The incidence of congenital adrenal hyperplasia in Switzerland--a survey of patients born in 1960 to 1974.

The incidence of congenital adrenal hyperplasia (CAH) in Switzerland was calucated for patients born in 1960 to 1974. Information was obtained by means of questionnaires sent to all Pediatric Hospitals and Institutes of Pathology in Switzerland. The number of patients and the incidences of the different enzyme defects were: all cases 110 (1:13785 livebirths), 21-hydroxylase 98 (1:15472), 11 beta-hydroxylase 5 (1:303260), 3 beta-dehydrogenase 3 (1:505433). The incidence of females--which is 1:12098 for all cases and 1:13924 for 21-hydroxylase deficiency--presumably appropximates more exactly the real incidence, because of incomplete diagnosis in the male. Salt loss was observed in two thirds of patients with 21-hydroxylase deficiency. A more reliable estimate of the incidence of CAH could be obtained by neonatal screening programs with measurement of serum-17-hydroxyprogesterone.