## **Core Concept**
Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) characterized by chronic inflammation and ulceration of the colonic mucosa. Colectomy, or surgical removal of the colon, is a treatment option for UC, particularly in cases of severe disease, dysplasia, or cancer. The question pertains to the extraintestinal manifestations and symptoms of UC that may or may not resolve after colectomy.

## **Why the Correct Answer is Right**
The correct answer, , refers to primary sclerosing cholangitis (PSC). PSC is a chronic liver disease characterized by inflammation and fibrosis of the bile ducts, often associated with IBD, particularly UC. Unlike some extraintestinal manifestations of UC that may improve or resolve after colectomy (e.g., arthritis, skin rashes), PSC is known to continue progressing independently of the colonic disease activity. This is because the pathophysiology of PSC involves immune-mediated damage to the bile ducts, which is not directly linked to the activity of UC in the colon.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Arthritis. Many patients with UC experience peripheral arthritis, which often parallels the activity of the bowel disease and can improve or resolve after colectomy.
- **Option B:** Erythema nodosum. This skin condition is an extraintestinal manifestation of UC that can resolve with treatment of the bowel disease, including colectomy.
- **Option D:** Uveitis. Like arthritis and erythema nodosum, uveitis is an extraintestinal manifestation that can be influenced by the activity of UC and may improve with colectomy.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that while colectomy can significantly improve or resolve many extraintestinal manifestations of UC, it does not affect the course of PSC. Patients with UC and PSC require ongoing monitoring for progression of liver disease, even after colectomy.

## **Correct Answer: C. Primary sclerosing cholangitis.**