Hypogonadism in elderly men above 45 years

Hypogonadism in men is a clinical syndrome that results from failure of the testis to produce physiological levels of testosterone (androgen deficiency) and the normal number of spermatozoa due to disruption of one or more levels of the hypothalamic-pituitary- gonadal (HPG) axis.Abnormalities of the HPG axis at the testicular level cause primary testicular failure, whereas central defects of the hypothalamus or pituitary cause secondary testicular failure.The distinction between primary and secondary hypogonadism is made by measurement of the serum concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH):• The patient has primary hypogonadism if the serum testosterone concentration and the sperm count are below normal and the serum LH and FSH concentrations are above normal.• The patient has secondary hypogonadism if the serum testosterone concentration and the sperm count are subnormal and the serum LH and FSH concentrations are normal or reduced.