It may be due to an injury, infection, or, in rare cases, cancer.
It is often difficult to tell what the underlying cause is until you are examined by a healthcare provider.
The testicles, also called thetestes, are an important part of themale reproductive system.

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Swollen testicles can affect anyone with testicles or testicular implants.
It also describes when swollen testicles are a sign of a medical emergency needing immediate care.
They are situated within a sac of skin beneath the base of thepeniscalled thescrotum.
Together, the testicles and scrotum are commonly referred to as “balls.”
The symptoms of swollen testicles can vary based on the underlying cause.
In some cases, this may be a sign of a serious medical situation.
However, more often than not, it is related to a treatable medical condition.
There are severe common causes of testicular swelling a healthcare provider may explore during an evaluation.
In some cases, an injury may seem mild and only cause symptoms hours later.
At other times, a person may not even realize what caused an injury.
An example of this is testicular swelling that occurs after a bike ride.
Epididymitis
Epididymitisis a painful swelling of the epididymis.
It may also occur due to repetitive friction from a bicycle seat or a saddle.
Epididymitis often occurs alongside the swelling of the testicle itself, calledorchitis.
When both the testicle and epididymis are affected, it is known as epididymo-orchitis.
You may also feel a dull ache or heaviness in the testicle, particularly after physical exertion.
The condition generally is unilateral but can sometimes be bilateral.
Hydrocele usually affects infants but can occur in people of any age.
It can create a visible bulge on the groin and extend into the scrotum, causing unilateral testicular swelling.
While some inguinal hernias cause no pain, the likelihood of pain increases the longer you leave it untreated.
Nausea and vomiting are also common.
Testicular swelling is a central feature.
How to Treat Swollen Testicles
The treatment of swollen testicles varies based on the underlying cause.
If the damage is severe enough, the testicle would need to be removed.
The delayed treatment of any cause of swollen testicles may result in testicular injury, sometimes irreversible.
Are There Tests to Diagnose the Cause of Swollen Testicles?
If there is a nodule, the healthcare provider will want to determine if it has characteristics of cancer.
The testicle may feel firmer than usual.
Chief among these is testicular torsion.
Unless treated in a timely manner, testicular torsion can lead to the loss of a testicle.
If treatment is delayed until 12 to 24 hours, the risk of testicular loss is around 90%.
With that said, testicular torsion can occur at almost any age.
Summary
Swollen testicles can have many different causes, both serious and nonserious.
These include testicle injuries and conditions like epididymitis, varicocele, hydrocele, inguinal hernia, and testicular torsion.
Although testicular cancer is a less likely cause, swollen testicles are one of the defining symptoms.
If the swelling is sudden and accompanied by severe pain, go to your nearest emergency room.
Swollen testicles due to testicular cancer may cause no pain, particularly in the early stages.
Swollen testicles, even when mild, should never be considered normal.
If symptoms do not improve or if they get worse, see a healthcare provider.
Testicular torsion can occur for no apparent reason while sitting, standing, or even sleeping.
Seminoma cancer is a slow-growing form found in males in their 40s and 50s.
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