Testicular atrophy

Testicular atrophy, or shrinking of the testicles, can be due to a variety of causes, including:

• Normal aging
• Exposure to radiation or certain chemicals
• Injury to the testicles
• Certain medications, such as female hormones, some corticosteroid medications and some chemotherapy drugs
• Viral infections such as mumps or HIV
• Interruption of blood supply to the testicles due to surgery or disease
• Varicose veins in the scrotum (varicocele)

The testicles consist primarily of germ cells, which make sperm, and Leydig cells, which make male sex hormone (testosterone). Testicular atrophy can affect either or both of these tissues. If only germ cells are affected, infertility may result. If Leydig cells are affected, testosterone levels will diminish, causing decreased sex drive, loss of muscle and bone mass, hot flashes, weight gain, and mood swings.

A doctor may make a diagnosis of testicular atrophy by:

• Physical examination
• Semen analysis
• Blood tests to measure hormone levels

Treatment of testicular atrophy is directed at the underlying cause when possible. Occasionally, atrophy can be reversed if diagnosed and treated early, but it is usually a permanent condition.