[C1 inhibitor deficiency. Heredity and acquired forms. Symptoms, diagnostic and therapeutic problems]

C1 inhibitor deficiency can be hereditary (Type I and II) or acquired (Type I and II). Clinically it is manifested by recurrent attacks of angioedema which may involve skin, airways and digestive tract. The acquired form of C1 inhibitor deficiency is associated with lymphoproliferative or connective tissue disorders as well as with autoimmunization. Clinical symptoms are similar in all forms of C1 inhibitor deficiencies and they are connected with low serum level of C4 as well as with decreased activity of C1 inhibitor. In acquired angioedema additionally they are also decreased C1 and C1q and in type II C3 serum concentration is diminished. The drugs of choice are anabolics (danazol, stanazolol). Antifibrinolitic drugs are also used, especially in acquired forms of C1 inhibitor deficiency. The infusion of C1 inhibitor concentrate is used in acute emergency treatment.