The Hidden Uterus: Persistent Müllerian Duct Syndrome Unmasked by an Inguinal Hernia with Associated Testicular Neoplasia

A mutation in anti-Müllerian hormone or its receptor causes persistent Müllerian duct syndrome (PMDS), a rare condition in which male patients retain female reproductive organs. We report the case of a 35-year-old man with a history of left undescended testis, left-sided inguinal hernia, mental retardation, and normal external genitalia. On clinical examination, both testes were not palpable. Initial sonography revealed that the hernia sac contained mesentery and bowel, with no abnormality identified. However, follow-up computed tomography (CT) imaging revealed two testes-like structures—one in the left inguinal canal and the other in the left hernial sac—along with a uterus-like structure. Intraoperative findings confirmed the presence of the uterus and ovotestes, and histopathological analysis identified these structures as Müllerian sac remnants. The patient underwent bilateral gonadectomy, hysterectomy, and left inguinal herniorrhaphy with an uneventful postoperative recovery. This case demonstrates the critical role of CT imaging in the diagnosis of PMDS, a rare disorder, and highlights the importance of considering PMDS in patients with cryptorchidism and inguinal hernia, especially when initial sonographic results are benign.