Persistent Mullerian duct syndrome: An atypical clinical presentation

INTRODUCTION: Persistent Müllerian duct syndrome (PMDS) is a rare sexual development disorder characterized by a normal male phenotype. Müllerian structures cannot regress due to the absence of anti-müllerian hormone (AMH) or resistance to AMH receptor. In addition to male internal genitalia, female reproductive organs, including the uterus, uterine tubes, and upper 1/3 of the vagina are also detected. We will present a patient with PMDS who presented with bilateral cryptorchidism. CLINICAL CASE: A 31-year-old single man was referred to our clinic because of bilateral undescended testes and a rudimentary uterus detected during the evaluation of the lower abdominal pain. On physical examination, his body mass index (BMI) was 21.2. His arm span was 170 cm, and his upper-lower segment ratio was 0.96. Beard, axilla, and pubic hair development were normal; however, testes were not in the scrotum bilaterally. His karyotype analysis was 46XY. His prenatal, natal, and postnatal histories were not remarkable. His parents were not consanguineous; the younger brother had a history of undescended testis operation at age one. In laboratory examination, blood glucose, renal and liver functions were normal. Androstenedione, DHEAS, total and free testosterone, FSH, LH, total-hCG, AFP were normal. AMH>9µg/L. In the spermiogram, no sperm was observed. A rudimentary uterus and proximal vagina were observed in the abdominal computed tomography (CT). Symmetric solid masses measuring 55×40 mm compatible with bilateral undescended testis were detected in the ovarian lodges. The mass extended to the inguinal canal on the left and the scrotum on the right. In association with these masses, there were also tubular structures with the biggest diameter of 16 mm on the right and 13 mm on the left. Prostate sizes were normal. Seminal vesicles were not observed. PMDS was considered owing to 46 XY karyotypes, normal testosterone level, normal sexual development, external genitalia findings, accompanying Mullerian structures, and a high level of AMH. AMH gene mutation was not detected. However, AMH receptor type 2(AMHR2) gene mutation could not be studied. Bilateral undescended testicles, uterus, uterine tubes, and the tubular structures in the abdomen were excised. Classical type seminoma with lympho-vascular invasion was detected in the right-side tubular structure. Tumor-negative testicular tissue was frozen for possible fertility in the future. The patient received one cycle of Carboplatin. No metastasis was detected in the post-operative PET-CT scan. In post-operative evaluation, FSH, LH levels were high, total and free testosterone levels were low. AMH < 0.01 µg/L. The patient was started on testosterone replacement therapy. CONCLUSION: PMDS is a rare cause of male pseudo-hermaphroditism. Malignant degeneration and infertility are two critical points in terms of treatment. Early diagnosis with increased awareness is essential in preserving fertility and preventing malignant degeneration.