complement component 3 deficiency
MONDO:0013417
A rare genetic disorder with an autosomal recessive pattern of inheritance. It is caused by the ineffective or decreased biosynthesis of the third complement component, C3. C3 deficiency may also be acquired acutely post-infection or chronically from co-morbid autoimmune disorders. If C3 is adequately synthesized, its rapid depletion may result in a functional deficiency. Clinical signs of the inherited deficiency present within the first decade of life and are consistent with the signs of recurrent systemic infection or immune complex disease. Deficiency of serum C3 and its major cleavage product, C3b, will decrease the effective humoral immune response to encapsulated bacteria. Deficiency of C3 also impairs clearance of circulating immune complexes and therefore predisposes to rheumatic and renal disease.
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Directly mapped studies only · unique clinical trialsCurrent registry observations. Phase counts may overlap. Study start dates are not registry registration dates. Investigational interventions are not approved-treatment recommendations.
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Complement 3 deficiency
Complement 3 deficiency is a genetic condition affecting complement component 3 (C3). People can suffer from either primary or secondary C3 deficiency. Primary C3 deficiency refers to an inherited autosomal-recessive disorder that involves mutations in the gene for C3. Secondary C3 deficiency results from a lack of factor I or factor H, two proteins that are key for the regulation of C3. Both primary and secondary C3 deficiency are characterized by low levels or absence of C3.
Background only. Canonical identity remains MONDO; clinical-trial relationships come from ClinicalTrials.gov.Drugs being studied
Disease identity and terminology: MONDO. Trial relationships: ClinicalTrials.gov.