Abstract
BACKGROUND: Polyarteritis nodosa (PAN) is a primary systemic necrotizing vasculitis with diffuse organ involvements, resulting in a high mortality rate due to multiple organ failure. Although the small bowel is the frequently targeted organ of PAN-associated vasculitis, rectal involvement is very rare, and only one case of rectal bleeding has been previously reported. The mortality rate of PAN with gastrointestinal (GI) perforation is reportedly much higher than that of without severe GI involvement. We herein report the first case of rectal perforation due to PAN, successfully managed with an adequate surgical intervention. CASE PRESENTATION: A 66-year-old woman with PAN had abdominal pain and melena with guarding. Computed tomography scan showed abdominal free air and bubbles in the rectal hematoma. We diagnosed it acute peritonitis, and emergency surgery was performed. After removing rectal hematoma and necrotic tissue, a huge lack of rectal wall spreading to the pelvirectal space was observed. In order to totally remove the necrotic tissue, abdominoperineal resection was needed. Together with histopathological examinations which showed neutrophils and fibrinous necrosis, we finally diagnosed rectal perforation due to PAN. At 19-month follow-up after surgery, she was still healthy with a stable disease of PAN. CONCLUSIONS: We herein reported the first case of successfully managed rectal perforation due to PAN. Early adequate surgical resection may be important for the case with rectal perforation.