Pituitary hyperplasia with Sertoli cell-only and 47,XYY syndromes: an uncommon triad.

We report the case history of a 32-year-old man with no phenotypical abnormalities who presented with infertility. Semen analysis revealed azoospermia and testicular biopsy confirmed Sertoli cell-only (SCO) syndrome. Karyotyping revealed 47,XYY and pituitary hyperplasia was found on MRI pituitary. In our patient, 47,XYY karyotype is likely to have given rise to SCO syndrome that in turn resulted in pituitary hyperplasia. The patient was evaluated by various members of the multidisciplinary team including the pituitary surgeon, endocrinologist and andrologist. The patient's partner successfully delivered a healthy baby via in vitro fertilisation with donor sperm. This triad of diagnoses (SCO syndrome, 47,XYY karyotype and pituitary hyperplasia) has not been reported previously. SCO syndrome should be considered in the presence of azoospermia, elevated follicle-stimulating hormone, low inhibin-B and normal testosterone levels. Our case report also highlights the importance of excluding genetic causes of infertility even when the patient has no phenotypical abnormalities. © BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.