Imaging quiz: Fever of undetermined origin in a soldier

An athletic 26-year-old black male soldier presented with a 5-week history of intermittent fever up to a maximum of 102 degrees F (38.9 degrees C), 10-lb weight loss, and malaise. He denied any localizing signs or symptoms. At the time of admission his medical, surgical, and travel histories were unremarkable; and the physical exam, including his temperature, was within normal limits. His only medication was occasional use of acetaminophen, and his only lab abnormalities were a blood urea nitrogen of 58 mg/dL and serum creatinine of 3.4 mg/dL.