Men's health

Raising awareness of a ‘hidden’ condition: Klinefelter’s syndrome

Rob McLachlan



Most cases of Klinefelter’s syndrome remain undiagnosed and untreated. The key clinical feature of the condition is reduced testicular volume and this should be routinely measured as part of a male physical examination.

Article Extract

Klinefelter’s syndrome is a common genetic condition that affects one in 650 men worldwide; however, up to 70% of cases remain undiagnosed and therefore untreated for life. Klinefelter’s syndrome results from the presence of an extra X chromosome (47XXY) in the genome of the affected patient. Chromosomal mosaicism (the presence of both 47XXY and 46XY cells) occurs in about 10% of men who usually have milder or fewer features of Klinefelter’s syndrome, whereas the presence of additional X chromosomes (e.g. 48XXXY or 49XXXXY) is rare and associated with more severe signs and symptoms.