ESPE Abstracts

Background: Children with congenital adrenal hyperplasia (CAH) need chronic glucocorticoid therapy, both to replace congenital deficit in cortisol synthesis and to suppress the overproduction of androgens by the adrenal cortex. High doses of glucocorticoid taken chronically might affect bone metabolism and lead to alterations of bone mass in this condition. In particular, they could increase bone resorption rate. Bone mineral density (BMD) by energy X-ray absorptiometry ( DEXA ) scan is a very strong predictor of bone strength and biochemical markers of bone formation and turnover have been developed to look at bone metabolism.

Aim: The aim of the present work was to assess the effect of glucocorticoid replacement therapy ( hydrocortisone or prednisone) in children with CAH on growth and bone mineral density.

Subjects: The present study was conducted on 60 children (2 groups): Group 1 included 30 children, diagnosed with congenital adrenal hyperplasia attending the Endocrinology Clinic in Alexandria University Children's Hospital.Group 2 included 30 healthy children matching in age and sex as controls.

Methods: Careful history taking and thorough clinical examination stressing on anthropometric measurements. Pubertal status was assessed by Tanner staging. Laboratory investigations as calcium profile (corrected calcium for albumin, serum phosphorus, and alkaline phosphatase function), serum 17-OH progesterone and serum osteocalcin level were done. BMD was done by dual-energy X-ray absorptiometry (DEXA scan) of the lumbar spine.

Results: Serum osteocalcin level it was significantly lower in the patient's group (50.28ng/ml) than in the controls group (80.53ng/ml) with P value <0.001. (Table 6).Twenty patients (66.7%) were found to have normal BMD (Z score > -1 SD) while 6 patients (20%) were found to have osteoporosis (Z score <-2 SD) and 4 patients (13.3%) had osteopenia (Z score from -1 to -2 SD).22 patients (73.3%) were treated by prednisone and 8 patients (26.7%) were treated by hydrocortisone. There was no significant difference in growth, biochemical parameters and BMD between children receiving prednisone and children receiving hydrocortisone. BMD had significant positive correlation with serum osteocalcin level (r=0.475, P=0.008) and negative correlation with both alkaline phosphatase level (r =-0.460, P=0.011) and serum 17OH progesterone (r =-376, P=0.040).

Conclusions: Children with CAH may have reduced BMD and increase bone turnover compared with controls.