A case of diabetes mellitus associated with Klinefelter's syndrome

Yoon, Ji Young; Hong, Sang Mo; Park, Yong Soo; Kim, Dong Sun; Choi, Woong Hwan; Kim, Tae Wha; Ahn, You Hern

Abstract

An increased frequency of diabetes or impaired glucose tolerance in Klinefelter's syndrome has been previously reported. Insulin resistance is considered to be the cause of this phenomenon in Klinefelter's syndrome, which is associated with low serum SHBG and sex hormone deficiency. Sex hormone deficiencies also result in dyslipidemia and metabolic syndrome. The interrelationship between diabetes, metabolic syndrome, and androgen deficiency is complex. Here we report a case of an 18-year-old man first diagnosed with diabetes mellitus 3 years ago. Upon physical examination the patient showed characteristic phenotypes compatible with primary hypogonadism. Subsequently, tests aimed at determining the cause of hypogonadism, including a chromosomal analysis, suggested Klinefelter's syndrome. The patient's HOMA-IR score was compatible with insulin resistance. Therefore, when diabetes mellitus develops at a young age with characteristic phenotypes, a careful history and physical examination may be needed to determine whether the patient might have primary hypogonadism caused by Klinefelter's syndrome.