A boy with prepubertal gynecomastia, hyperprolactinemia, and hypothyroidism.

Non-physiologic prepubertal gynecomastia with an identifiable cause is an uncommon condition. Hyperprolactinemia due to hypothyroidism is known to result in gynecomastia in adults, but this observation has not been reported in children. We discuss here a boy who developed gynecomastia after the first year of age and was later diagnosed with congenital hypothyroidism.