The epididymis can become inflamed and swell. This hurts. You might feel more swelling on the affected side. This is, again, better done with the standing patient. The testis will have a normal lie and the cremaster reflex is present. Approximately half of patients with epididymitis will also have scrotal edema. Some cases will present with an erythematous scrotum as well. Elevation of the testis may reduce pain – this is known as “Prehn’s sign,” but it isn’t especially sensitive or specific. There can be associated urinary symptoms like dysuria, hesitancy and urgency if the patient has a concomitant UTI or urethritis.

In terms of etiology you should first assess whether the patient is sexually active? This adds chlamydia and gonorrhea to the fray. Otherwise E.coli is the most common bacterial cause. Overall most cases don’t have an easily identifable proximate infectious provocateur. You can tell patients “it’s probably a virus,” but what do we know. There is also an association with mycoplasma, though it is limited to case series. You can make the diagnosis clinically, and obtain an ultrasound if you aren’t 100% sure. Any sexually active male should have testing for STDs (include HIV and syphilis while you’re at it) and either treat empirically or wait on your GC and chlamydial DNA studies. Prepubertal patients should be encouraged to provide a urine sample especially if they have urinary symptoms.

You may be surprised to learn that antibiotics are NOT always indicated. You should treat if:

Pyuria >5 wbc/hpf on a clean catch, positive nitrate and/or leukocyte esterase

Positive urine culture

Underlying UTI risk factors

For prepubertal males with a suspected bacterial cause use trimethoprim/sulfamethoxazole or cephalexin for 10 days. With teenagers, especially if you are considering STDs treat with Ceftriaxone 250mg IM x1 then doxycyline 100mg bid x10 days. Additional beneficial treatments include rest, NSAIDs, and scrotal elevation.