ESPE Abstracts

Key Words: Congenital Adrenal Hyperplasia, Advanced bone age, Aromatase inhibitors, Predicted Adult Height

Introduction: Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD) is characterized by cortisol and mineralocorticoid deficiency with excess adrenal androgen production. Standard treatment includes glucocorticoid and mineralocorticoid replacement. Slightly supraphysiological glucocorticoid replacement aims to reduce androgen load to maintain adequate growth, but adult height is often reduced due to the aromatisation of excess androgens into oestrogens causing growth acceleration with early epiphysial fusion at the growth plate. Aromatase inhibitors (AI) are a potential adjunct treatment in CAH to improve compromised predicted adult height (PAH) in the presence of significantly advanced bone age.

Aim: To describe growth-related parameters in five CAH patients with significantly advanced bone age, treated with non-steroidal AI, Anastrozole or Letrozole in addition to standard of care.

Results: Five male patients had genetically confirmed non-salt-wasting CAH diagnosed between two and six years of age. Bone age (BA) was advanced by 9.3 Standard Deviations (SD) (range 4.2-17.4) compared to chronological age at diagnosis. AI was started as an adjunct therapy at the age of 9.6, 7.25, 5, 3.5, 5years for the patients A, B, C, D and E in addition to gonadotropin releasing hormone analogue therapy to suppress biochemically confirmed central precocious puberty. Patients received AI for a mean period of 40.25 months (range 26-52). Mean BA was+6 SD (range 3.6-11.3) after 24 months of treatment. The mean BA improvement was 3.5 SD and the PAH has improved by 10-16cm for more than 24 months of treatment. Throughout the treatment period, bone mineral density, liver function and lipid profile remained normal.

Conclusions: AI may help as an adjuvant therapy in improving PAH by delaying bone maturation in children with CAH due to 21-OHD in the presence of significantly advanced BA without significant short term adverse effects. Larger multi-centre studies are required to validate the efficacy and safety, including evaluation of long-term adverse effects.