Klinefelter's syndrome is the most common genetically determined cause of male infertility. It is also connected with higher risk of many diseases such as cardiovascular disorders and malignant tumors as breast cancer and germinal tumors. As a consequence of phenotypic variability, still the majority of cases remains undiagnosed.
Case report: 24 years old male who was admitted to the department because of an episode of sudden resting dyspnoea with the coexisting pain in the retrosternal region and a state of anxiety. Performed examinations did not confirm the diagnosis of heart muscle dysfunction and pulmonary embolism either. However, we noticed the constellation of the specific phenotype features of this patient: high stature, gynecomastia, abdominal obesity, poor hair growth in genital regions. The hormonal tests were performed that allowed to diagnose the hypergonadotropic hypogonadism. Cytogenetic examination revealed the abnormal karyotype of 47,XXY.
Conclusions: There are no clear references as to diagnosing the Klinefelter's syndrome. Probably, like in this case report, in the majority of cases the diagnosis is accidental.