Bypass enteritis. A new complication of jejunoileal bypass for obesity.

Four patients who had jejunoileal bypass for morbid obesity had increased frequency of diarrhea, diffuse abdominal tenderness and distention, and fever to 104 degrees F. Roentgenographic studies disclosed multiple distended loops in the bypassed bowel with few air fluid levels. Two of these patients underwent operation for suspected peritonitis from abscess or obstruction. No abscess or mechanical obstruction was found. The bypassed bowel contained many subserosal gas-filled blebs. The remaining two patients were treated with antibiotics and showed prompt improvement. "Bypass enteritis" must be considered in the postoperative period in patients undergoing surgery for morbid obesity. It responds to antibiotics and appropriate electrolyte therapy. The presumed factor is overgrowth of enteric bacteria in the distal portion of the bypassed bowel. Accurate diagnosis will obviate the need for surgical exploration to exclude peritonitis.