A rare case of infectious colitis.

Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for numerous infectious processes. Gastrointestinal tract involvement is rather rare and only a handful of cases of MRSA colitis have been reported in North America. We present a case of MRSA colitis in an adult without apparent risk factors. Abdominal computed tomography (CT) showed thickening of the sigmoid colon, indicative of colitis, and empiric therapy with ciprofloxacin and metronidazole was started. Initial work-up for infection-including blood and stool cultures, and stool Clostridium difficile toxin assay-was negative. The patient's clinical status improved but his diarrhea did not abate. Repetition of stool culture demonstrated luxuriant growth of MRSA sensitive to vancomycin. Oral vancomycin was administered and the patient's symptoms promptly ceased.