Serdar Balcı

Inflammatory Bowell Diseases

Serdar BALCI, MD

Inflammatory bowel disease (IBD)

Chronic condition

Inappropriate mucosal immune activation

Crohn disease

Ulcerative colitis

Robbins Basic Pathology

Robbins Basic Pathology

Robbins Basic Pathology


The cause(s) of IBD remains uncertain

Combination of errant host interactions with intestinal microbiota

Intestinal epithelial dysfunction

Aberrant mucosal immune responses


Mucosal immune responses

In ulcerative colitis significant TH2

Mucosal IL-13 production is increased in ulcerative colitis, Crohn disease

Polymorphisms of the IL-10 gene, IL10 receptor gene, have been linked to ulcerative colitis but not Crohn disease

Epithelial defects


Robbins Basic Pathology

Crohn Disease

Robbins Basic Pathology

Robbins Basic Pathology

Robbins Basic Pathology

Early lesion of the ileum showing hyperemia and focal ulceration

Autopsy Pathology: A Manual and Atlas

Chronic lesion involving the ileum

Sharp demarcation between the normal area on the right and the involved area on the left

Narrowing of the lumen, thickening of the intestinal wall, and coarsely textured (“cobblestone”) mucosa with fissures

Autopsy Pathology: A Manual and Atlas

Extensive transmural disease

Mesenteric fat frequently extends around the serosal surface

creeping fat

Robbins Basic Pathology

Active Crohn disease

Abundant neutrophils infiltrate and damage crypt epithelium

Clusters of neutrophils within a crypt crypt abscess

Crypt destruction

Ulceration is common

Abrupt transition between ulcerated and normal mucosa

Repeated cycles of crypt destruction and regeneration

-distortion of mucosal architecture

-Normally straight and parallel crypts take on bizarre branching shapes and unusual orientations to one another

Robbins Basic Pathology

Crohn disease

Noncaseating granulomas

-Hallmark of Crohn disease

-Found in approximately 35% of cases

-Arise in areas of active disease or uninvolved regions

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Noncaseating granulomas

-In any layer of the intestinal wall

-May be found in mesenteric lymph nodes

-Cutaneous granulomas

–form nodules

–misnomer: metastatic Crohn disease

Robbins Basic Pathology

Robbins Basic Pathology

Robbins Basic Pathology

Robbins Basic Pathology

Ulcerative Colitis

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Robbins Basic Pathology

Disease of the entire colon is termed pancolitis

**Total colectomy with pancolitis showing active disease, with red, granular mucosa in the cecum (left) and smooth, atrophic mucosa distally (right). **

Robbins Basic Pathology

broad-based ulceration of the colonic mucosa of the distal colon


Autopsy Pathology: A Manual and Atlas

Involved colonic mucosa may be slightly red and granular-appearing or exhibit extensive broad-based ulcers

The transition between diseased and uninvolved colon can be abrupt

Sharp demarcation between active ulcerative colitis (bottom) and normal (top)

Robbins Basic Pathology

Histologic features of Ulcerative Colitis

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Ulcerative Colitis

Relapsing disorder

Attacks of bloody diarrhea

Expulsion of stringy, mucoid material

Colectomy cures intestinal disease, but extraintestinal manifestations may persist

Indeterminate Colitis

Histopathologic and clinical overlap between ulcerative colitis and Crohn disease is common

Not possible to make a distinction in up to 10% of patients with IBD

Colitis-Associated Neoplasia

Risk of dysplasia:

Risk increases sharply 8 to 10 years after disease initiation

Pancolitis are at greater risk than those with only left-sided disease.

Greater frequency and severity of active inflammation (characterized by the presence of neutrophils) may increase risk

Patients enrolled in surveillance programs approximately 8 years after diagnosis of IBD

If there is primary sclerosing cholangitis screen at time of diagnosis