Paediatric management of endocrine complications in McCune-Albright syndrome

McCune-Albright syndrome was diagnosed at 2.5 years in a male, with a lower limb fracture and café-au-lait markings. Polyostotic fibrous dysplasia was treated with pamidronate for 4 years, with control of bone pain, improved quality of life, normal growth and visual fields monitored 4-6 monthly. Gonadotrophin independent precocious puberty occurred between ages 5-7 years but was slowly progressive, requiring no treatment. Bone age was 9 years at 7.5 years. From age 8-8.5 years, growth velocity increased further, with widening of spaces between teeth, acral enlargement, sweating and facial acne but no change in pubertal status (testes 6 ml, pubic hair Tanner stage I). Binasal field loss occurred. MRI demonstrated a bulging pituitary gland typical of adolescence, with no discrete tumour, with a markedly thickened calvarium and sphenoid. Bone age advanced from 9 to 12 years in 1 year. Basal growth hormone (GH) was 78 mIU/l, rising to 100 mIU/l with glucose tolerance test, basal IGF-I 2.4 IU/l, FSH <0.1 mIU/l, LH 0.1 mIU/l, testosterone 1.4 nmol/l. Treatment with octreotide LAR, flutamide and testolactone resulted in control of GH (12 mIU/l) and precocious puberty, slowing of growth, return to normal jaw size and tooth spacing, sweating, acne, facial appearance and restoration of full visual fields. Response demonstrated short-term efficacy of medical treatment and a remarkable capacity for facial remodelling in a child with acromegaly. Visual field change is attributed to reduction in soft tissue swelling around the optic foramina. Management issues concern long-term control of GH secretion, the impracticability of surgery in this patient and radiotherapy concerns in a young child.