Difference between revisions of "Colon"

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*Gomori trichrome - examine connective tissue.
*Gomori trichrome - examine connective tissue.
*CD117 - to look for the ''interstitial cells of Cajal''.
*CD117 - to look for the ''interstitial cells of Cajal''.
**<50% the expected = abnormal.<ref name=pmid19360428/>
***Normal numbers not defined.
*HU - neuronal marker.<ref name=pmid8586967>{{cite journal |author=Barami K, Iversen K, Furneaux H, Goldman SA |title=Hu protein as an early marker of neuronal phenotypic differentiation by subependymal zone cells of the adult songbird forebrain |journal=J. Neurobiol. |volume=28 |issue=1 |pages=82–101 |year=1995 |month=September |pmid=8586967 |doi=10.1002/neu.480280108 |url=}}</ref>
*HU - neuronal marker.<ref name=pmid8586967>{{cite journal |author=Barami K, Iversen K, Furneaux H, Goldman SA |title=Hu protein as an early marker of neuronal phenotypic differentiation by subependymal zone cells of the adult songbird forebrain |journal=J. Neurobiol. |volume=28 |issue=1 |pages=82–101 |year=1995 |month=September |pmid=8586967 |doi=10.1002/neu.480280108 |url=}}</ref>


Line 944: Line 946:
*A long list of things to report is contained the recommendation of a working group.<ref name=pmid19360428>{{Cite journal  | last1 = Knowles | first1 = CH. | last2 = De Giorgio | first2 = R. | last3 = Kapur | first3 = RP. | last4 = Bruder | first4 = E. | last5 = Farrugia | first5 = G. | last6 = Geboes | first6 = K. | last7 = Gershon | first7 = MD. | last8 = Hutson | first8 = J. | last9 = Lindberg | first9 = G. | title = Gastrointestinal neuromuscular pathology: guidelines for histological techniques and reporting on behalf of the Gastro 2009 International Working Group. | journal = Acta Neuropathol | volume = 118 | issue = 2 | pages = 271-301 | month = Aug | year = 2009 | doi = 10.1007/s00401-009-0527-y | PMID = 19360428 }}</ref>
*A long list of things to report is contained the recommendation of a working group.<ref name=pmid19360428>{{Cite journal  | last1 = Knowles | first1 = CH. | last2 = De Giorgio | first2 = R. | last3 = Kapur | first3 = RP. | last4 = Bruder | first4 = E. | last5 = Farrugia | first5 = G. | last6 = Geboes | first6 = K. | last7 = Gershon | first7 = MD. | last8 = Hutson | first8 = J. | last9 = Lindberg | first9 = G. | title = Gastrointestinal neuromuscular pathology: guidelines for histological techniques and reporting on behalf of the Gastro 2009 International Working Group. | journal = Acta Neuropathol | volume = 118 | issue = 2 | pages = 271-301 | month = Aug | year = 2009 | doi = 10.1007/s00401-009-0527-y | PMID = 19360428 }}</ref>
**Most pathology practises do not report much.
**Most pathology practises do not report much.
<pre>
TERMINAL ILEUM, CECUM, COLON (ASCENDING, TRANSVERSE AND SIGMOID), COLECTOMY:
- SMALL BOWEL, CECUM, AND COLON WITHIN NORMAL LIMITS.
- FOUR LYMPH NODES NEGATIVE FOR MALIGNANCY ( 0 POSITIVE / 4 ).
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.
COMMENT:
Several stains were done:
CD117: interstitial cells of Cajal present, no apparent decrease.
SMA: no significant myocyte loss.
Gomori trichrome: no abnormal fibrosis apparent.
Tau: submucosal plexus and myenteric plexus present, no abnormalities apparent.
</pre>


=See also=
=See also=

Revision as of 12:47, 26 April 2013

The colon smell like poo... 'cause that's where poo comes from. This article also covers the rectum and cecum as both have a similar mucosa.

It commonly comes to pathologists because there is a suspicion of colorectal cancer or a known history of inflammatory bowel disease (IBD).

An introduction to gastrointestinal pathology is found in the gastrointestinal pathology article. The anus is dealt with in a separate article.

Technically, the rectum and cecum are not part of the colon. Thus, inflammation of the rectum should be proctitis and inflammation of the cecum should be cecitis.

Common clinical problems

Obstruction

Top three (in adults):[1]

Bleeding

Mnemonic CHAND:[2]

Infectious colitis with bleeding - causes:

  • Enterohemorrhagic Escherichia coli (EHEC) -- commonly 0157:H7.
  • Campylobacter jejuni.
  • Clostridium difficile.
  • Shigella.

Infectious colitis in the immunosuppressed:

Grossing

Types of specimens

Introduction to colorectal surgery:

  1. Colonic resection - remove a piece of large bowel.
  2. Total colectomy - leaves rectum and anus.[5]
  3. Subtotal colectomy - part of colon removed --or-- some of the rectum remains.
  4. Right hemicolectomy - right colon + distal ileum.
  5. Lower anterior resection (LAR) - proximal rectum +/- sigmoid (for proximal rectal malignancies).
    • Specimens have should have intact mesorectum - total mesorectal excision (TME) - reduces local recurrence.[6]
  6. Abdominoperineal resection (APR) - anus + rectum - results in a permanent stoma (for distal rectal malignancies).
  7. Stoma - these are often done emergently and then get cut-out after the patient's condition has settled.

Images:

Identifying the specimen

  • Transverse colon - has omentum.
  • Ascending colon - usu. comes with ileocecal valve and a bit of ileum.
  • Descending colon - has a bare area.
  • Rectum - has adventitia.
    • Pathologists define it as starting where the adventitia starts/the serosal surface no longer completely surrounds the large intestine.[8]
    • Anatomists define it in relation to the third sacral vertebra.[9]

Image:

Lymph nodes

Quirke method

  • Bowel is not opened - it is fixed... then sliced.[11][12]

Standard method

  • Bowel is prep'ed by opening it along the antimesenteric side.
  • Dimensions - length, circumference at both margins.
  • Radial margin/circumferential margin - should be painted.
    • Rectum starts/sigmoid ends @ place where serosa ends on the posterior aspect of the bowel.
      • The proximal, anterior aspect of the rectum has serosa, i.e. it is not painted.

Common non-neoplastic disease

Colorectal polyps

Polyps are the bread & butter of GI pathology. They are very common.

Main types:

  • Hyperplastic - most common, benign.
  • Adenomatous - quite common, pre-malignant.
  • Hamartomatous - rare, weird & wonderful.
  • Inflammatory, AKA inflammatory pseudopolyps - associated with IBD.

Most common (images):

Ischemic colitis

  • AKA colonic ischemia.
  • AKA ischemia of the colon.

General

  • May occur together with ischemic enteritis, in which case it is known as ischemic enterocolitis.

Etiology - anything that leads to vascular occlusion:

Possible associated pathology:

Closely related:

Note:

  • Ischemia = compromised blood supply.

Gross

Features - location:[13]

  • Luminal part (mucosa & submucosa) affected - edema.
  • Splenic flexture of colon commonly affected (vascular watershed).

Note:

  • May have pseudomembranes (classically assoc. with C. difficile colitis), i.e. mimics an infectious process.
  • DDx for pseudomembranes:[14]
    • C. difficile induced pseudomembranous colitis.
    • Ischemic colitis.
    • Volvulus.
    • Necrotizing infections.
    • ... anything that causes severe mucosal injury.
  • Radiologic correlate = bowel wall thickening.

Microscopic

Features:

  • Withering crypts - important.
    • Colonic epithelium has decreased cytoplasm - NC ratio increased.
    • Usually with decreased goblet cells.
  • Crypt loss/drop-out.
    • Less intestinal crypts present.
  • Lamina propria hyalinization.
    • Dense pink material replaces loose connective tissue.
  • Submucosa hyalinization.
  • +/-Pseudomembranes (microscopic):[14]
    • Loss of surface epithelium.
    • PMNs in lamina propria.
    • +/-Capillary fibrin thrombi.

Note:

  • Pseudomembranes arise from the crypts - considered acute.

DDx:

Images:

Sign out

Biopsy

TRANSVERSE COLON, BIOPSY:
- SEVERE ACTIVE COLITIS WITH ATTENUATED EPITHELIAL CYTOPLASM AND ULCERATION.
- CELLULAR DEBRIS.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

COMMENT:
The attenuated cytoplasm is compatible with ischemia; however, it is not 
accompanied with other suggestive findings (crypt drop out, lamina propria 
fibrosis, pseudomembranes).  The crypt architecture is test tube-like.

The differential diagnosis includes: ischemia, drug reaction, infectious 
etiologies and, less likely, inflammatory bowel disease. Clinical 
correlation is required.

Short version

LEFT COLON AND SIGMOID COLON, RESECTION:
- PSEUDOMEMBRANOUS COLITIS, SEE COMMENT.
- ONE LYMPH NODE NEGATIVE FOR MALIGNANCY ( 0 POSITIVE / 1 ).
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

COMMENT:
Pseudomembrane formation is a non-specific finding.  It is consistent with ischemia;
however, it may be seen in other contexts, including infection. Clinical correlation is
required.

Long version

RECTOSIGMOID, RESECTION:
- BOWEL WALL ISCHEMIA WITH PERFORATION, SEROSITIS, MICROABSCESS FORMATION AND FOCAL 
POORLY FORMED PSEUDOMEMBRANES.
- NEGATIVE FOR MALIGNANCY.
- PLEASE SEE COMMENT.

COMMENT:
There is no evidence of inflammatory bowel disease:
The unaffected mucosa does not have obvious architectural distortion. No granulomas are
identified. The inflammation is largely associated with necrosis/ischemic changes
and favoured to be reactive.

The poorly formed pseudomembranes are associated with mural ischemic changes; they do not
specifically suggest an infection in this context.

The blood vessels do not show a vasculitis, or significant atherosclerosis.  Thrombi are
seen on several sections and found predominantly in the (smaller) veins. 

Considerations are thrombosis, thromboembolism, mechanical vascular compromise, and
infectious etiologies.  A vascular compromise is favoured as the underlying cause. 

Clinical and radiologic correlation is suggested.

Another long version

SIGMOID COLON, RESECTION:
- BOWEL WALL ISCHEMIA WITH PERFORATION, SEROSITIS, AND FOCAL POORLY FORMED
PSEUDOMEMBRANES.
- MILD ATHEROSCLEROSIS.
- DIVERTICULAR DISEASE.
- TWO LYMPH NODES NEGATIVE FOR MALIGNANCY ( 0 POSITIVE / 2 ).
- PLEASE SEE COMMENT.

COMMENT:
The sections show the changes of acute and chronic ischemic colitis (submucosal fibrosis,
lamina propria hyalinization, focal crypt drop-out, decreased goblet cells, pigmented
macrophages in the lamina propria, intraepithelial neutrophils).

No granulomas are identified. The inflammation is largely associated with
the necrosis/ischemic changes and favoured to be reactive.

The poorly formed pseudomembranes are associated with mural ischemic changes; they do not
specifically suggest an infectious etiology in this context.

The blood vessels do not show a vasculitis. However, focal neutrophilic perivascular 
inflammation is seen; this is probably a reactive process. No vascular thrombi are 
identified.

The findings are compatible with perforation secondary to a foreign body in the setting of
chronic ischemia.

Micro

Negative for ischemic colitis

The sections show colorectal mucosa with preservation of the crypt density and epithelium with a normal nuclear-to-cytoplasm ratio. There is no apparent lamina propria hyalinization. The muscularis mucosa is prominent. Focally, lymphoid aggregates are present.

No cryptitis is present. Neutrophils are not apparent in the lamina propria. No erosions are identified.

The epithelium matures appropriately from the crypt base to the surface.

Diverticular disease

Diverticulitis redirect here.
  • AKA diverticulosis.

General

  • Very common.

Complications:

  • Diverticulitis.
  • Diverticular-associated colitis[18] - rare.

Gross

  • Corrugated - like cardboard.
  • Wall thickening (reactive).[19]

Endoscopic image: DD (WC).

Microscopic

Features:

  • Mucosa/submucosa invagination into the musuclaris propria (MP).
    • At the site the blood vessels supplying the mucosa and submucosa penetrate the MP.[20]

Image:

Sign out

RECTO-SIGMOID, LARGE BOWEL RESECTION:
- PERFORATED DIVERTICULITIS WITH SEROSITIS AND ABSCESS FORMATION.
- SUBMUCOSAL FIBROSIS.
- ONE LYMPH NODE NEGATIVE FOR MALIGNANCY ( 0 POSITIVE / 1 ).
- NEGATIVE FOR MALIGNANCY.
SIGMOID COLON, SIGMOIDECTOMY:
- DIVERTICULAR DISEASE WITHOUT DIVERTICULITIS.
- NEGATIVE FOR MALIGNANCY.

Pseudomembranous colitis

General

  • Pseudomembranous colitis is a histomorphologic description which has a DDx. In other words, it can be caused by a number of things.

DDx of pseudomembranous colitis:[14]

Etiology:

  • Anything that causes a severe mucosal injury.

Gross

Features:[22]

  • Pseudomembranes:
    • Pale yellow (or white) irregular, raised mucosal lesions.
    • Early lesions: typical <10 mm.
  • Interlesional mucosa often near normal grossly.

Images:

Microscopic

Features:[14]

  • Heaped necrotic surface epithelium.
    • Described as "volanco lesions" - this is what is seen endoscopically.
  • PMNs in lamina propria.
  • +/-Capillary fibrin thrombi.

Notes:

Images:

Volvulus

General

  • Uncommonly comes to pathology.
  • It is essentially a radiologic diagnosis.
  • In the context of autopsy, it is a gross diagnosis.

Gross

  • Intestine folded over itself - typically leads to ischemia.

Images:

Microscopic

Features:

DDx - essentially anything that causes ischemia:

Sign out

RECTOSIGMOID, RESECTION:
- MURAL ISCHEMIA WITH PERFORATION, SEROSITIS, MICROABSCESS FORMATION AND POORLY FORMED PSEUDOMEMBRANES.
- SUBMUCOSAL FIBROSIS.
- NEGATIVE FOR MALIGNANCY.

COMMENT:
The findings are consistent with volvulus and the submucosal fibrosis suggests this may have been recurrent.

Inflammatory diseases

Inflammatory bowel disease

The bread 'n butter of gastroenterology. A detailed discussion of IBD is in the inflammatory bowel disease article. It comes in two main flavours (Crohn's disease, ulcerative colitis).

Microscopic

Features helpful for the diagnosis of IBD - as based on a study:[25]

  • Basal, i.e. crypt base, plasmacytosis with severe chronic inflammation,
  • Crypt architectural abnormalities, and
  • Distal Paneth cell metaplasia.
    • Paneth cells should not be in the left colon[26] - if you see 'em think of IBD and other long-standing injurious processes.
    • Some claim that (friendly right colonic) paneth cells and paneth cell metaplasia look quite different and can be distinguished.[27]

Microscopic colitis

Microscopic colitis may refer to a microscopic manifestation of an unspecified disease process that can be apparent macroscopically. This section deals with a pair of diseases (lymphocytic colitis and collagenous colitis) that are considered to only have microscopic manifestations and characteristic clinical presentation.

General

Presentation:

  • Chronic diarrhea, non-bloody.[28]

Notes:

Classification

  • Lymphocytic colitis (LC).
  • Collagenous colitis (CC).

Note:

  • Some believe that LC and CC are different time points in the same process-- but this is unproven.[28]

Epidemiology

  • Age: a disease of adults - usually 50s.
  • Sex:
    • LC males ~= females,[28]
    • CC females:males = 20:1.[28]
  • Drugs are associated with LC and CC.
    • NSAIDs - posulated association/weak association,
    • SSRIs (used primarily for depression) - moderate association, dependent on specific drug.
  • Associated with autoimmune disorders - celiac disease, diabetes mellitus, thyroid disorders and arthritis.[29]
  • No increased risk of colorectal carcinoma.[29]

Treatment

  • Sometimes just follow-up.
  • Steroids - budesonide -- short-term treatment.[29]

Gross

  • As the name suggests, they are microscopic, i.e. endoscopic examination is normal.

Microscopic

Lymphocytic colitis

Features:

  • Lots of intraepithelial lymphocytes (>=20/100 lymphocytes/surface epithelial cells[29]) and
  • Lymphocytes in the lamina propria.

Significant negatives:[30]

  • No neutrophils.
  • No crypt distortion.

DDx:

Image:

Collagenous colitis

Features:

  • Intraepithelial lymphocytes, and
  • lymphocytes in the lamina propria.
  • Collagenous material in the lamina propria (pink on H&E) -- key feature.
    • Can be demonstrated with a trichrome stain -- collagen = green on trichrome.
    • Subepithelial collagen needs to be >= 10 micrometres thick for Dx.[29]
      • 8 micrometres is the diameter of a RBC.
      • The normal thickness of the subepithelial collagen is 3 micrometres.[29]
    • Thickening "follows the crypts from the surface" - useful for differentiating from tangential sections of the basement membrane.[31]
    • Collagen may envelope capillaries - useful to discern from basement membrane.[31]

Notes:

  • CC is typically more prominent in the proximal colon - may reflect concentration gradient of offending causitive agents.[29]
  • Significant negative findings:[30]
    • No PMNs.
    • No crypt distortion.
  • Should not be diagnosed in the cecum - as it (normally) has a thickened subepithelial collagen band.[citation needed]

Images:

Sign out

ASCENDING COLON, BIOPSY:
- LYMPHOCYTIC COLITIS.

Micro

Lymphocytic colitis

The sections show colonic mucosa with abundant intraepithelial lymphocytes (>20 lymphocytes/100 surface epithelial cells). The glandular architecture is within normal limits. No thickened collagen band is apparent below the epithelium.

There are no granulomas. No neutrophilic cryptitis is apparent. The epithelium matures appropriately to the surface.

Diversion colitis

Diversion proctitis redirect here.

General

  • Segment of de-functioned bowel due to surgical diversion, i.e. stoma (ileostomy or colostomy).
  • Diagnosis dependent on history - key point.

Gross

Features:[32]

  • Ulceration - classic.
  • Surgical changes, e.g. fibrotic-appearing thickened wall.
    • May not be apparent.

Microscopic

Features:[32]

  • Follicular lymphoid hyperplasia - key feature.[33]
    • Abundant lymphoid nodules.
  • Plasma cells and lymphocytes.
  • +/-Changes of an active colitis - uncommon:[34]
    • Cryptitis.
    • Crypt abscesses.

Notes:

  • May show IBD-like changes.[35]
    • IBD should not be diagnosed on a diverted segment of bowel.

DDx:[36]

Images:

Sign out

SIGMOID COLON, BIOPSIES:
- MILD ACTIVE COLITIS WITH LAMINA PROPRIA FIBROSIS, SEE COMMENT.
- NEGATIVE FOR DYSPLASIA.

COMMENT:
No granulomas are identified.  Follicular lymphoid hyperplasia is not identified;
however, there is no definite submucosa present.

Diverted segments of bowel can have inflammatory bowel disease-like changes.

In the context of a diverted segment of bowel, the findings are compatible with
a diversion colitis.

Eosinophilic colitis

General

Clinical features:[37]

  • Abdominal pain
  • Diarrhea +/-blood.
  • +/-Weight loss.

Gross

Features - endoscopic:[37]

  • Edema.
  • Granular appearance.

Microscopic

Features:[37]

  • Abundant eosinophils - no agreed upon number.
    • "Most use 20/HPF" [38] - a definition that suffers from HPFitis.
      • There is variation along the large bowel - normal in rectum <10/HPF, normal in cecum <30/HPF (???).[38]

DDx:[37]

Image:

Sign out

DESCENDING COLON, BIOPSY:
- COLONIC MUCOSA WITH MILD EOSINOPHILIA, SEE COMMENT.
- NEGATIVE FOR DYSPLASIA.

COMMENT:
Focally, there are up to 40 eosinophils / 0.2376 mm*mm (approx. field area at 400X). This
is a non-specific finding. No eosinophilic crypt abscesses are seen. No (neutrophilic)
cryptitis is present. Clinical correlation is suggested.
DESCENDING COLON, BIOPSY:
- COLONIC MUCOSA WITH MILD EOSINOPHILIA, SEE COMMENT.
- NEGATIVE FOR ACTIVE COLITIS.
- NEGATIVE FOR DYSPLASIA.

COMMENT:
There are up to 40 eosinophils / 0.2376 mm*mm (field area at 400X). This is a 
non-specific finding.  The differential diagnosis includes inflammatory bowel 
disease, infection (especially helminths), a drug reaction, and autoimmune 
disorders (e.g. Churg-Strauss syndrome, celiac disease, scleroderma). Clinical 
correlation is required.

Infectious

Infectious colitis

This section covers non-specific colitides that appear to have an infective etiology.

General

  • Common.
  • Diarrhea - typical symptom.

Gross

  • +/-Erythema on endoscopy.

Microscopic

Features:

  • Neutrophils predominant - key feature.[39]
    • The neutrophils are often superficial - they go to were the bad guys are.
  • No architectural distortion - if acute.

DDx:

IHC

Done if the patient is immunosuppressed, or there is clinical or morphological suspicion:

Sign out

ASCENDING COLON, BIOPSY:
- MILD ACTIVE COLITIS, SEE COMMENT.

COMMENT:
There is are no granulomas.  The crypt architecture is normal.  A benign lymphoid nodule is
present.

The differential diagnosis includes infective etiologies, early inflammatory
bowel disease and ischemia.  The histomorphology is more in keeping with an infective
etiology as neutrophils are a predominant feature; however, clinical correlation is
required.

Cytomegalovirus colitis

  • Abbreviated CMV colitis.

General

  • Uncommon.
  • Immunosuppressed population at risk, e.g. transplant recipients, individuals with HIV.

Microscopic

Features:

  • Enlarged nucleus - classically in endothelial cells.

DDx:

Images:

IHC

  • CMV +ve.

Others:

  • HSV-1.
  • HSV-2.
  • VZV.
  • EBV.

Intestinal spirochetosis

  • AKA intestinal spirochetes; more specifically colonic spirochetes, colonic spirochetosis.

General

  • Caused by spirochetes[41][42] - specifically Brachyspira piloicoli[43] (previously Serpulina pilosicoli[44]) and Brachyspira aalborgi.
  • Very rare cause of diarrhea, associated with male homosexual behaviour.

Symptoms:[42]

  • Watery diarrhea, abdominal pain, +/-blood per rectum.

Treatment:[45]

  • Metronidazole.

Microscopic

Features:

  • Hyperchromatic fuzz on luminal aspect of epithelial cells; at brush border.

DDx:

Images:

Special stains

  • Silver stains highlight 'em (e.g. Warthin-Starry stain).

Amebiasis

  • May also be spelling amoebiasis.

General

May cause:[48]

  • Dysentery (diarrhea containing mucus and/or blood in the feces).
  • Colitis.
  • Liver abscess.

Microscopic

Features:

  • Entamoeba histolytica are round/ovoid eosinophilic bodies ~ 40-60 micrometers in maximal dimension.
    • Found in bowel lumen.
    • Ingest RBCs.

Image:

Cryptosporidiosis

General

  • Usually in immune incompetent individuals, e.g. HIV/AIDS.

Microscopic

Features:

  • Uniform spherical nodules 2-4 micrometres in diameter, typical location - GI tract brush border.
    • Bluish staining of brush border key feature - low power.

Rectal pathology

Solitary rectal ulcer

  • AKA solitary ulcer syndrome of the rectum, abbreviated SUS.
  • AKA solitary rectal ulcer syndrome.
  • Mucosal prolapse syndrome may be used as a synonym; however, it encompasses other entities.[49]

General

  • Clinically may be suspected to a malignancy - biopsied routinely.
  • Mucosal ulceration.
  • "Three-lies disease":[50]
  1. May not be solitary.
  2. May not be rectal -- can be in left colon.
  3. May not be ulcerating -- non-ulcerated lesions: polypoid and/or erythematous.

Note: Each of the words in solitary rectal ulcer is a lie.

Epidemiology

  • Typically younger patients - average age of presentation ~30 years in one study.[51]
  • Rare.

Clinical presentation

  • Usually presents as BRBPR ~ 85% of cases.[51]
  • Abdominal pain present in approx. 1/3.[51]
    • May be very painful.

Treatment:

  • Usually conservative, i.e. non-surgical.
  • Resection - may be done for fear of malignancy.

Gross

  • Classically, anterior or anterolateral wall of the rectum.[50]

Microscopic

Features:[50][52]

  • Fibrosis of the lamina propria.
  • Thickened muscularis mucosa with abnormal extension to the lumen.
  • +/-Mucosa ulceration.
  • +/-Submucosal fibrosis.

DDx:

IHC

  • p53 -ve.
    • May be used to help exclude adenocarcinoma.

Rectal prolapse

General

  • Usually close to the anal verge.
  • Rare forms can occasionally be confused with cancer.[53]

Microscopic

Features:[54]

  • "Fibromuscular hyperplasia" - key feature:
    • Fibrosis (submucosa, lamina propria).
    • Muscularis mucosae is "too superficial" (muscle in the lamina propria).
  • Surface ulceration + inflammation (neutrophils).
  • +/-Serration of epithelium at the surface.

Notes:

  • Important negative: no nuclear atypia.

Images:

Neoplastic disease

Colorectal Tumours

These are very common. The are covered in a separate article entitled colorectal tumours.

Neuroendocrine tumour

Goblet cell carcinoid

Described in detail in the appendix article.
  • AKA crypt cell carcinoma.
  • Biphasic tumour; features of carcinoid tumour and adenocarcinoma.

Other

Pseudomelanosis coli

  • AKA melanosis coli.[55]

General

  • Not melanin as the name melanosis coli suggests; it is actually lipofuscin (in macrophages).[56]
  • Endoscopist may see brown pigmentation of mucosa and suspect the diagnosis.
  • Presence may lead to endoscopic misinterpretation of colitis severity.[57]

Epidemiology

Gross

  • Brown pigmentation of the mucosa, esp. cecum and proximal colon.

Image:

Microscopic

Features:

  • Brown granular pigment - in the lamina propria.
    • Typically more prominent in the cecum and proximal colon.[56]

Images:

Notes:

  • DDx of brown pigment:
    • Lipofuscin - comes with age (can be demonstrated with a PAS stain[59] or Kluver-Barrera stain[60]).
      • Melanosis coli.
    • Old haemorrhage, i.e. hemosiderin-laden macrophages (may be demonstrated with Prussian blue stain[61]).
    • Melanin (from melanocytes) - rare in colon (may be demonstrated with a Fontana-Masson stain[62] -- though not so useful in the GI tract).
    • Foreign material (e.g. tattoo pigment) - not seen in GI tract.

Stains

Sign out

ASCENDING COLON, BIOPSY:
- PSEUDOMELANOSIS COLI.
- NEGATIVE FOR ACTIVE COLITIS.
- NEGATIVE FOR DYSPLASIA.

Angiodysplasia

General

  • Causes (lower) GI haemorrhage.
  • Generally, not a problem pathologists see.
  • May be associated with aortic stenosis; known as Heyde syndrome.[64]

Epidemiology:

  • Older people.

Etiology:

  • Thought to be caused by the higher wall tension of cecum (due to larger diameter) and result from (intermittent) venous occlusion/focal dilation of vessels.[65]

Gross

  • Cecum - classic location.

Note:

Microscopic

Features:[66]

  • Dilated vessels in mucosa and submucosa.

Drugs

Sodium polystyrene sulfonate

  • AKA Kayexalate.

General

  • Used to treat hyperkalemia - as may be seen in renal failure.

Microscopic

Features:[67]

Image:

Graft-versus host disease

  • Abbreviated as GVHD.
  • Seen in the context of bone marrow transplants.

Bowel transplant

The histology of bowel transplant rejection is identical to GVHD - see GVHD.

Chronic constipation

General

Causes:

  • Tumour.
  • Adhesions - due to previous surgery.
  • Neuropathy.[68]
  • Congenital defect (Hirschsprung's disease).
  • Myopathy.[68]
  • Medications/substance use.
  • Idiopathic.

Gross

  • No changes.

Microscopic

Features:

  • Colon within normal limits.
    • Look for the Ganglion cells.
    • Look for interstitial cells of Cajal (with CD117).

Stains & IHC

Work-up if no tumour is identified:[69][70]

  • Routine H&E.
  • Smooth muscle actin - confirm myocyte loss.
  • Gomori trichrome - examine connective tissue.
  • CD117 - to look for the interstitial cells of Cajal.
    • <50% the expected = abnormal.[70]
      • Normal numbers not defined.
  • HU - neuronal marker.[71]

Sign out

  • A long list of things to report is contained the recommendation of a working group.[70]
    • Most pathology practises do not report much.
TERMINAL ILEUM, CECUM, COLON (ASCENDING, TRANSVERSE AND SIGMOID), COLECTOMY:
- SMALL BOWEL, CECUM, AND COLON WITHIN NORMAL LIMITS.
- FOUR LYMPH NODES NEGATIVE FOR MALIGNANCY ( 0 POSITIVE / 4 ).
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

COMMENT:
Several stains were done:
 CD117: interstitial cells of Cajal present, no apparent decrease.
 SMA: no significant myocyte loss.
 Gomori trichrome: no abnormal fibrosis apparent.
 Tau: submucosal plexus and myenteric plexus present, no abnormalities apparent.

See also

References

  1. URL: http://www.emedicine.com/EMERG/topic65.htm. Accessed on: 28 June 2011.
  2. TN 2007 G29.
  3. Golden MP, Hammer SM, Wanke CA, Albrecht MA (September 1994). "Cytomegalovirus vasculitis. Case reports and review of the literature". Medicine (Baltimore) 73 (5): 246–55. PMID 7934809.
  4. Kandiel A, Lashner B (December 2006). "Cytomegalovirus colitis complicating inflammatory bowel disease". Am. J. Gastroenterol. 101 (12): 2857–65. doi:10.1111/j.1572-0241.2006.00869.x. PMID 17026558.
  5. http://www.allaboutbowelsurgery.com/shared/stoma_care/stoma_surgery/procedures/surgery_colon/subtotal.htm
  6. Arbman, G.; Nilsson, E.; Hallböök, O.; Sjödahl, R. (Mar 1996). "Local recurrence following total mesorectal excision for rectal cancer.". Br J Surg 83 (3): 375-9. PMID 8665198.
  7. URL: http://pathinfo.wikia.com/wiki/Rectum. Accessed on: 17 September 2012.
  8. Lester, Susan Carole (2010). Manual of Surgical Pathology (3rd ed.). Saunders. pp. 339. ISBN 978-0-323-06516-0.
  9. URL: http://www.bartleby.com/107/249.html. Accessed on: 19 October 2012.
  10. Bilimoria KY, Bentrem DJ, Stewart AK, et al. (September 2008). "Lymph node evaluation as a colon cancer quality measure: a national hospital report card". J. Natl. Cancer Inst. 100 (18): 1310–7. doi:10.1093/jnci/djn293. PMID 18780863. http://www.medscape.com/viewarticle/581463.
  11. West NP, Morris EJ, Rotimi O, Cairns A, Finan PJ, Quirke P (September 2008). "Pathology grading of colon cancer surgical resection and its association with survival: a retrospective observational study". Lancet Oncol. 9 (9): 857–65. doi:10.1016/S1470-2045(08)70181-5. PMID 18667357.
  12. West NP, Finan PJ, Anderin C, Lindholm J, Holm T, Quirke P (July 2008). "Evidence of the oncologic superiority of cylindrical abdominoperineal excision for low rectal cancer". J. Clin. Oncol. 26 (21): 3517–22. doi:10.1200/JCO.2007.14.5961. PMID 18541901.
  13. Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 852. ISBN 0-7216-0187-1.
  14. 14.0 14.1 14.2 14.3 Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 837-8. ISBN 0-7216-0187-1.
  15. Tan, J.; Pretorius, CF.; Flanagan, PV.; Pais, A. (2012). "Adverse drug reaction: rosuvastatin as a cause for ischaemic colitis in a 64-year-old woman.". BMJ Case Rep 2012. doi:10.1136/bcr.11.2011.5270. PMID 22744258.
  16. Fabra, I.; Roig, JV.; Sancho, C.; Mir-Labrador, J.; Sempere, J.; García-Ferrer, L. (Jan 2011). "[Cocaine-induced ischemic colitis in a high-risk patient treated conservatively].". Gastroenterol Hepatol 34 (1): 20-3. doi:10.1016/j.gastrohep.2010.10.005. PMID 21237534.
  17. Appu, S.; Thompson, G. (Nov 2001). "Gangrenous ischaemic colitis following non-steroidal anti-inflammatory drug overdose.". ANZ J Surg 71 (11): 694-5. PMID 11736840.
  18. Mulhall, AM.; Mahid, SS.; Petras, RE.; Galandiuk, S. (Jun 2009). "Diverticular disease associated with inflammatory bowel disease-like colitis: a systematic review.". Dis Colon Rectum 52 (6): 1072-9. doi:10.1007/DCR.0b013e31819ef79a. PMID 19581849.
  19. Nicholson, BD.; Hyland, R.; Rembacken, BJ.; Denyer, M.; Hull, MA.; Tolan, DJ. (Aug 2011). "Colonoscopy for colonic wall thickening at computed tomography: a worthwhile pursuit?". Surg Endosc 25 (8): 2586-91. doi:10.1007/s00464-011-1591-7. PMID 21359889.
  20. West, AB.. "The pathology of diverticulitis.". J Clin Gastroenterol 42 (10): 1137-8. doi:10.1097/MCG.0b013e3181862a9f. PMID 18936652.
  21. URL: http://histology-group28.wikispaces.com/DigestiveSystemProject. Accessed on: 23 August 2011.
  22. URL: http://radiology.uchc.edu/eAtlas/GI/1749.htm. Accessed on: 22 May 2012.
  23. Abdulkader, I.; Cameselle-Teijeiro, J.; Forteza, J. (Apr 2003). "Signet-ring cells associated with pseudomembranous colitis.". Virchows Arch 442 (4): 412-4. doi:10.1007/s00428-003-0779-1. PMID 12684766.
  24. URL: http://pathsrvr.rockford.uic.edu/inet/GI/GI%20Station%201.htm. Accessed on: 9 April 2012.
  25. Tanaka M, Riddell RH, Saito H, Soma Y, Hidaka H, Kudo H (January 1999). "Morphologic criteria applicable to biopsy specimens for effective distinction of inflammatory bowel disease from other forms of colitis and of Crohn's disease from ulcerative colitis". Scand. J. Gastroenterol. 34 (1): 55–67. PMID 10048734.
  26. Tanaka M, Saito H, Kusumi T, et al (December 2001). "Spatial distribution and histogenesis of colorectal Paneth cell metaplasia in idiopathic inflammatory bowel disease". J. Gastroenterol. Hepatol. 16 (12): 1353–9. PMID 11851832. http://www3.interscience.wiley.com/resolve/openurl?genre=article&sid=nlm:pubmed&issn=0815-9319&date=2001&volume=16&issue=12&spage=1353.
  27. Rubio CA, Nesi G (2003). "A simple method to demonstrate normal and metaplastic Paneth cells in tissue sections". In Vivo 17 (1): 67–71. PMID 12655793.
  28. 28.0 28.1 28.2 28.3 URL: http://emedicine.medscape.com/article/180664-overview. Accessed on: 31 May 2010.
  29. 29.0 29.1 29.2 29.3 29.4 29.5 29.6 29.7 Tysk C, Bohr J, Nyhlin N, Wickbom A, Eriksson S (December 2008). "Diagnosis and management of microscopic colitis". World J. Gastroenterol. 14 (48): 7280-8. PMID 19109861. http://www.wjgnet.com/1007-9327/14/7280.asp. Cite error: Invalid <ref> tag; name "pmid19109861" defined multiple times with different content
  30. 30.0 30.1 http://hopkins-gi.nts.jhu.edu/pages/latin/templates/index.cfm?pg=disease1&disease=29&organ=6&lang_id=1
  31. 31.0 31.1 Bell, D. 4 Mar 2009.
  32. 32.0 32.1 Edwards, CM.; George, B.; Warren, B. (Jan 1999). "Diversion colitis--new light through old windows.". Histopathology 34 (1): 1-5. PMID 9934577.
  33. Yeong, ML.; Bethwaite, PB.; Prasad, J.; Isbister, WH. (Jul 1991). "Lymphoid follicular hyperplasia--a distinctive feature of diversion colitis.". Histopathology 19 (1): 55-61. PMID 1916687.
  34. Ma, CK.; Gottlieb, C.; Haas, PA. (Apr 1990). "Diversion colitis: a clinicopathologic study of 21 cases.". Hum Pathol 21 (4): 429-36. PMID 2318485.
  35. Yantiss, RK.; Odze, RD. (Jan 2006). "Diagnostic difficulties in inflammatory bowel disease pathology.". Histopathology 48 (2): 116-32. doi:10.1111/j.1365-2559.2005.02248.x. PMID 16405661.
  36. Thorsen, AJ. (Feb 2007). "Noninfectious colitides: collagenous colitis, lymphocytic colitis, diversion colitis, and chemically induced colitis.". Clin Colon Rectal Surg 20 (1): 47-57. doi:10.1055/s-2007-970200. PMC 2780148. PMID 20011361. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2780148/.
  37. 37.0 37.1 37.2 37.3 37.4 Alfadda, AA.; Storr, MA.; Shaffer, EA. (2011). "Eosinophilic colitis: an update on pathophysiology and treatment.". Br Med Bull 100: 59-72. doi:10.1093/bmb/ldr045. PMC 3165205. PMID 22012125. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3165205/.
  38. 38.0 38.1 38.2 Okpara, N.; Aswad, B.; Baffy, G. (Jun 2009). "Eosinophilic colitis.". World J Gastroenterol 15 (24): 2975-9. PMC 2702104. PMID 19554649. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2702104/. Cite error: Invalid <ref> tag; name "pmid19554649" defined multiple times with different content
  39. 39.0 39.1 Iacobuzio-Donahue, Christine A.; Montgomery, Elizabeth A. (2005). Gastrointestinal and Liver Pathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Churchill Livingstone. pp. 324. ISBN 978-0443066573.
  40. Karlitz, JJ.; Li, ST.; Holman, RP.; Rice, MC. (Jan 2011). "EBV-associated colitis mimicking IBD in an immunocompetent individual.". Nat Rev Gastroenterol Hepatol 8 (1): 50-4. doi:10.1038/nrgastro.2010.192. PMID 21119609.
  41. Amat Villegas I, Borobio Aguilar E, Beloqui Perez R, de Llano Varela P, Oquiñena Legaz S, Martínez-Peñuela Virseda JM (January 2004). "[Colonic spirochetes: an infrequent cause of adult diarrhea]" (in Spanish; Castilian). Gastroenterol Hepatol 27 (1): 21–3. PMID 14718105.
  42. 42.0 42.1 URL: http://www.jhasim.com/files/articlefiles/pdf/XASIM_Master_6_5_May_Vignette.pdf. Accessed on: 25 April 2011.
  43. Margawani, KR.; Robertson, ID.; Hampson, DJ. (Feb 2009). "Isolation of the anaerobic intestinal spirochaete Brachyspira pilosicoli from long-term residents and Indonesian visitors to Perth, Western Australia.". J Med Microbiol 58 (Pt 2): 248-52. doi:10.1099/jmm.0.004770-0. PMID 19141744. http://ukpmc.ac.uk/abstract/MED/19141744/abstract/MED/19141744?ukpmc_extredirect=http://dx.doi.org/10.1099/jmm.0.004770-0.
  44. URL: http://www.cdc.gov/ncidod/eid/vol12no05/05-1180.htm. Accessed on: 28 June 2011.
  45. Calderaro A, Bommezzadri S, Gorrini C, et al. (November 2007). "Infective colitis associated with human intestinal spirochetosis". J. Gastroenterol. Hepatol. 22 (11): 1772–9. doi:10.1111/j.1440-1746.2006.04606.x. PMID 17914949.
  46. URL: http://www.health.state.ny.us/diseases/communicable/amebiasis/fact_sheet.htm. Accessed on: 17 June 2010.
  47. Fernandes, H.; D'Souza, CR.; Swethadri, GK.; Naik, CN.. "Ameboma of the colon with amebic liver abscess mimicking metastatic colon cancer.". Indian J Pathol Microbiol 52 (2): 228-30. PMID 19332922. http://www.ijpmonline.org/article.asp?issn=0377-4929;year=2009;volume=52;issue=2;spage=228;epage=230;aulast=Fernandes.
  48. Mortimer, L.; Chadee, K. (Mar 2010). "The immunopathogenesis of Entamoeba histolytica.". Exp Parasitol. doi:10.1016/j.exppara.2010.03.005. PMID 20303955.
  49. Abid, S.; Khawaja, A.; Bhimani, SA.; Ahmad, Z.; Hamid, S.; Jafri, W. (2012). "The clinical, endoscopic and histological spectrum of the solitary rectal ulcer syndrome: a single-center experience of 116 cases.". BMC Gastroenterol 12: 72. doi:10.1186/1471-230X-12-72. PMID 22697798.
  50. 50.0 50.1 50.2 Crespo Pérez L, Moreira Vicente V, Redondo Verge C, López San Román A, Milicua Salamero JM (November 2007). "["The three-lies disease": solitary rectal ulcer syndrome"] (in Spanish; Castilian). Rev Esp Enferm Dig 99 (11): 663–6. PMID 18271667. http://www.grupoaran.com/mrmUpdate/lecturaPDFfromXML.asp?IdArt=459864&TO=RVN&Eng=1.
  51. 51.0 51.1 51.2 Chong VH, Jalihal A (December 2006). "Solitary rectal ulcer syndrome: characteristics, outcomes and predictive profiles for persistent bleeding per rectum". Singapore Med J 47 (12): 1063–8. PMID 17139403. http://www.sma.org.sg/smj/4712/4712a7.pdf.
  52. Malik, AK.; Bhaskar, KV.; Kochhar, R.; Bhasin, DK.; Singh, K.; Mehta, SK.; Datta, BN. (Jul 1990). "Solitary ulcer syndrome of the rectum--a histopathologic characterisation of 33 biopsies.". Indian J Pathol Microbiol 33 (3): 216-20. PMID 2091997.
  53. Brosens LA, Montgomery EA, Bhagavan BS, Offerhaus GJ, Giardiello FM (November 2009). "Mucosal prolapse syndrome presenting as rectal polyposis". J. Clin. Pathol. 62 (11): 1034–6. doi:10.1136/jcp.2009.067801. PMC 2853932. PMID 19861563. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2853932/.
  54. Schneider A, Fritze C, Bosseckert H, Machnik G (1988). "[Primary clinical, endoscopic and histologic findings in solitary rectal ulcer]" (in German). Dtsch Z Verdau Stoffwechselkr 48 (3-4): 183–9. PMID 3234303.
  55. URL: http://www.medicinenet.com/melanosis_coli/article.htm. Accessed on: 4 March 2011.
  56. 56.0 56.1 56.2 Freeman HJ (July 2008). ""Melanosis" in the small and large intestine". World J. Gastroenterol. 14 (27): 4296-9. PMID 18666316. http://www.wjgnet.com/1007-9327/14/4296.asp.
  57. Zapatier, JA.; Schneider, A.; Parra, JL. (Dec 2010). "Overestimation of ulcerative colitis due to melanosis coli.". Acta Gastroenterol Latinoam 40 (4): 351-3. PMID 21375218.
  58. 58.0 58.1 Pardi, DS.; Tremaine, WJ.; Rothenberg, HJ.; Batts, KP. (Apr 1998). "Melanosis coli in inflammatory bowel disease.". J Clin Gastroenterol 26 (3): 167-70. PMID 9600362.
  59. Kovi J, Leifer C (July 1970). "Lipofuscin pigment accumulation in spontaneous mammary carcinoma of A/Jax mouse". J Natl Med Assoc 62 (4): 287–90. PMC 2611776. PMID 5463681. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2611776/pdf/jnma00512-0077.pdf.
  60. URL: http://education.vetmed.vt.edu/curriculum/VM8054/labs/Lab2/Examples/exkluvbarr.htm. Accessed on: 5 May 2010.
  61. URL: http://education.vetmed.vt.edu/curriculum/VM8054/labs/Lab2/Examples/exprussb.htm. Accessed on: 5 May 2010.
  62. URL: http://education.vetmed.vt.edu/curriculum/VM8054/labs/Lab2/Examples/exfontana.htm. Accessed on: 5 May 2010.
  63. Benavides SH, Morgante PE, Monserrat AJ, Zárate J, Porta EA (August 1997). "The pigment of melanosis coli: a lectin histochemical study". Gastrointest. Endosc. 46 (2): 131–8. PMID 9283862.
  64. Hui YT, Lam WM, Fong NM, Yuen PK, Lam JT (August 2009). "Heyde's syndrome: diagnosis and management by the novel single-balloon enteroscopy". Hong Kong Med J 15 (4): 301–3. PMID 19652242. http://www.hkmj.org/abstracts/v15n4/301.htm.
  65. Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 854. ISBN 0-7216-0187-1.
  66. 66.0 66.1 Hemingway, AP. (Apr 1988). "Angiodysplasia: current concepts.". Postgrad Med J 64 (750): 259-63. PMID 3054852.
  67. Abraham SC, Bhagavan BS, Lee LA, Rashid A, Wu TT (May 2001). "Upper gastrointestinal tract injury in patients receiving kayexalate (sodium polystyrene sulfonate) in sorbitol: clinical, endoscopic, and histopathologic findings". Am. J. Surg. Pathol. 25 (5): 637-44. PMID 11342776. http://meta.wkhealth.com/pt/pt-core/template-journal/lwwgateway/media/landingpage.htm?issn=0147-5185&volume=25&issue=5&spage=637.
  68. 68.0 68.1 68.2 Knowles, CH.; Farrugia, G. (Feb 2011). "Gastrointestinal neuromuscular pathology in chronic constipation.". Best Pract Res Clin Gastroenterol 25 (1): 43-57. doi:10.1016/j.bpg.2010.12.001. PMID 21382578.
  69. IAV. 15 December 2009.
  70. 70.0 70.1 70.2 Knowles, CH.; De Giorgio, R.; Kapur, RP.; Bruder, E.; Farrugia, G.; Geboes, K.; Gershon, MD.; Hutson, J. et al. (Aug 2009). "Gastrointestinal neuromuscular pathology: guidelines for histological techniques and reporting on behalf of the Gastro 2009 International Working Group.". Acta Neuropathol 118 (2): 271-301. doi:10.1007/s00401-009-0527-y. PMID 19360428.
  71. Barami K, Iversen K, Furneaux H, Goldman SA (September 1995). "Hu protein as an early marker of neuronal phenotypic differentiation by subependymal zone cells of the adult songbird forebrain". J. Neurobiol. 28 (1): 82–101. doi:10.1002/neu.480280108. PMID 8586967.