PRENATAL MOLECULAR-GENETIC DIAGNOSIS AND TREATMENT OF CONGENITAL ADRENAL-HYPERPLASIA DUE TO 21-HYDROXYLASE DEFICIENCY

Congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21-OH ), in its severe forms, produces virilization of the external genitali a of the affected female fetus. Early treatment with dexamethasone of the pregnant mother at risk of a fetus with 21-OH deficiency avoids th e masculinization of the affected female fetus, We present a pregnant mother, where the prenatal diagnosis was established by DNA analysis o f a chorionic villous sample obtained in the 9th week of gestation. Mo lecular analysis showed the female fetus to be affected of 21-OH defic iency. Maternal treatment with dexamethasone started on the 6th week o f gestation has prevented the virilization of the affected baby. No si gnificant side effects have been encountered. Prenatal diagnosis and t reatment for 21-OH deficiency is effective and safe, as is described i n the literature. This is the first case in Spain where both prenatal molecular diagnosis and treatment for 21-OH deficiency have been repor ted.