aetiology

Last reviewed 10/2021

Hereditary C1 esterase inhibitor deficiency is due to a defective gene on chromosome 11. Two types of hereditary C1 esterase inhibitor deficiency have been described:

• type I is characterized by low antigenic and functional levels of C1 esterase inhibitor (85% of cases)
• type II is characterized by normal or increased antigenic levels of C1 esterase inhibitor with low levels of functionally active protein (15% of cases)

Acquired C1 esterase inhibitor deficiency is an autoimmune disease which may be associated with systemic lupus erythematosus.

Reference:

• 1. Zuraw B.L. Hereditary angioedema. NEJM 2008: 359:1027-1036