Perinephric abscess secondary to a staghorn calculus presenting as a subcutaneous abscess

Perinephric abscesses often present with flank pain and signs of sepsis, and are known to discharge to the skin. We report a case of a young patient presenting with a 48-hour history of painful swelling in her right renal angle following a urinary tract infection and no overt signs or symptoms of sepsis. Plain abdominal films showed a perinephric abscess secondary to a staghorn calculus in the upper pole of the right kidney. On incision and drainage, 700 mL of pus was drained freely. The patient recovered well but required partial nephrectomy. Subcutaneous abscess as a result of intra-abdominal pathology is a recognized but rare complication. This case illustrates that subcutaneous abscesses may have underlying intra-abdominal pathology without overt signs of sepsis.