Endocrine Abstracts

Introduction: 11β-Hydroxylase deficiency is the second most common form of congenital adrenal hyperplasia (CAH) occurring in 1 in 100 000 births. The mainstay of management is with glucocorticoids to prevent virilisation and optimise growth. In this case, a novel approach was applied to improve linear growth in a patient who presented late with an advanced bone age.

Case report: The patient was born in Turkey to consanguineous parents. Aged 3 years, he was found to have pubic hair and a bone age of 8 years. Hormonal profiles confirmed a diagnosis of 11β-hydroxylase deficient CAH and he was treated with hydrocortisone.

On arrival in the UK aged 6 years, his pubertal staging was G3, P3 with 2 ml testes and he was hypertensive (146/98). His bone age was 14 years with a height of 131 cm. The predicted final height was 140 cm (mid-parental height 166 cm). His height velocity was poor (2.2 cm/year). Genetic analysis revealed a mutation in exon 5 of the CYP11B1 gene.

His dose of hydrocortisone was increased from 9 to 20 mg/m² per day and his dose of enalapril was increased. In an attempt to optimise his final height, at age 7 years, he was given GH (0.9 mg/m² per day) and the aromatase inhibitor anastrazole (1 mg o.d.) to prevent further bone age progression.

With this novel treatment, his height velocity increased to 10.5 cm/year. Currently, at age 12 years, his pubertal staging is G4, P4 with 8 ml testes. His height is 159 cm and he is still growing at a height velocity of 6 cm/year.

Conclusion: The predicted final height in a patient with CAH and an advanced bone age was significantly exceeded following treatment with GH and anastrazole. This treatment has not been previously reported to be effective in short children with CAH. Further research into the effectiveness and long-term safety of this treatment would be beneficial.