Endocrine Abstracts

Introduction: 46 XX testicular DSD (disorder of sex development) is a rare syndrome characterized by 46 XX karyotipe, male external genitalia, azoospermia, sterility and usually hypergonadotropic hypogonadism in adulthood. Approximately 85% of individuals present after puberty with normal penile size, small testes and gynecomastia.

Case report: We present a 34-year-old male who was referred for endocrine evaluation due to slightly high prolactin levels. He underwent surgical correction of bilateral inguinal hernia at the age of 1.8 years old. Three years later, surgery was needed to descend trapped right testicle, showing testicular atrophy. At age 33, the patient requested medical evaluation after one year unsuccessfully attempting to father a pregnancy. Erectile dysfunction and lack of libido were not present. Semen analysis revealed azoospermia. Serum hormone evaluation detected high gonadotropines, low-normal testosterone and normal prolactin levels: LH 13,9 mIU/ml, FSH 32.11 mIU/ml, prolactin 15 ng/ml [4–15], testosterone 311.20 ng/dl [250–836]. Physical examination revealed a descended left testicle of 12 cm³ and a right testicle unnoticed to palpation. There was no hypospadias and penile size was within the normal range. Patient’s height and weight was 177 cm and 70 kg, respectively. Klinefelter syndrome was suspected. Cytogenetic procedures demonstrated a 46 XX kariotype, and the presence of SRY gene on one of the X comosomes was detected by fluorescent in situ hibrydization.

Conclusions: 46 XX testicular DSD SRY-positive should also be considered in the differential diagnosis of adult hypergonadotropic hypogonadism with small testes and sterility. Adult diagnosis can be challenging because of normal sexual development and phenotypic similarities between patients with 46 XX DSD and Klynefelter syndrome, althought the latter are usually taller and show less incidence of cryptorchidism.