Numerous issues can cause the swelling of the testicles. Epididymitis involves the swelling of the epididymis, the part on the rear of the testicle where sperm is stored. This swelling is caused by either the growth of a cyst or an infection. Cysts can be harmless and usually resolve on their own. If there is no pain associated with the cyst, the condition is not usually treated. Bacterial epididymitis usually stems from a urinary tract infection or a sexually transmitted disease. If the cause is bacterial, an antibiotic is required to resolve the infection and swelling.
Hydrocele and Orchitis
Hydrocele is defined as an accumulation of fluid in the scrotal sack. The most common symptoms include a swollen testicle that appears like a water balloon. Hydrocele is common in newborns and then again in older men. Most often, hydrocele is caused by traumatic injury or radiation therapy. Although hydrocele does not cause pain and is not a dangerous condition, surgery is often required if the condition does not resolve on its own.
The swelling associated with orchitis is most often caused by the mumps. It is a very painful condition where, besides swollen testicles, symptoms include the ejaculation of blood and blood in the urine. Orchitis can also be associated with epididymitis, where the infection spreads from the epididymis to the testicle itself. Antibiotics are necessary to clear up the infection.
Cancer and Varicocele
According to the American Cancer Society, testicular cancer is fairly uncommon; however, a tumour may cause the testicles to swell.
Another cause of testicular swelling, varicocele, occurs when a vein on the testicle becomes swollen. This condition can prevent the proper blood from reaching the testicle when the vein swells, causing that blood to become backed up. If not properly treated, this backed-up blood can raise the average temperature of the scrotal sack and make for a lower sperm count. Often, men with varicocele will need to wear a jock strap to cut down on the pain associated with the condition. If the problem persists, surgery is often necessary to cut and tie off the abnormal vein.