Inflammatory bowel disease classification

Inflammatory Bowel Disease Main page
Patient Information
Overview
Causes
Classification Crohn's disease Ulcerative colitis
Differential Diagnosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Inflammatory bowel disease can be classified mainly into Crohn's disease and ulcerative colitis(UC).

Classification

Inflammatory bowel disease can be classified mainly into

• Crohn's disease
• Ulcerative colitis (UC)

Accounting for far fewer cases are other forms of IBD:

• Collagenous colitis
• Lymphocytic colitis
• Ischaemic colitis
• Diversion colitis
• Behçet's syndrome
• Infective colitis
• Indeterminate colitis

The main difference between Crohn's disease and UC is the location and nature of the inflammatory changes. Crohn's can affect any part of the gastrointestinal tract, from mouth to anus (skip lesions), although a majority of the cases start in the terminal ileum. Ulcerative colitis, in contrast, is restricted to the colon and the anus.

Microscopically, ulcerative colitis is restricted to the mucosa (epithelial lining of the gut), while Crohn's disease affects the whole bowel wall.

Finally, Crohn's disease and ulcerative colitis present with extra-intestinal manifestations (such as liver problems, arthritis, skin manifestations and eye problems) in different proportions.

In rare cases, patients have been diagnosed with both Crohn's disease and ulcerative colitis, which is really called Crohn's colitis.