Prepubertal Gynecomastia Due to Indirect Exposure to Nonformulary Bioidentical Hormonal Replacement Therapy: A Case Report.

Background: Gynecomastia is a disorder of the endocrine system characterized by an abnormal presence of a palpable unilateral or bilateral enlargement and proliferation of glandular ductal benign breast tissue in male individuals. This case discusses the medical implications of an unregulated, indirect exposure to nonformulary, bioidentical hormone replacement therapy in male children.
Case: An 8-year-old boy presented with prepubertal gynecomastia secondary to estrogen exposure from maternal use of bioidentical hormonal replacement therapy (the Wiley protocol). We review the literature on prepubertal gynecomastia secondary to exogenous estrogen exposure, evaluation, clinical surveillance of the pubertal development, and relevant short- and long-term implications.
Conclusion: Indirect exposure to nonformulary hormonal replacement in our case report was an etiologic factor in the development of prepubertal gynecomastia. This novel estrogen exposure source has important implications in the differential diagnosis of prepubertal gynecomastia and potential adverse effects secondary to precocious hormonal exposure.