Retroperitoneal perforation of the appendix presenting as right thigh abscess

A case of retroperitoneal perforation of the appendix presenting with a thigh abscess is described. The patient presented with pyrexia (38 degrees C) and abdominal and right thigh pain. There was tenderness in the right loin. His white blood cell count was 22 x 10(9)/L. An intravenous urogram revealed tapering of the right ureter at the L2/L3 level and suggested an infected obstructive uropathy. The patient failed to respond to drainage and antibiotics, so we performed a computed tomography scan, which showed a retroperitoneal abscess extending to the gluteal region and thigh, with signs of small bowel obstruction. This precipitated surgery. The route of extension of infection was through the sacrosciatic notch, which is considered to be a rare way of spread. The patient made a slow but eventual recovery. The overall mortality of this condition is high, but early recognition of an abdominal source of sepsis with appropriate treatment can improve survival.