A case of McCune Albright syndrome in the context of an ovarian mass and late development of café-au-lait macules

Abstract

McCune-Albright syndrome (MAS) is a genetic disorder characterized by polyostotic fibrous dysplasia, precocious puberty, and café-au-lait spots. In this case, a patient presented with precocious puberty in the setting of an ovarian mass and late development of café-au-lait macules, confounding the final diagnosis of MAS. A 3-year-old girl presented with vaginal bleeding. She had a previous episode of vaginal bleeding, breast budding, and a right ovarian cyst at 5 months of age. Work-up at that time showed no abnormal findings, though past medical history was notable for two fractures. Physical exam was significant for increased height (89th percentile), increased weight (99th percentile), bilaterally elevated breast mounds with palpable breast tissue and darkened areolae (Tanner stage 3), and residual blood in the vaginal introitus. Notable labs included low FSH and high ultrasensitive estradiol. Pelvic MRI showed a right ovarian cyst, which, in the context of precocious puberty, raised the suspicion for a juvenile granulosa cell tumor. Follow-up pelvic MRI demonstrated features that instead suggested an ovarian response to hormonal stimulation. On a subsequent visit several months later, the patient had small café-au-lait macules on the chest and right buttock, which were not present on the initial evaluation. Further workup revealed advanced bone age on an x-ray at 6 years 10 months, and multifocal polyostotic fibrous dysplasia involving bilateral femurs and right tibia. Failure to include MAS in the differential had led to unnecessary oophorectomy. It is crucial to identify MAS as a cause of peripheral precocious puberty to guide proper management.