**Question:** A 40-year-old male presents with chronic diarrhoea for one year. On investigation, the findings obtained were crypt abscess, crypt atrophy, cryptitis and mucositis. Most likely diagnosis is -

A. Crohn's Disease
B. Colitis Ulcerosa
C. Colitis Ischemic
D. Colitis Parasiticus

**Core Concept:** Chronic diarrhoea, crypt abscess, crypt atrophy, cryptitis, and mucositis are characteristic histopathological features associated with inflammatory bowel diseases. Inflammatory bowel diseases (IBD) are a group of conditions characterised by chronic inflammation of the gastrointestinal tract. Crohn's Disease (CD) and Colitis Ulcerosa (UC) are the two primary types of IBD.

**Why the Correct Answer is Right:** The correct answer, Crohn's Disease (CD), is a type of IBD that can affect any part of the gastrointestinal tract from the mouth to the anus. The presence of crypt abscess, crypt atrophy, cryptitis, and mucositis in the patient's histopathological examination supports the diagnosis of CD, as these features are not commonly seen in the other options.

**Why Each Wrong Option is Incorrect:**

A. Colitis Ulcerosa (UC) typically involves the colon and rectum with superficial inflammation, sparing the crypts. The presence of crypt abscess, crypt atrophy, cryptitis, and mucositis in the patient's histopathological examination does not support UC as the diagnosis, as these features are associated with CD.

B. Colitis Ischemic is a type of inflammatory bowel disease caused by hypoperfusion, leading to mucosal necrosis and ulceration. The absence of crypt abscess, crypt atrophy, cryptitis, and mucositis in the patient's histopathological examination does not support ischemic colitis as the diagnosis, as these features are not present in ischemic colitis.

C. Colitis Parasiticus is a condition caused by parasitic infections. The absence of crypt abscess, crypt atrophy, cryptitis, and mucositis in the patient's histopathological examination does not support colitis parasiticus as the diagnosis, as these features are not present in parasitic colitis.

**Clinical Pearl:** In clinical practice, it is essential to consider the differential diagnosis of IBD and ischemic colitis when assessing a patient with chronic diarrhoea and histopathological examination showing crypt abscess, crypt atrophy, cryptitis, and mucositis. A thorough clinical evaluation, including the patient's history, examination, and investigations, is crucial to differentiate between IBD and ischemic colitis.

**Correct Answer Explanation:**

The correct answer is Crohn's Disease (CD). CD is a type of inflammatory bowel disease (IBD) that can affect any part of the gastrointestinal tract, not just the colon. The presence of crypt abscess, crypt atrophy, cryptitis, and mucositis in the patient's histopathological examination supports the diagnosis of CD, as these features are characteristic of CD but not found in ischemic colitis or parasitic