While a slight size difference between testicles is often normal, a sudden and noticeable change, especially if your left testicle unexpectedly appears larger than your right, warrants prompt medical evaluation.
Normal Testicle Size Variation vs. Sudden Change
It's common and normal for guys to have one testicle a bit bigger than the other. This isn't usually a cause for concern if it's a long-standing, minor difference. A typical size variation might be about the size of half a teaspoon. Interestingly, usually the right testicle is larger than the left. If you've always had one testicle slightly larger than the other, and it's a minor difference, you can discuss it with your doctor at your next routine checkup.
However, the key word in your question is "suddenly." A sudden increase in the size of one testicle, particularly if it's accompanied by pain or other symptoms, is not considered a normal variation and requires immediate medical attention. It suggests an underlying condition that needs to be diagnosed and treated promptly.
Potential Causes of Sudden Testicular Enlargement
When a testicle suddenly becomes larger, especially the left one, it could be due to various conditions. These often involve fluid accumulation, inflammation, or other issues within the scrotum. Here are some potential causes:
- Epididymitis: This is an inflammation of the epididymis, a coiled tube at the back of the testicle that stores and carries sperm. It's often caused by a bacterial infection (including sexually transmitted infections - STIs) or, less commonly, a virus.
- Symptoms: Pain (mild to severe), swelling, redness or warmth of the scrotum, fever, painful urination, discharge from the penis.
- Orchitis: Inflammation of the testicle itself, often caused by a viral infection (like mumps) or a bacterial infection.
- Symptoms: Swelling, pain, tenderness, fever, nausea, fatigue. Often occurs alongside epididymitis (epididymo-orchitis).
- Hydrocele: A collection of fluid around the testicle, causing swelling. It's usually painless and can develop suddenly or gradually.
- Symptoms: Painless swelling in one or both testicles, feeling of heaviness. While often gradual, it can become noticeable quickly.
- Varicocele: An enlargement of the veins within the scrotum, similar to varicose veins in the legs. Varicoceles usually affect the left testicle due to anatomical differences in the veins. They are often described as feeling like a "bag of worms."
- Symptoms: Often no symptoms, but can cause a dull ache or heavy feeling, especially after standing for long periods. Swelling may be more noticeable when standing and might suddenly become more apparent.
- Testicular Torsion: This is a medical emergency where the testicle twists on its spermatic cord, cutting off blood supply. It causes sudden, severe pain and swelling.
- Symptoms: Sudden, severe pain in the testicle, rapid swelling, abdominal pain, nausea, vomiting, a testicle that appears higher or at an unusual angle. Requires immediate medical attention.
- Testicular Tumor (Cancer): While usually painless and gradual, some testicular cancers can present with a sudden increase in size or a noticeable lump.
- Symptoms: A lump or enlargement in either testicle (often painless), a feeling of heaviness in the scrotum, dull ache in the abdomen or groin, sudden collection of fluid in the scrotum.
To help differentiate between potential causes, here's a quick overview:
| Condition | Key Characteristics | Common Symptoms | Urgency |
|---|---|---|---|
| Epididymitis | Inflammation of the epididymis, often bacterial. | Pain, swelling, fever, painful urination. | Urgent |
| Orchitis | Inflammation of the testicle, often viral or bacterial. | Swelling, pain, tenderness, fever, nausea. | Urgent |
| Hydrocele | Fluid buildup around the testicle. | Painless swelling, feeling of heaviness. | Non-urgent |
| Varicocele | Enlarged veins in the scrotum (more common on left). | Often asymptomatic; dull ache, "bag of worms" feel, worse with standing. | Non-urgent |
| Testicular Torsion | Testicle twists, cutting off blood supply. Medical emergency. | Sudden, severe pain; rapid swelling; nausea/vomiting; testicle repositioning. | Immediate |
| Testicular Tumor | Abnormal growth in the testicle. | Painless lump/enlargement; heavy feeling; dull ache; fluid buildup. | Urgent |
Disclaimer: This table provides general information and is not a substitute for professional medical advice.
When to Seek Medical Attention
Given that your testicle has suddenly become larger, it is crucial to seek immediate medical attention. This isn't a situation to wait for your "next checkup." Conditions like testicular torsion require emergency treatment to save the testicle. Even less urgent conditions like epididymitis or testicular tumors benefit from prompt diagnosis and treatment.
Do not delay seeking medical advice if you experience:
- Sudden, severe pain in the scrotum.
- Rapid swelling of a testicle.
- Fever, nausea, or vomiting along with testicular pain/swelling.
- Any unexplained lump or change in the testicle's size or texture.
A healthcare professional will be able to perform an examination, potentially order imaging tests (like an ultrasound), and accurately diagnose the cause of the sudden enlargement.
What to Expect at a Doctor's Visit
When you visit a doctor for a sudden change in testicle size, they will likely:
- Ask about your symptoms: Including when the swelling started, if you have pain, fever, or any other associated symptoms.
- Perform a physical exam: This will involve examining your scrotum, testicles, and abdomen.
- Recommend diagnostic tests:
- Urinalysis: To check for urinary tract infections or STIs.
- Blood tests: To check for signs of infection or tumor markers.
- Scrotal Ultrasound: This is a common and highly effective imaging test to visualize the testicles and surrounding structures, helping to identify fluid collections, inflammation, blood flow issues (like torsion), or masses.
Based on the findings, your doctor will provide a diagnosis and recommend the appropriate treatment plan.
