26.  A 16-year-old male presents to the emergency department…

26.  A 16-year-old male presents to the emergency department with sudden onset of severe left testicular pain that began 2 hours ago while at rest. He is nauseated and has vomited once. On physical exam, the left testicle is swollen, elevated, and very tender. The cremasteric reflex is absent on the affected side. What is the most likely diagnosis and best next step in management?