PMON33 Non-Syndromic SRY Negative 46 XX Testicular Disorder of Sex Development (DSD); A rare cause of Infertility

INTRODUCTION: Male infertility can be categorized as endocrine and systemic disorders, primary testicular defects in spermatogenesis, sperm transport disorders and idiopathic male infertility. Chromosomal abnormalities are one of the primary testicular defects. The overall incidence of chromosome abnormalities in infertile men is estimated to be around 5.8%. XX male is a rare sex chromosomal disorder in infertile men. We present case of a young patient with infertility, azoospermia, hypergonadotropic hypogonadism and classical (46, XX) karyotype with negative FISH and SRY gene. Case report: 28-Year-old gentleman was referred to adult endocrinology clinic as part of work up for infertility. Initial work up included 2 semen analyses which were consistent with azoospermia. Examination revealed height 180 cm, weight 77 kg, a body mass index 24 kg/m2, normal phenotypic male without gynecomastia and had normal male pattern hair distribution. Genital examination showed normal male phallus without hypospadias, a hypoplastic scrotum, bilateral firm testes, with no varicocele or hydrocele. Labs were suggestive of compensated primary hypogonadism (FSH 47.9 mIU/ml, LH 20.4 mIU/ml, total testosterone 397.9 ng/dl by LC/MS, free testosterone 15.76 ng/dl by equilibrium dialysis, Inhibin B < 10 pg/ml, and anti-Mullerian hormone 0.390 ng/ml. Given normal testosterone levels, he was not started on testosterone replacement. Karyotype analysis revealed 46 XX and FISH was negative for SRY gene. CT imaging of abdomen and pelvis did not reveal any Mullerian structures, prostrate and seminal vesicles reported as normal. Patient met with a Urologist and was informed that testicular sperm extraction will not be a possibility for him. Patient had a detailed consultation with a geneticist for genetic and family counseling. Chromosome microarray analysis was obtained and was normal. Invitae Disorders of sex development (DSD) panel obtained for genetic sequencing of 53 genes including SOX-9, DHH, WNT4, WT1, was found to be non-diagnostic. CONCLUSION AND DISCUSSION: SRY negative 46 XX male is a DSD and a rare genetic cause of male factor infertility, with a discrepancy between genotype and phenotypic sex. In the case presented, genetic work up for potential etiologies has been unrevealing. Further studies are needed to identify the genetic causes of the SRY negative 46 XX male phenotype. Physicians involved in care of these patients should orient with clinical management and prognosis. For Classical 46 XX Males seeking fertility, the current options include invitro-fertilization with donor sperm or adoption only. Testosterone replacement should be considered to correct hypogonadism for physical and sexual well-being. Genetic consultation should be sought in all these cases. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.