Klinefelter syndrome in the aged.

Three cases of Klinefelter syndrome diagnosed late in life are reported with the clinical and post-mortem findings. The diagnosis was suspected owing to the absence of testes and the presence of associated varied clinical features. The urinary follicle-stimulating hormone levels were not elevated and were very low in two of the cases. Bronchopneumonia, ascending pyelonephritis and cystitis were the main causes of death but there were varied pathological findings in the prostate of benign hyperplasia, carcinoma and prepubertal gland. Marked atherosclerosis of the aorta and the lower-limb vessels were present but the coronary systems were little affected. It is suggested that, because of the presence of two X chromosomes and the absence of testes, this condition may give a female pattern of longevity, many examples being overlooked in old age on account of inadequate clinical examination. Some support for this hypothesis will be found if its incidence in the aged is shown to be greater than in the young.