Acute epididymitis is the acute inflammation of the epididymis. It's one of the most common cause of acute scrotum. Symptoms include unilateral scrotal pain and swelling, usually of gradual onset.

50% of acute epididymis cases also include inflammation of the testicles, called epididymo-orchitis.

Etiology

Acute epididymitis is most commonly due to a sexually transmitted infection like Neisseria gonorrhoeae and Chlamydia trachomatis. It may also be secondary to a lower urinary tract infection.

Diagnosis and evaluation

The diagnosis is clinical, when other causes of acute scrotum (like torsion and Fournier gangrene) are ruled out. The Prehn sign is positive, meaning that the pain is reduced when the scrotum is elevated. There may be concurrent symptoms of UTI or STI. The cremaster reflex is intact (as opposed to testicular torsion). Inflammatory markers may be elevated.

Urine dipstick test may show evidence of UTI, and PCR may be positive for STI pathogens.

Management

The choice of empiric antibiotics depends on whether the epididymitis is presumed to be secondary to UTI or STI. If presumed due to UTI, sulfamethoxazole and trimethoprim can be a first choice, and if presumed due to STI, doxycycline can be a first choice.

Elevation of the painful testicle and analgesics are indicated for supportive therapy.