Acquired deficiency of the inhibitor of the first complement component: presentation, diagnosis, course, and conventional management.

Acquired deficiency of the inhibitor of the first complement component (C1-INH) is a rare, potentially life-threatening disease whose cause, course, and management are not completely defined. This article analyzes the etiopathogenetic mechanism, the clinical presentation, and the relationship between acquired C1-INH deficiency and lymphoproliferative disorders. Moreover, the authors give an overview of the outcome of the disease and the different therapies proposed to cure it.