Abstract
Disorders of sex development are genetically complex, and phenotypes range from hypospadias to completely masculinized or feminized genitalia with a discordant karyotype. They arise as a result of alterations in gonad formation (sex determination stage) or function (sex differentiation stage). Reaching a specific diagnosis with the aid of molecular technologies is important for individualized management, genetic counseling, and prognostic prediction for fertility and risk of tumor development. This case report describes a young adult male who was referred initially with concern for Klinefelter syndrome based on a commercial genetic test. His laboratory investigations revealed hypergonadotropic hypogonadism, azoospermia, and a chromosomal karyotype of 46,XX. He was eventually diagnosed with 46,XX testicular disorder of sex development. He was initiated on testosterone replacement therapy and offered adoption and use of donor sperm for artificial reproduction techniques.