A 19 yo M presents to the ED with 1 week of constant, worsening L testicular pain and swelling. He denies urinary symptoms, penile discharge, nausea or vomiting. His VS are remarkable for a temp of 99.1 and HR 110. Physical exam reveals tenderness, swelling and erythema of the L scrotum with normal lie and normal cremasteric reflex b/l. Urine is positive for > 180 wbc. A scrotal ultrasound is obtained. What's the diagnosis? (scroll down for answer)

Inflammation of the epididymis: coiled tube at back of testicle

• Infection stem from uretheral spreading: STI vs bladder pathogens
• Risk factors: STI, prostatitis/UTI, instrumentation, neurogenic bladder, BPH
• On physical exam, testes have normal position and intact cremasteric reflex
• Only 10% of patients with STI related epididymitis present with symptoms of urethritis on exam
• On US the inflamed epididymis will appear enlarged and hyperechoic

Germann, CA and Holmes, JA. Rosen's Emergency Medicine: Concepts and Clinical Practice, Chapter 89, 1209-1231.e2