What is the primary symptom of epididymitis?

The primary symptom of epididymitis is testicular swelling. This condition is an inflammation of the epididymis, which is a structure located at the back of the testicle that stores and matures sperm. When the epididymis becomes inflamed, it often presents with noticeable swelling in the testicular area. Patients may also experience tenderness and pain in the affected testicle, which can be accompanied by other symptoms such as erythema or warmth in the region.

While severe abdominal pain, urinary retention, and groin pain can occur in various urological conditions, they are not the hallmark symptoms of epididymitis. Severe abdominal pain is more associated with conditions like appendicitis or abdominal emergencies. Urinary retention typically suggests a problem with the bladder or urethra rather than isolated epididymitis. Groin pain can result from various issues, including musculoskeletal problems or hernias, but it does not specifically indicate epididymitis. Thus, testicular swelling stands out as the primary and most indicative symptom of this condition.