Extensive Necrotizing Fasciitis Involving the Pararectal Space, Retroperitoneal Space and Abdominal Wall Caused by an Anal Fistula

Necrotizing fasciitis caused by bowel disease is a rare but life-threatening infection. A 46-year-old male schizophrenic was trasferred from a local mental hospital to our hospital with abdominal pain and distention. Clinical examination revealed swelling and redness of the right flank and lower abdominal wall with tenderness, and anal fistula. Laboratory data showed leucocytosis, hypoproteinemia and hyperglycemia. CT scan demonstrated extensive gas and inflammatory exudate in the paravesical space, retroperitoneal space and abdominal wall. A diagnosis of necrotizing fasciitis involving the pararectal space, retroperitoneal space and abdominal wall caused by an anal fistula was made. Urgent aggressive surgery was performed. The retroperitoneal space was opened and drained by the extraperitoneal incision. The affected abdominal wall was incised and necrotic tissue debrided as thoroughly as possible. Systemic administration of antibiotics and gamma-globulin was started after surgery. In addition to the initial surgery, repeated daily irrigation of the retroperitoneal space, perirectal space and abdominal wall was performed under general anesthesia. The patient made a full recovery and was transferred to the mental ward on the 55th day after admission. Early diagnosis, rapid initial aggressive surgery and repeated daily surgery are important to save the patient's life.