ESPE Abstracts

Objective: To investigate the feasibility and rationality of letrozole (Lz) as treatment for severely advanced bone age (BA) in children with 21-Hydroxylase Deficiency (21-OHD).

Methods: This was a retrospective self-control study to test the possibility of Lz that a decrease in the rate of bone maturation and an increase in predicted adult height (PAH).

Results: The improvement of height SDS for BA (Ht-SDSBA) andΔBA/ΔCA were both significantly increased after 12 months of adding Lz. PAH in boys was significantly increased after 12 months of adding Lz, which was delayed improvement in girls, and the PAH in boys and girls were both increased more than 10cm after 24 months. There were no severe interferences in sex hormones and hydrocortisone (HC) dosage, and no unacceptable adverse effects. Eventually 7 patients who reached or nearly reached final adult height (FAH). The total course of letrozole was (7.2±2.1) years, and the average FAH in boys were (169.2±4.3)cm, which in girls were (158.9±2.0)cm. The FAH-SDS for BA was (-0.28±0.60), that has reached the normal range.

Conclusion: Treatment with Lz delays bone maturation and improves PAH and FAH in children with 21-OHD.