Male hypogonadism with a deficiency of testosterone is a relatively common disorder in clinical practice and has significant effects on the fertility, sexual function, and general health of affected men.
Hypogonadism can occur for a number of reasons, some relatively common and others rare. Certain men have hypogonadism from birth while others may develop this condition later in life. Types of hypogonadism include:
- Primary hypogonadism (testicular failure) – Low serum testosterone levels with gonadotropins (FSH, LH) above the normal range. Klinefelters, surgical removal, bilateral mumps related orchitis, toxic damage by alcohol, heavy metals or chemotherapy.
- Secondary (gonadotropin) hypogonadism – Caused by a pituitary failure or pituitary-hypothalamic injury from tumors, trauma, or radiation; characterized by low serum testosterone levels, but with gonadotropins in the normal or low range
Testicular atrophy may occur as the result of hernia repair, use of anabolic steroids, Klinefelter’s syndrome and normal aging, although relatively little is known about the mechanisms underlying germ cell loss in aging. Sterility from mumps is rare even when both testicles are involved. Some degree of testicular shrinkage may be detectable after the mumps infection; however, it does not cause sterility.
In adult males with low serum testosterone and elevated gonadotropin levels, primary testicular failure should be suspected, whereas low or normal gonadotropin and low testosterone levels suggest a hypothalamic or pituitary disorder.
In men with clinical symptoms of primary or secondary hypogonadism, the deficiency of testosterone can be treated effectively with currently available preparations. Clomid and Arimidex act by reducing the conversion of testosterone to estrogens. HCG is being used to mimic luetinizing hormone to increase testosterone production in athletes and those with testicular atrophy. It must be used carefully and cyclically to prevent side effects.