause of reduced hormone synthesis: autoimmune thyroiditis, iodine deficiency, dyshormonogenesis (TPO/TG/NIS/DUOX2 defects), or central hypothyroidism (in which low TSH rather than the compensatory rise distinguishes the feedback arm).
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Used By Disorder Entries

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Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence-backed metadata.
Pathograph: causal mechanism network for Hypothyroidism Thyroid Hormone Deficiency Module Interactive directed graph showing how this shared module's pathophysiology nodes connect.
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Pathophysiology

5
Impaired Thyroid Hormone Synthesis
trigger
The conserved initiating lesion is impaired synthesis of thyroid hormone by thyroid follicular cells, whether from autoimmune destruction of the gland, inadequate iodine substrate, or genetic defects in the hormone biosynthetic machinery. Iatrogenic causes (thyroidectomy, radioiodine, antithyroid drugs) act at the same point.
Thyroid Follicular Cell CL:0002258 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves Thyroid Follicular Cell (CL:0002258). CL:0002258 is a cell type from the Cell Ontology.
Thyroid Hormone Generation GO:0006590 ↓ DECREASED Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased Thyroid Hormone Generation (GO:0006590). GO:0006590 is a biological process from the Gene Ontology.
Show evidence (2 references)
PMID:27936530 SUPPORT Other
"Primary hypothyroidism typically is a result of autoimmune thyroiditis or iodine deficiency and is assessed by measurement of the thyroid-stimulating hormone (TSH) level."
Identifies autoimmune thyroiditis and iodine deficiency as the principal causes of impaired hormone synthesis, the conserved initiating lesion. Evidence source is OTHER because this is a review article.
PMID:37641994 SUPPORT Other
"The leading causes of hypothyroidism in older adults are iatrogenic, Hashimoto's thyroiditis, and medications."
Confirms the spectrum of upstream causes (iatrogenic, autoimmune, drug-induced) that converge on reduced hormone synthesis. Evidence source is OTHER because this is a narrative review.
Thyroid Hormone Insufficiency
amplifier
Reduced synthesis lowers circulating T4 and T3. In primary hypothyroidism the loss of negative feedback drives a compensatory rise in pituitary thyroid-stimulating hormone (TSH), the biochemical hallmark used in diagnosis.
Thyroid Hormone Metabolic Process GO:0042403 ↓ DECREASED Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased Thyroid Hormone Metabolic Process (GO:0042403). GO:0042403 is a biological process from the Gene Ontology.
Show evidence (1 reference)
PMID:27936530 SUPPORT Other
"This level usually is elevated in patients with hypothyroidism and low in patients with hyperthyroidism."
Describes the compensatory TSH elevation that signals thyroid hormone insufficiency in primary hypothyroidism. Evidence source is OTHER because this is a review article.
Reduced Thyroid Hormone Action at Peripheral Sites
central effector
Insufficient circulating hormone reduces thyroid hormone signaling and action in peripheral target tissues. Because thyroid hormone metabolism and activity decline together, target tissues throughout the body receive diminished thyroid hormone stimulus.
Response to Thyroid Hormone GO:0097066 ↓ DECREASED Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased Response to Thyroid Hormone (GO:0097066). GO:0097066 is a biological process from the Gene Ontology.
Show evidence (1 reference)
PMID:37641994 SUPPORT Other
"Thyroid function declines over time due to physiological changes in the thyroid stimulating hormone signaling, iodine absorption and metabolism, thyroid hormone metabolism, and activity at peripheral sites."
Identifies thyroid hormone activity at peripheral sites as a component of thyroid function whose decline mediates the systemic effects of hormone deficiency. Evidence source is OTHER because this is a narrative review.
Decreased Metabolic Rate
effector
Thyroid hormone is a principal regulator of basal metabolic rate. Reduced peripheral hormone action lowers cellular and whole-body metabolism, the core physiological deficit of hypothyroidism.
Regulation of Metabolic Process GO:0019222 ↓ DECREASED Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves decreased Regulation of Metabolic Process (GO:0019222). GO:0019222 is a biological process from the Gene Ontology.
Show evidence (1 reference)
PMID:27936530 SUPPORT Other
"Hypothyroidism is a state of thyroid hormone insufficiency that results in decreased metabolism and secondary effects including fatigue and weight gain."
Directly states that thyroid hormone insufficiency results in decreased metabolism, the effector step linking hormone deficiency to hypometabolism. Evidence source is OTHER because this is a review article.
Systemic Hypometabolic State
consequence
The clinical endpoint is a generalized hypometabolic state affecting nearly every organ system — manifesting as fatigue, cold intolerance, weight gain, bradycardia, and, when severe, myxedema. This multisystem hypofunction defines clinical hypothyroidism.
Show evidence (1 reference)
PMID:27936530 SUPPORT Other
"Thyroid disease affects nearly every organ system in the body."
Establishes the multisystem reach of thyroid dysfunction, consistent with the generalized hypometabolic consequence of hypothyroidism. Evidence source is OTHER because this is a review article.