Familial occurrence of C1-inhibitor deficiency and the effect of treatment.

Seventy one persons (67 children and 4 of their mothers) who came to the out-patient department of our hospital because of recurrent edemas of subcutaneous tissue and mucous membranes were the subjects of study. Serum haemolytic activity of complement and concentration of C1-esterase inhibitor, C1q, C4 and C3 were measured. Twenty six persons were related: altogether 12 families were studied, mostly sisters and brothers. In six patients (k 8.5% of the group studied) inherited type I defect of C1-inhibitor was detected and the diagnosis of angioneurotic edema confirmed. The results of complement determination in these patients (5 girls and 1 mother) were compared to the rest of the group and to healthy blood donors and showed clear differences in concentrations of C1-inhibitor, C1q, C4 and in haemolytic activity. Treatment consisted of fibrinolysis inhibitor, epsilon-aminocaproic acid and of antihistamine drugs. The value of this kind of therapy in the treatment of a very well responding child is discussed.