FALSE statement about Ulcerative colitis is
**Core Concept**
Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) characterized by chronic inflammation and ulceration of the colonic mucosa. The exact pathogenesis of UC involves a complex interplay between genetic predisposition, environmental factors, and an abnormal immune response to luminal antigens.
**Why the Correct Answer is Right**
The correct answer is related to the characteristic features of UC. Ulcerative colitis typically starts in the rectum and extends proximally in a continuous manner, involving the entire colon in pancolitis. The inflammation in UC is usually superficial and limited to the mucosa and submucosa, whereas in Crohn's disease, the inflammation can be transmural, affecting the entire thickness of the bowel wall.
**Why Each Wrong Option is Incorrect**
* **Option A:** This statement is incorrect because UC is not typically associated with strictures or fistulas, which are more common in Crohn's disease.
* **Option B:** This statement is incorrect because UC is characterized by a continuous pattern of involvement, starting in the rectum and extending proximally, whereas Crohn's disease can have skip lesions.
* **Option C:** This statement is incorrect because UC is not typically associated with an increased risk of colorectal cancer in the absence of dysplasia or long-standing disease.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the risk of colorectal cancer in UC increases with the duration of disease, particularly in patients with extensive colitis or a family history of colorectal cancer.
**Correct Answer: B. Ulcerative colitis typically starts in the rectum and extends proximally in a continuous manner, involving the entire colon in pancolitis.**