ESPE Abstracts

Background: McCune–Albright syndrome (MAS) is a complex disorder characterized by the triad of fibrous dysplasia of multiple bones, café-au-lait skin macules and endocrinopathies.

Objective and hypotheses: Long-term treatment of a boy with gigantism due to MAS.

Method: Case report.

Results: We present the clinical course of a now 14 years old boy with MAS and GH excess, clinical signs of precocious puberty and hyperprolactinemia. He presented at the age of 5 years with a complicated bone fracture of the femur. Histological bone examination revealed fibrous dysplasia. On clinical examination, large café-au-lait macules were found, leading to the diagnosis of MAS. Cerebral MRI displayed generalized fibrous dysplasia of his skull base surrounding the pituitary gland and his facial bones. Ultrasound of his testes showed bilateral microlithiasis. At that time, clinical and biochemical evaluation showed no abnormalities besides a height of +2.2 SDS, in particular no precocious puberty or GH excess. At the age of 8.5 years, he was readmitted to due to increased growth velocity and signs of precocious puberty. Clinically, he presented with pubic hair Tanner III, testicular volume of 4 and 5 ml, and height of +2.9 6SDS. Bone age was advanced by 18 months, now. Further, IGF1, IGFBP3, and prolactin (PRL) were also markedly increased whereas hormones of thyroid and adrenal gland were normal. Therefore, a GH- and PRL-suppression therapy with somatostatine and cabergoline was started. After initiation of this therapy, his growth velocity markedly decreased, with suppression of GH and PRL. After about 4 years of successful therapy, GH and PRL increased again and stayed high during the last 12 months despite repetitive dose adjustments. Now, introduction of pegvisomant, a GH receptor antagonist, is planned to optimize pharmacological treatment.

Conclusion: Pharmacological treatment of MAS remains challenging during adolescence, especially in regard of adequate growth and increased risk of complications in future.