classic complement early component deficiency https://rarediseases.info.nih.gov/diseases/9526/complement-component-deficiency UMLS:C1285186 GARD:0009526 MEDGEN:226929 A genetic deficiency of any early component of the classical pathway (C1q, C1r/s, C2, C4, and C3) that is associated with autoimmune diseases due to the failure of clearance of immune complexes (IC) and apoptotic materials, and the impairment of normal humoral response. SCTID:363009005 genetic deficiency of early component of the classical complement pathway ICD9:279.8 MONDO:0000015 complement deficiency