Complement Pathways
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Complement Pathways conditions
Early Complement Deficiencies (C1–C4)Early complement deficiencies C1–C4 impair classical pathway activation, increasing susceptibility to autoimmune diseases and recurrent bacterial infections.Hereditary Angioedema (C1 Esterase Inhibitor Deficiency)Hereditary angioedema due to C1 esterase inhibitor deficiency causes recurrent swelling attacks from unchecked bradykinin-mediated vascular permeability.Paroxysmal Nocturnal Hemoglobinuria (PNH)Paroxysmal Nocturnal Hemoglobinuria (PNH) is a rare acquired stem cell disorder causing complement-mediated red blood cell destruction, leading to hemolysis and thrombosis.Terminal Complement Deficiencies (C5–C9)Terminal Complement Deficiencies (C5–C9) involve impaired formation of the membrane attack complex, increasing susceptibility to Neisseria infections and recurrent meningococcal disease.