Classical Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency in Croatia between 1995 and 2006

Abstract

Aims: To evaluate the incidence, gender, symptoms and age at diagnosis among patients with classical congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency in Croatia. Methods: Data were collected retrospectively for all classical CAH patients born or electively aborted following prenatal diagnosis between 01.01.1995 and 31.12.2006 and were compared with the data of the previously conducted study evaluating CAH patients discovered between 1964 and 1984. Results: During a 12-year period, 34 classical CAH patients were born. There were 20 salt-wasting (SW) (12 females/8 males) and 14 simple virilizing (SV) patients (7 females/7 males). If 3 female fetuses, electively aborted, were added, that would be a total of 37 CAH patients. With 532,942 live births and 34 CAH patients born over this period, incidence of classical CAH was estimated to 1:15,574 or 1:14,403 if 3 electively aborted fetuses were included. The lower incidence of SW boys compared to SW girls (8:12) and similar number of SW and SV boys (8:7) indicate that substantial proportion of SW boys die unrecognized. Owing to better health care, diagnosis was established significantly earlier in SW and SV girls compared to the period of 1964–1984 (p < 0.003). During 1995–2006, none of the patients died following the diagnosis of CAH, and there was no erroneous sex assignment. Conclusion: Despite of improvement in health care, diagnosis of CAH in Croatia is still delayed and some of the patients go unrecognized or die. Therefore, we think that the results of our study support the need for the introduction of newborn screening.