How can epididymo-orchitis be distinguished from torsion clinically?

• A. Sudden onset with absent cremasteric reflex
• B. High-riding testis without fever
• C. Gradual onset with fever, scrotal swelling, and positive Prehn sign
• D. Nausea and vomiting without fever

Answer: (C)

The key idea is differentiating an inflammatory, gradually developing scrotal condition from an acute torsion crisis. Epididymo-orchitis tends to come on more slowly and is often accompanied by systemic signs like fever and local swelling. A positive Prehn sign—pain relief when the scrotum is elevated—fits this inflammatory process because elevating the scrotum can reduce edema and discomfort associated with epididymal inflammation. In contrast, testicular torsion typically presents with sudden, severe pain and exam findings such as an absent cremasteric reflex and a high-riding, horizontal testis; fever is not a defining feature. So the combination of gradual onset, fever, scrotal swelling, and a positive Prehn sign makes epididymo-orchitis the more likely diagnosis and helps distinguish it clinically from torsion. If uncertainty remains, urgent Doppler ultrasound can assess testicular blood flow to rule out torsion.