Elderly woman with acute abdominal pain

A 67-year-old woman complains of acute diarrhea and severe abdominal pain. She was recently treated with broad-spectrum antibiotics for community-acquired pneumonia. A CBC shows an elevated WBC count. The patient subsequently develops septic shock and dies. Examination of the rectosigmoid region of colon at autopsy reveals raised, yellowish plaques that adhere to the underlying mucosa. These findings are typical of which of the following gastrointestinal diseases?

The correct answer is B. Pseudomembranous colitis. There were a total of 15 responses. A breakdown of responses are inside the parentheses below.

The most likely diagnosis is:

A. Ulcerative colitis (0)
B. Pseudomembranous colitis (15)
C. Crohn disease (0)
D. Colonic adenocarcinoma (0)
E. Peptic ulcer disease (0)

(see results graphically)