9. Sexual Aspects of Klinefelter's Syndrome and other Sex-Chromosome Disorders

Summary

KLINEFELTER SYNDROME (KS), first described in 1942 on the basis of testicular failure, occurs in one of 500 to one of 1000 males and is characterized by the abnormal karyotype 47,XXY. The KS phenotype is highly variable, but generally includes testicular failure, tall stature, and characteristic cognitive differences, such as language-based learning disabilities and reading dysfunction. It has been recently reported that, in adulthood, most men with KS will visit their physicians because of 1) infertility and/or 2) sexual dysfunction, suggesting that the clinical setting for the management of sexual problems is a convenient site for the diagnosis of KS. Sexual symptoms eventually present in KS have been demonstrated to be not specifically associated with the syndrome but to the underlying hypogonadal state. Further studies are needed to evaluate the efficacy of testosterone substitution in ameliorating the hypoactive sexual desire often reported in subjects with KS.