Review Question - QID 212800

A 16-year-old teenage boy is brought to the emergency room for severe left groin pain. He reports feeling feverish this morning but insisted on going to his basketball practice this afternoon. Shortly after the practice, he began experiencing severe pain at his left groin that is described as sharp and burning in quality. The pain does not radiate anywhere. He denies chest pain, shortness of breath, abdominal pain, hematuria, or abnormal discharge, but endorses fever and chills. He is sexually active with his girlfriend and reports consistent condom use. Per his mom, last week he had “a weird flu episode” where his left cheek was swollen but resolved within 4 days. He did not seek medical attention as his mother preferred natural/holistic management; the patient is not vaccinated. A physical examination demonstrates a relatively healthy patient in acute distress and an erythematous, swollen left scrotum. A Doppler ultrasound of the testicles is obtained and shown in Figure A. What is the most likely explanation for this patient’s presentation?