Successful treatment of pituitary gigantism

Pituitary gigantism is extremely rare, resulting from excessive secretion of growth hormone (GH) before fusion of epiphysial growth plates. We report a case of a 13-year-old boy, who presented with increased statural growth and headaches since the age of 10 years. On physical examination, his height was 180.7 cm (+3.3 SD) and Tanner stage V. Investigation revealed increased levels of serum age-adjusted and sex-adjusted insulin-like growth factor 1 (IGF-1) and failure of GH suppression during an oral glucose tolerance test (OGTT). MRI of the sellar region revealed a pituitary macroadenoma. He underwent transsphenoidal surgery and histopathological evaluation revealed mammosomatotropic adenoma. Three months after surgery, IGF-1 normalised, nadir GH during OGTT was less than 1 ng/mL and no residual tumour was found on the MRI. Genetic testing identified a mutation in the AIP gene. This case emphasises the importance of early diagnosis of gigantism, as treatment delay increases long-term morbidity.