Diagnosis and Management of Precocious Puberty in Atypical Presentations of McCune-Albright Syndrome: A Case Series Review

Abstract Background McCune-Albright syndrome is a rare syndrome, classically defined as the triad of precocious puberty, fibrous dysplasia of bone, and cafe au lait lesions. Partial or atypical presentations of McCune-Albright syndrome, with only one or two of the classic symptoms, have been described in the literature and remain particularly challenging due to lack of diagnostic phenotype. In these patients, the utility of analysis of mutations in the gene of the α subunit of the stimulatory G-protein is limited and so the diagnosis is often based on clinical judgment. Three atypical cases of suspected McCune-Albright syndrome with gonadotropin-independent precocious puberty are presented. Cases Case #1: A 5-year-old female presented with painlesss vaginal bleeding and was found to have cafe au lait lesions. She was diagnosed with gonadotropin independent precocious puberty with eventual progression to gonadotropin dependent precocious puberty which was successfully treated with both letrozole and gonadotropin-releasing hormone agonist therapy. Case #2: A 3-year-old female presented with painless vaginal bleeding and was found to have cafe au lait lesions. She was diagnosed with gonadotropin independent precocious puberty and was successfully treated with letrozole. Case #3: A 5-year-old female presented with fibrous dysplasia and was found to have evidence of uterine and ovarian enlargement on ultrasound. She was diagnosed with gonadotropin-independent precocious puberty and was successfully treated with letrozole. Summary and Conclusion Although different in presentation, all three atypical cases of suspected McCune-Albright syndrome with gonadotropin-independent precocious puberty were successfully treated with aromatase inhibitors. This small case series shows the utility and efficacy of aromatase inhibitors in the setting of atypical cases of suspected MAS with gonadotropin-independent precocious puberty.