A case of gradually manifesting McCune-Albright syndrome with a 10-year follow-up

McCune-Albright syndrome (MAS) is characterized by fibrous dysplasia (FD) of bone, café-au-lait skin pigmentation, and precocious puberty. Here we report a case of a 12-year-old girl with MAS presenting sexual precocity as initial signs, followed by FD of bone with her growth. She was referred to our hospital because of breast budding and abnormal genital bleeding at the age of 2.8 years. On physical examination, her height and weight were greater than two standard deviations of the mean ranges. Hormonal analysis revealed an elevated serum estradiol and suppressed luteinizing hormone and follicle-stimulating hormone production. Her bone age had advanced, and a 16-mm monocystic lesion was observed on her right ovary by pelvic ultrasonography. Considering the clinical and paraclinical findings, precocious pseudopuberty was suspected and periodic observations were started. Her estrogen "flare up" was transient and she had repeated similar episodes three times in the following 7 years. She complained of pain in her right hip at the age of 9.6 years, which was diagnosed as FD of bone by fluorodeoxyglucose-positron emission tomography. Although no café-au-lait skin pigmentation was observed, we made a preliminary diagnosis of MAS. Because clinical evidence for MAS can appear later in the course of recurrent autonomous cysts, careful observation and periodical assessments of patients with suspected MAS is necessary.