Steinert disease and Klinefelter syndrome association.

Hypogonadism is common in Steinert disease but may also suggest other diagn oses. We report the case of a patient with Steinert's disease who also had Klinefelter syndrom disclosed at 62 years of age by an osteoporotic fractur e. Both clinical diagnoses were confirmed by karyotype and genetic analysis . The hypogonadism assigned to the Klinefelter syndrome for this patient ma y have influenced the clinical expression of the muscular pathology.