Abstract
Klinefelter Syndrome is the most common sex chromosomal disorder in males. The clinical features of Klinefelter syndrome are characterized by significant testicular dysfunction, hypogonadal symptoms, atrophic testes and gynecomastia . These patients can apply to the physician with symptoms specific to the syndrome or general symptoms. In addition to specific physical examination findings, the hormone profile is consistent with primary hypogonadism. The definitive diagnosis is made by karyotype analysis of peripheral blood lymphocytes. Early diagnosis and treatment are important. With hormone replacement therapy, muscle mass, bone mineral density and libido are improved. In general, patients with Klinefelter Syndrome are infertile, but fertilization can be achieved with assisted reproductive techniques. We present a case with dyspeptic symptoms and suspected physical examination findings and diagnosed as Klinefelter Syndrome.