ESPE Abstracts

Introduction: Patients with congenital adrenal hyperplasia (CAH) develop advanced bone age (BA) frequently. Treatment with aromatase inhibitors can slow down bone maturation and improve final height in cases of CAH. However, safety is not clear at this point.

Case Presentation N 1 15.5 yrs. old boy was diagnosed with congenital adrenal hyperplasia, salt-wasting type at 4.9 years of age. His genetic analysis revealed that he didn’t have functional CYP21A2 gene: Allele1: 30 kb Deletion and Allele 2: 30 Kb deletion. He was treated with Cortef 10 mg/m² and Florinef 0.2 mg (2 tablets) daily. At 4.6 years his bone age was 6.6 yrs. However, at 6.9 yrs. BA became 13 yrs., which could severely jeopardize his final height. His Target Height was around 176 cm at the 48 percentile. Treatment with aromatase inhibitor Letrozole 2.5 mg daily was initiated to slow down bone maturation. On Letrozole bone maturation slowed down, so at 7.9 yrs. BA was 13 yrs. and at 13.6 yrs. BA was 13.6 yrs. On his recent visit at 15.5 yrs. BA was 14.6 yrs. At this point, he was treated with Letrozole 2.5 mg daily for 8.5 yrs. His testosterone was normal 639 ng/dl (Nl. 350-970). At 11.4 yrs. his Z-score for the Lumbar spine was normal 0.8, the subtotal body Z-score was 0. At 14.4 yrs. his Z-score for the Lumbar spine was normal -0.5. The subtotal bone Body Z-score was -1.3, which corresponded to the 90th percentile for his age.

Case Presentation N 2 Brother was diagnosed with congenital adrenal hyperplasia, salt-wasting type at birth. He carried the same deletions and didn’t have a functional CYP21A2 gene. He was treated with Cortef 8 mg/m² and Florinef 0.1 mg daily. At 10.6 yrs. his BA was advanced to 14 yrs. Treatment with Letrozole 2.5 mg daily started at 10.6 yrs. The last bone age at 12.6 yrs. revealed the same bone age 14 yrs., 2 yrs. after initiating treatment with Letrozole. Bone mineral density was obtained 1 yr. after beginning of the therapy at 11.6 yrs. and was normal. The Z-score for the lumbar spine was -1.5. The subtotal body Z-score was -1.7, normal, at the 88 percentile. His testosterone was normal for his stage of puberty 30 ng/ml.

Conclusion. Letrozole treatment can slow down bone maturation, and improve predicted adult height. Bone density was normal after 8.5 years of treatment with letrozole.