CASE
The patient was a 71-year-old female with diarrhea containing mucus and pink-red streaks 3 to 5 times daily for the past week. She reported abdominal cramping, chills, and nausea but no fever or emesis. Bowel movements were small, about 1 tablespoon in quantity. Early satiety had caused a weight loss of 6 to 8 lb in a week's time.
The patient's history included stage IV metastatic melanoma (involving the scalp, lung, hilar nodes, and liver) that had progressed despite an adoptive cell transfer. She was being treated with the CTL-associated antigen 4 (CTLA-4) blocker ipilimumab (Yervoy). Her history also included coronary artery disease, MI, hypercholesterolemia, type 2 diabetes, stroke, cholecystectomy, depression, and tonsillectomy. The patient took lisinopril, citalopram, baby aspirin, metformin, atenolol, multivitamins, and amlodipine daily.
She denied drinking alcohol, smoking, and any recent travels or exposures. On examination, the patient was in no acute distress. Vital signs were stable. Lungs were clear to auscultation bilaterally. The abdomen was soft and nondistended with positive bowel sounds in all four quadrants. Slight tenderness was present in the suprapubic area. No guarding, rebound tenderness, palpable masses, or splenomegaly was present. Stool was brown and positive for guaiac. Results of a CBC with differential and chemistries were normal. Stool cultures for Clostridium difficile and fecal leukocytes were negative. The patient underwent flexible sigmoidoscopy (Figure 1).
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