A 76-year-old man with diabetes and a 2-year history of mediastinal lymphadenopathy of unknown cause presented with fever and fatigue. Pyuria was seen on urinalysis. Contrast-enhanced computed tomography (CT) was obtained (images A-C) and urinary acid-fast staining (image D) was performed.

He was treated with a beta-lactam antibiotic, but pyuria and fever persisted. The results of a urine culture were negative. *This case is from Docplexus editorial team for educative purpose only Source: NEJM Stay connected, the answers will be posted in next 48h!