Rosai Chapter 17 - Large Bowel Flashcards
The large bowel comprises the
terminal 1 to 1.5 m of the GIT
Flexure
-junction of Ascending and Transverse colon
Hepatic
Flexure
-junction of Transverse and Descending colon
Splenic
Rectum forms
distal 8 to 15 cm of extraperitoneal large bowel
Paneth cells are normally present only in the (2):
- Cecum
- Proximal right colon
POSITIVE or NEGATIVE
IHC of epithelial cells of the normal colonic mucosa:
CK8
POSITIVE
POSITIVE or NEGATIVE
IHC of epithelial cells of the normal colonic mucosa:
CK18
POSITIVE
POSITIVE or NEGATIVE
IHC of epithelial cells of the normal colonic mucosa:
CK19
POSITIVE
POSITIVE or NEGATIVE
IHC of epithelial cells of the normal colonic mucosa:
CK20
POSITIVE
POSITIVE or NEGATIVE
IHC of epithelial cells of the normal colonic mucosa:
CK7
NEGATIVE
Most important complications of Hirschsprung disease (2)
- Acute intestinal obstruction
- Enterocolitis
Microscopic hallmark of Hirschsprung disease
-absence of ganglion cells (aganglionosis) in BOTH plexuses of a segment of bowel
Standard guideline in which biopsy should be taken for Hirschsprung disease in INFANTS
2cm above the anal valve
Standard guideline in which biopsy should be taken for Hirschsprung disease in OLDER CHILDREN
3cm above the anal valve
IHC characteristic of Hirschsprung disease
Loss of Calretinin-immunoreactive nerves
For frozen section evaluation of Hirschsprung disease to be reliable, the tissue should be:
at least 4 mm long
other name of intestinal neuronal dysplasia (2):
- Neuronal colonic dysplasia
- Hyperganglionosis
Main complications of Diverticulosis (3):
- Hemorrhage
- Perforation
- Diverticulitis
Risk factors in the development of carcinoma in patients with ulcerative colitis (4):
- Patients with extensive colitis
- those with disease for greater than 7-10 years
- young age of colitis onset
- Primary sclerosing cholangitis
Earliest gross change in patients with ulcerative colitis who develop carcinoma
-thick mucosa with a finely nodular or velvety surface configuration
Two important diagnostic feature of Crohn disease in the colon
- Grossly, segmental distribution (with “skip” areas that can be demonstrated radiographically)
- Preference for the right side of the colon
Typical triad of colonic Crohn disease
- Fissures
- Noncaseating sarcoid-like granulomas
- Transmural involvement
The main features of large bowel Crohn disease to look for in an endoscopic biopsy (5):
- Patchy mucosal inflammation
- Granulomas
- Preservation of the Goblet cell population
- Pyloric gland metaplasia
- Maintenance of the architecture of the glands
Classic site of involvement of Arteriosclerosis which could lead to ischemic colitis
Splenic flexure
other name of Acute infectious-type colitis
Acute self-limited colitis
Ulcerative colitis vs. Infectious-etiology
-Crypt distortion and plasma cell infiltration in the basal portion of the mucosa
-Ulcerative colitis
Ulcerative colitis vs. Infectious-etiology
-Acute inflammation out of proportion to chronic features
-Infectious-etiology
Main microscopic abnormalities of Allergic colitis and proctitis on rectal biopsy (2):
- Mucosal edema
- Marked eosinophilic infiltration
Lymphocytic colitis vs. Collagenous colitis
Main microscopic differences:
-absence of a thickened collagenous layer
Lymphocytic colitis
Lymphocytic colitis vs. Collagenous colitis
Main microscopic differences:
-greater prominence of intraepithelial lymphocytes
Lymphocytic colitis
Most common changes of Diversion colitis microscopically (3):
- Mild to moderate lamina propria expansion, predominantly by plasma cells
- Crypt abscesses
- Follicular lymphoid hyperplasia (most common and prominent)
Feature favoring TUBERCULOSIS vs. CROHN DISEASE
-Caseation and coalescence of the granuloma
-Tuberculosis
Feature favoring TUBERCULOSIS vs. CROHN DISEASE
-Longitudinal ulcers
-Crohn disease
Feature favoring MYCOPHENOLATE-INDUCED INJURY vs. GVHD
-lack of endocrine aggregates in the lamina propria
Mycophenolate-induced injury