Ulcerative Colitis (UC)
Ulcerative Colitis is a chronic inflammatory condition characterized by continuous mucosal and submucosal inflammation of the colon, typically beginning in the rectum.
1. Pathological Hallmarks
| Finding | Description |
|---|---|
| Continuous Involvement | Starts at the rectum and extends proximally; no “skip” lesions. |
| Crypt Abscesses | Neutrophils invade the crypts (a hallmark histological feature). |
| Pseudopolyps | Regenerating islands of mucosa surrounded by ulceration. |
| “Lead Pipe” Colon | Chronic disease causes loss of haustra due to muscular atrophy. |
2. Exam Must-Knows
- Primary Sclerosing Cholangitis (PSC): Strong association with UC; patients present with elevated alkaline phosphatase and often have p-ANCA positivity.
- Toxic Megacolon: A life-threatening complication of severe UC; monitor for signs of systemic toxicity and dilated colon on imaging.
- Cancer Risk: Long-standing UC significantly increases the risk of colorectal carcinoma. Annual surveillance colonoscopy is required after 8–10 years of disease.
Pathology Board Hint: For board exams, distinguish UC from Crohn’s by looking for continuous rectal involvement and the absence of granulomas. If a patient with UC develops jaundice or elevated liver enzymes, think PSC.