Normal Bone Mineral Content in Young Adults with Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency

OBJECTIVE: To assess bone mineral content (BMC) and body composition in adolescents and young adults with congenital adrenal hyperplasia. METHODS: BMC, anteroposterior-projected bone area (BA), bone mineral density, and fat mass percentage were determined by dual-energy X-ray absorptiometry in 18 patients aged 18-33 years (8 females and 10 males) with 21-hydroxylase deficiency using a Hologic QDR 1000/W densitometer. RESULTS: BMC and bone mineral density for age were significantly reduced at -1.2 standard deviation scores (SDS; range from -2.8 to +4.1) and -1.1 SDS (range from -3.2 to +2.6), respectively. The BA for height was significantly increased at +1.7 SDS (range from -0.5 to +4.8), and the BMC for BA was normal at 0.3 SDS (range from -2.0 to +3.6). The median final height was significantly reduced at -1.6 SDS (range from -5.6 to +0.3), and the fat mass percentage was significantly increased at +1.5 SDS (range from -1.0 to +5.0). CONCLUSION: Our study population of young adults with 21-hydroxylase deficiency had a short stature and broad bones with a normal BMC and had an increased fat mass percentage.