A 30 year old man comes in with fevers, chills, malaise, and myalgias. He has no significant past medical or surgical history. He takes no medications. He has no allergies. On review of systems, he notes dysuria, perineal pain, and cloudy urine. He also has urinary dribbling and hesitation. He initially thought this was a urinary tract infection and took a 2 week course of amoxicillin-clavulanate (Augmentin) but his symptoms persisted. He is an avid bike rider and has been training for 8-hours a day. He is not currently sexually active. He denies smoking, but drinks a beer occasionally and smokes marijuana occasionally.
If a biopsy were taken, the image above might be found.
Challenge: If this is more than a UTI, what is it?
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