American Board of Internal Medicine (ABIM) Certification Practice Exam

Which of the following is NOT a cause of inflammatory diarrhea?

1. Celiac disease

2. Clostridium difficile infection

3. Ischemia

4. Cholera infection

The correct answer is: Cholera infection

Inflammatory diarrhea is typically characterized by the presence of blood, mucus, and leukocytes in the stool due to inflammation of the intestinal mucosa. It is important to understand the underlying mechanisms of different conditions that can cause diarrhea. Celiac disease, an autoimmune disorder triggered by gluten intake, leads to inflammation in the small intestine, resulting in malabsorption and diarrhea. Clostridium difficile infection is a bacterial infection known for causing significant inflammation in the colon, leading to severe diarrhea that may contain blood and often accompanied by abdominal pain. Similarly, ischemia refers to reduced blood flow to the bowel, which can cause inflammation and subsequent diarrhea, particularly in cases where bowel tissue is compromised. Cholera, on the other hand, is caused by the bacterium Vibrio cholerae, which does not lead to inflammation of the intestinal mucosa. Instead, it results in secretory diarrhea due to the release of enterotoxins that stimulate excessive secretion of water and electrolytes into the intestinal lumen, causing watery diarrhea without the accompanying inflammatory changes seen in the other conditions mentioned. Therefore, since cholera does not cause inflammation in the bowel, it is identified as not being a cause of inflammatory diarrhea.