Acute abdomen as the first presentation of pseudomembranous colitis.

Acute abdomen was the presenting manifestation of pseudomembranous colitis in six men who had previously been treated with antibiotics and presented with abdominal distention, pain, fever, and leukocytosis with absent or mild diarrhea. Plain abdominal radiographs revealed megacolon in two, combined small and large bowel dilation in three, with one of them showing volvuluslike pattern, and isolated small bowel ileus in one. Emergency colonoscopy was performed successfully in all patients and revealed pseudomembranes in five and nonspecific colitis in one. All patients had positive latex test results for Clostridium difficile, and two tested positive for cytotoxicity. All patients were treated with IV metronidazole, resulting in resolution of symptoms and abdominal findings. In addition, two patients underwent colonoscopic decompression with improvement. Endoscopically, complete resolution of the pseudomembranes occurred at 4 weeks in all cases. No patient had a recurrence. It is concluded that (a) pseudomembranous colitis may present as abdominal distention mimicking small bowel ileus. Ogilvie's syndrome, volvulus, or ischemia; (b) in such cases, emergency colonoscopy is safe and useful for diagnosis and therapeutic decompression and may obviate the need for surgery; and (c) treatment with IV metronidazole is effective. Colitis due to C. difficile should be considered in the differential diagnosis of acute abdomen in patients previously treated with antibiotics.