• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/117

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

117 Cards in this Set

  • Front
  • Back
  • 3rd side (hint)
The presence of granulomas in an IBD setting are most indicative of which type of IBD?
Crohn's colitis
Which type of IBD, Crohn's vs UC, demonstrates rectal sparing?
Crohn's
What are the histopathologic features of IBD?
crypt architectural distortion
Basal lymphoplasmacytosis
What is the histologic difference between sarcoidosis and IBD?
Sarcoidosis may have scattered non-caseating granulomas (as seen in Crohn's). However, other features of IBD will not be present (no crypt branching, no basal lymphoplasmacytosis)
What are the differences between Shigella colitis and IBD?
Shigella colitis shows active inflammation (may have extensive ulceration with granulation tissue), but usually no features of chronic changes.
What are the histologic features of Clostridium colitis?
features of acute ischemic colitis with associated pseudomembranes
What are the classic histologic findings of Crohn's disease?
Transmural lymphoid aggregates
Deep fissures extending into muscularis propria
Epithelioid granulomas
Rectal sparing
Crohn's disease is associated with what mutation?
CARD15/NOD2 gene

contains caspase recruitment domains (CARDs)
serves as an intracellular receptor for bacterial products in monocytes
transduces signals leading to NF-kappaB activation
Is p-ANCA more likely to be positive in Crohn's or Ulcerative colitis?
Ulcerative colitis

Crohn's: 10% p-ANCA positive
UC: 75% p-ANCA positive
List the differential diagnosis for the following findings:
1. Necrosis of the superficial portion of the mucosa
2. Hemorrhage into the lamina propria
3. Pseudomembranes
4. Preservation of crypt architecture
Ischemic colitis
Neonatal necrotizing enterocolitis
Various infectious colitides (including C difficile and enterohemorrhagic E coli colitis)
What is pseudoinvasion?
misplaced epithelium within the submucosa--similar grade of dysplasia as mucosal epithelium, have lobular configuration. NO angular, infiltrating glands

Inflammatory cells usually surround misplaced epithelium; also hemorrhage and hemosidering deposition.

Associated mucin pools are regular in shape, often associated with ruptured crypts.
What causes pseudoinvasion with a polyp?
result of herniation of glands into the submucosa secondary to torsion of the polyp stalk
What should NOT be seen with pseudoinvasion
Infiltrated angulated glands
Desmoplastic response
All of the following are features of invasive adenocarcinoma EXCEPT:
A. The submucosa contains dispersed angulated glands associated with irregularly shaped mucin pools
B. The epithelium lining submucosal glands often has a greater degree of atypia than the epithelium lining mucosal glands
C. The submucosal glands are associated with a desmoplastic stromal reaction
D. Hemorrhage and hemosiderin are minimal or absent
E. Groups of submucosal glands are invested by lamina propria inflammatory cells
E. In invasive adenoCA, groups of submucosal glands are not characteristically invested by lamina propria inflammatory cells (as may be seen in pseudoinvasion).
Describe the microscopic features of ganglioneuroma.
Expansion of the lamina propria by bland spindle cells interspersed by variable numbers of ganglion cells (single or in clusters)
What is the inheritance pattern of familial adenomatous polyposis syndrome (FAP)?
autosomal dominant
What is the mutation in FAP?
germline mutation in APC (adenomatous polyposis coli)

What signaling pathway does it regulate?
Negative regulation of the Wnt signaling pathway
What is Gardener's Syndrome?
FAP plus:
multiple osteomas
epidermal cysts and fibromas
What is Turcot's syndrome?
hereditary colonic cancer syndrome plus:
CNS tumors
What type of colonic cancer syndrome is associated with microsatelite instability?
HNPCC (hereditary nonpolyposis colorectal cancer)
AKA Lynch Syndrome
Micro Diagnosis: Polypoid lesion on colonoscopy demonstrates submucosal nodule of spindle cells with lymphoid follicles (nodular lymphoid cuff).
Likely schwannoma
DDX: GIST, leiomyoma

What stains will help?
S100: Positive in schwannoma
CD117: Positive in GIST
Desmin: Positive in leiomyoma

Schwannomas are negative for CD117 and desmin
True/False. GI schwannomas are associated with neurofibromatosis type 1.
False

GI schwannomas are not associated with NF-1 OR NF-2.
What is the most common location for GI schwannomas?
Stomach, but can also occur in colon

Benign or malignant?
benign
True/False: GI schwannomas affect men and women equally.
True
True/False. Most of the patient's with diverticular disease are asymptomatic.
True.

What is the percentage of individuals over the age of 60 affected by diverticulosis in Western civilizations?
50%
What is the cause of diverticular disease?
Increased luminal pressure along with focal weakness in the colonic wall.

With what type of diet is it associated?
Low fiber diets
True/False. Diverticulosis can only occur in the colon.
False.

Though majority are in the colon, can occur elsewhere, including the small intestine
True/False. Diverticular disease can mimic IBD.
True.

Diverticular diseae is associated with chronic segmental colitis in the distribution of the diverticula and CAN mimic idiopathic inflammatory bowel disease.
True/False. Rectal carcinoids are usually associated with carcinoid syndrome.
False.

What is their prognosis?
usually good, though malignant cases do occur (11-14% of cases).
What stain is positive in both rectal carcinoids AND prostatic adenocarcinoma?
Prostatic acid phosphatase (PAP)

What stain is negative in rectal carcinoids and positive in prostatic adenocarcinoma?
Prostate specific antigen (PSA)
True/False. Extramammary Paget's disease in the anogenital region is associated with HPV.
False

What disease IS it commonly associated with?
half of cases are associated with synchronous or metachronous malignancy (often colorectal carcinoma)
What is the differential diagnosis for Paget's disease?
Pagetoid Bowen's disease & melanoma

How can IHC help?
Paget's: +mucin, +CEA, +EMA, +CK7, & -S100
How can IHC help differentiate Pagets associated with colorectal carcinoma and primary cutaneous intraepithelial malignancy w/ sweat gland differentiation?
Assoc. w/ colon CA: +CK20, -GCDFP15
Primary cutaneous w/ sweat gland diff.: -CK20, +GCDFP15
What genotype of HPV is associated with AIN?
16 and 18
Females with anal intraepithelial neoplasa (AIN) are at an increased risk of developing what type of carcinoma?
vulvar or cervical squamous cell carcinoma
True/False. Anal intraepithelial neoplasia is often multicentric.
True
True/False. Most cases of anal intraepithelial neoplasa are discovered as incidental findings on minor surgical specimens for benign conditions.
True
What patient population is at an increased risk for developing AIN?
immunocompromised patients
Microscopic features of mucosal prolapse:
--erosion of surface epithelium w/ adjacent regenerative and/or hyperplastic changes
--vascular congestion
--fibrosis of lamina propria
--hyperplasia of muscularis mucosa w/ extension of fibromuscular strands into lamina propria ("muscularization of the lamina propria")
List some types of prolapse induced polyps.
--Polypoid variants of solitary rectal ulcer syndrome (SRUS)
--Inflammatory cloacogenic polyp (ICP)
--Inflammatory cap polyps
--Polypoid prolapsing mucosa in diverticular disease
--Inflammatory myoglandular polyps
What are the typical gross findings and presentation of inflammatory cloacogenic polyps?
located within the anal canal
may be solitary or multiple
usually 1-2 cm
usually sessile

What is the typical patient population?
predominantly middle aged patients, though cases in children have been described.
True/False. Patients with mucosal prolapse are NOT at an increased risk of developing carcinoma.
True
True/False. Juvenile polyps are usually solitary and not associated with a syndrome.
True
Describe the pathologic findings in Juvenile polyposis syndrome.
Multiple juvenile polyps in the gastrointestinal tract (most commonly colorectum, but also stomach and SI)

Some patients have predominant colorectal involvement; however there is also a subset with polyps limited to the stomach
True/False. Patients with juvenile polyposis syndrome are NOT at an increased risk for developing adenocarcinoma.
FALSE.

JPS patients have an increased risk of adenoCA of the colon, stomach, small intestine, biliary tract, and pancreas
What is the pattern of inheritance for juvenile polyposis syndrome?
autosomal dominant

What germline mutation is associated with a subset of patients in JPS?
mutations in SMAD4/DPC4
All of the following are true regarding juvenile polyposis syndrome EXCEPT:
a) patients have increased risk of adenoCA (>50% by age 60)
b) germline mutations in SMAD4/DPC4 tumor suppresor gene are associated with a subset of patients with this syndrome
c) this syndrome is an autosomal dominant disorder
d) polyps in this syndrome are always restricted to the SI
e) polyps in this syndrome may show areas of dysplasia
D: Polyps in JPS may occur in the colorectum, stomach, or small bowel
Which of the following is NOT true regarding MALT lymphoma?
a) Regression may be seen with antibiotic treatment
b) The translocation t(11;18) is seen in a significant number of cases
c) Immunophenotype: CD5, CD20, cyclin D1 positive; CD10 negative
d) Dutcher bodies may be seen
e) It may transform to a high-grade lesion
C. They are NEGATIVE for CD5 and cyclin D1
What is the full name of MALT lymphoma?
extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue

What is the translocation associated with it?
t(11;;18) found in significant number

Trisomy 3 found in about a 1/3 of cases
What infection is MALT lymphoma associated with?
H. pylori

What is the significance of this association?
MALT lymphoma may regress after eradication of H. pylori
What are the histologic findings in MALT lymphoma?
dense, monotonous population of centrocyte-like cells that may infiltrate the glandular epithelium

Plasma cell differentiation is common
TRUE/FALSE: Dutcher bodies may be present in MALT lymphoma.
True

What about plasma cell differentiation in MALT?
Plasma cell differentiation is common in MALT
Describe the immunophenotype of extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue.
Postive: CD20, bcl-2
Variably positive: CD43 (about 1/3)
Negative: CD5, cyclin D1, CD10
True/False: Marginal zone B-cell lymphoma is a high grade B-cell lymphoma.
False. It is a low grade lymphoma that may progress to a high grade lymphoma.
Which of the following is NOT true regarding GVHD in the gut?
a) It represents the response of immunocompetent recipient cells to histocompatibility antigens of the donor.
b) It frequently presents with diarrhea
c) It is rarely seen in recipients of solid organ transplants
d) Necrosis of crypts is seen in severe forms
e) CMV infection can produce similar histologic findings
A. It represents the response of immunocompetent DONOR cells to histocompatibility antigens of the recipient.
How common is GHVD in allogenic BMT recipients versus solid organ recipients?
allogenic BMT: develops in up to 50% of cases

solid organ: rare occasions
What other entity can produce similar histologic findings to GVHD?
CMV
What are the common presenting complaints in GHVD?
Diarrhea, nausea, vomiting, and abdominal pain
Describe the range of histologic findings in GVHD in the gut.
Grade 1: apoptosis of individual crypt cells--see apoptotic bodies

Severe: necrosis of multiple crypts
Which of the following is TRUE regarding lymphomatoid polyposis?
a) It is low grade
b) It is associated with H. pylori
c) It affects the small bowel more often than the colon
d) It has autosomal dominant inheritance
e) It typically presents at an advanced stage with spread to beyond the abdomen.
E.
It is an aggressive lymphoma. No assoc. w/ H. pylori. No known predisposing factors. Not a familial syndrome. Seen more commonly in the colon.
What is the immunophenotype of lymphomatoid polyposis?
Positive: CD20, CD5, cyclin D1
Negative: CD10

What type of lymphoma is this?
Mantle cell
What is the typical presenting stage of mantle cell lymphoma presenting as lymphomatoid polyposis?
Advanced stage--involvement of mesenteric lymph nodes, spleen, and even beyond the abdomen (including peripheral LN and bone marrow)
Q42: The following histologic feature is rare in collagenous colitis:
a) Increased intraepithelial lymphocytes
b) Moderate eosinophilic inflammation in the lamina propria
c) Entrapment of inflammatory cells and capillaries in a subepithelial collagen layer
d) Marked crypt architectural distortion
e) All of the above
D--Occasional distorted crypts may be found in collagenous colitis, but marked crypt distortion is rare.

The rest of the findings are common in collagenous colitis
Q43: All of the following are associated with HNPCC EXCEPT:
a) Carcinomas with DNA microsatellite instability
b) Carcinomas with large numbers of tumor infiltrating lymphocytes
c) Proximally located large serrated polyps
d) Proximally located mucinous adenocarcinomas
e) Proximally located poorly differentiated carcinomas
C--Although some large serrated polyps in the proximal colon are precursors of colonic CA with microsatellite instability, they are not associated with HNPCC.

The remaining features are associated with HNPCC
Q44: The following syndrome is an inherited hamatomatous polyposis syndrome:
a) Cowden's syndrome
b) Peutz-Jeghers' syndrome
c) Basal cell nevus syndrome
d) Neurofibromatosis type 1
e) All of the above
E--all of the above

What are some other inherited hamartomatous polyposis syndromes?
familial juvenile polyposis
multiple neuroendocrine neoplasia 2B (MEN 2B)
Bannayan-Ruvalcaba-Riley syndrome
What is a hamartomatous polyp?
overgrowth of cells native to the area in which they normally occur
What is the frequency of hamartomatous polyposis syndromes in comparison to adenomatous polyposis syndromes?
1/10 the frequency of adenomatous polyposis syndromes

hamartomatous polyposis syndromes account for <1% of colorectal cancer in North America
Q41: Which of the following is TRUE about celiac disease?
a) Most common presenting symptom in adults over 40 is diarrhea and malabsorption
b) Share the major histocompatibility complex class II HLA-DQ2 and HLA-DQ8 haplotype
c) Prevalence in the US is about 1:1000
d) Gluten is a water-soluble protein component (gliadin) of wheat
e) All of the above
B--Almost all, if not all, individuals with celiac disease share the haplotype HLA-DQ2 or HLA-DQ8

What is the actual prevalence of celiac in the US?
Approximately 1:100
What is the most common presenting symptom of celiac disease in adults over 40?
iron deficiency
True/False: Gluten is an alcohol-insoluble, water-soluble protein component (gliadin) of wheat.
FALSE. Gluten is an alcohol-SOLUBLE, water-INsoluble protein component (gliadin) of wheat
Q45: Which of the following statements is TRUE about adenomas of the small intestine?
a) Most occur in the region of the ampulla of Vater
b) They account for approximately 50% of benign small intestinal tumors
c) Patients frequently present with obstruction or intussusception
d) Patients with Peutz-Jeghers' syndrome commonly develop multiple adenomas in the proximal small intestine
e) All of the above
A--Most adenomas of the SI occur in the region of the ampulla of Vater (~25% of benign small intestine tumors)
What is the typical presentation of patients with small intestinal adenomas?
occult blood loss
rarely obstruction or intussusception
Do patient's with Petuz-Jeghers' syndrome develop multiple small intestinal adenomas?
No--may develop polyps in small intestine, but not associated with MULTIPLE polyps in the small intestine.

What other syndrome is associated with periamullary adenomas?
FAP--familial adenomatous polyposis syndrome
Q46: What molecular changes are common in the adenoma-carcinoma sequence?
a) Mutations of the APC gene
b) Mutations of the KRAS gene
c) Loss of heterozygosity at 18q21 (SMAD 2 and 4)
d) Mutations in the P53 gene
e) All of the above
E--all of this may occur in the adenoma-carcinoma sequence.

An accumulation of mutations is often necessary for carcinoma to develop
Q47: Most common congenital defect of the esophagus:
a) atresia with blind upper segment and fistula between blind lower segment and trachea
b) atresia with blind upper and lower segments and no tracheoesophageal fistula
c) atresia with blind upper segment, no lower segment, and no tracheoesophageal fistula
d) fistula between patent esophagus and trachea
e) atresia with blind upper segment forming tracheoesophageal fistula
A--the most common defect is a blind upper and lower segment with a fistule between the blind lower segment and the trachea

What are the complications?
aspiration and paroxysmal suffocation from food
Where does esophageal atresia typically occur?
near the tracheal bifurcation
True/False. Esophageal atresia is typically an isolated congenital abnormality.
False. It rarely occurs alone and is usually associated with a fistule connecting the lower or upper pouch with the trachea
True/False. Congenital defects of the esophagus are uncommon, but may be life-threatening.
True
Q48: The following statement is TRUE about granular cell tumors of the GI tract:
a) They do not react with antibody against S100 protein
b) They do not stain with PAS
c) They most commonly occur in the esophagus
d) They most commonly measure 10-30 mm
e) All of the above
C--Granular cell tumors most commonly occur in the distal esophagus

What is the actual typical size?
50% smaller than 5 mm, only 18% are 10-30 mm
What is the IHC for granular cell tumors?
Positive PAS and S-100
Q49: The following statement is TRUE regarding heterotopic pancreatic tissue in the GI tract:
a) It most commonly occurs in the colon
b) Endocrine elements are present in >75% of cases
c) It cannot be detected endoscopically
d) It can be composed of any of the normal components of pancreatic parenchyma either in isolation or in combination
e) All of the above
D--Heterotopic rests may be composed of any of the normal components of pancreatic parenchyma, either in isolation or in combination
Microscopic description for heterotopic pancreas:
May be composed of any of the normal components of pancreatic parenchyma (either in isolation or in combination)

Endocrine elements (representing islets of Langerhans) present in <50% of cases
What is the most common location of heterotopic pancreas?
Stomach
What is the gross description of heterotopic pancreas?
Small nodules, often with central dimple representing a draining duct
Question 50: The following polyposis syndrome is NOT associated with an increased risk of carcinoma of the GI tract:
A. Peutz-Jeghers' syndrome
B. Cowden's syndrome
C. Turcot's syndrome
D. Juvenile polyposis
E. None of the above
B. Cowden's syndrome
is NOT associated with carcinomas of the GI tract
What is Cowden's syndrome?
--Hamartomas of the GI tract
--Carcinomas of the breast and thyroid
--Gingival hyperplasia
Question 51: The following statement is TRUE regarding amyloidosis involving the GI tract:
A. GI involvement is common in all types of systemic amyloidosis
B. Vascular involvement by amyloid causes fragility and rupture of vessels, which can lead to ischemic colitis.
C. Histochemical stains used for amyloid include Congo red, toluidine blue, crystal violent, and thioflavine.
D. The most common area of the GI tract biopsied to diagnose amyloidosis is the rectum.
E. All of the above
E. All of the above
What is the pathogenosis of ischemic colitis in cases of amyloidosis?
When amyloidosis involves vessels of the colon, the vessels may rupture
List four helpful histochemical stains for amyloidosis.
Congo red
toluidine blue
crystal violet
thioflavine
What area of the GI tract is commonly biopsied to diagnose amyloidosis?
rectum
Question 52: Autoimmune chronic atrophic gastritis:
A. Is antral predominant
B. Is assoc. w/ increased intrinsic factor production
C. Is assoc. w/ hypergastinemia
D. Is assoc. w/ hyperchlorhydria
E. All of the above
C. is assoc. w/ hypergastrinemia
Which portion of the stomach is involved my autoimmune chronic atrophic gastritis?
it is corpus-restricted
What antibodies are present in autoimmune chronic atrophic gastritis?
antiparietal cell and anti-intrinsic factor
TRUE/FALSE. Autoimmune chronic atrophic gastritis is associated with increased intrinsic factor production without pernicious anemia.
FALSE.

it is associated with IF deficiency with OR without pernicious anemia
Describe the pathogenesis of autoimmune chronic atrophic gastritis.
Antibodies (against IF and parietal cells) destroy acid-producing parietal cells causing achlorhydria. Achlorhydria stimulates increased production of gastrin leading to hypergastrinemia
TRUE/FALSE. Autoimmune chronic atrophic gastritis is associated with achlorhydriqa and hypergastrinemia.
True
Question 53: The following statement is TRUE regarding Meckel's diverticulum:
A. It occurs in approximately 15-20% of the population
B. It is the most common congenital abnormality in the GI tract.
C. This outpouching is not a "true" diverticulum in that it does not involve all layers of the bowel wall.
D. <10% of Meckel's diverticula contain heterotopic epithelium, either gastric or pancreatic.
E. All of the above
B. It is the most common congenital abnormality in the GI tract (occurs in 1-3% of the population)
What is the underlying cause of Meckel's diverticulum?
persistence of the proximal portion of the vitelline duct
True/False. Meckel's diverticulum is a true diverticulum.
True. It involves all layers of the bowel wall.
What portion of Meckel's diverticula contain heterotopic epithelium?

What type is most common?
Up to 50%. Most contain gastric oxyntic mucosa. A smaller proportion have pancreatic tissue.
Question 54: Menetrier's disease:
A. Is characterized by marked foveolar hyperplasia.
B. Is characterized by marked inflammation.
C. Predominantly involves the antrum.
D. Is associated with hyperproteinemia.
E. All of the above
A. Menetrier's is characterized by marked foveolar hyperplasia

Inflammation is usually only modest
What is Menetrier's disease?
Rare disorder with:
- marked foveolar hyperplasia in the gastric body
- hypoproteinemia 2/2 protein-losing enteropathy.
- usually only modest inflammation
Question 55: Complete endoscopic removal of a pedunculated adenoma containing adenocarcinoma in the submucosa of its stalk is generally considered adequate treatment when the following criteria are met:
A. The CA does not extend to margin
B. There is no vascular or lymphatic invasion.
C. The CA is not poorly diff.
D. All of the above
E. None of the above (this is never considered adequate treatment for adenoma containing adenocarcinoma)
D. All of the above.

ALL of these criteria must be met in order for this to be adequate treatment
Question 56: All of the following are well-described forms of NSAID-induced injury in the colon EXCEPT:
A. Concentric diaphragm/ring-like strictures on the right side
B. Discrete erosions/ulcerations with little associated inflammation
C. Ischemic-type mucosal damage
D. Collagenous colitis
E. Marked crypt architectural distortion
E. Marked crypt architectural distortion (while a characteristic finding of IBD) is NOT a typical pattern caused by NSAID use.
List the well-described forms of NSAID-induced injury of the colon.
--concentric, diaphragm/ring-like strictures on the right side
--discrete erosions/ulcerations with little associated inflammation
--collagenous colitis
--ischemic-type mucosal damage
Question 57: The following is a TRUE statement regarding diversion colitis:
A. Its major cause is thought to be bacterial overgrowth.
B. It is assoc. w/ excess short-chain fatty acids in the fecal stream.
C. When severe, it most closely resembles crohn's disease
D. Mucosal recovery is often seen with restoration of fecal flow through the colon.
E. All of the above.
D. Mucosal recovery is often seen with restoration of fecal flow through the colon.
Describe the pathogenosis of diversion colitis.
Lack of exposure to the fecal stream renders colonic mucosa susceptible to deprivation of nutrients, particularly short-chain fatty acids.
What is the major cause of pouchitis?
bacterial overgrowth
Describe the microscopic changes in diversion colitis.
Ranges from mild increase in lamina propria inflammation to severe colitis resembling ulcerative colitis
What two interventions allow mucosal recovering in diversion colitis?
1--enemas containing short-chain fatty acids
2--restoration of fecal flow through the colon
Question 58: Granulomatous gastritis is MOST commonly associated with:
A. Lymphoma
B. Crohns disease
C. Infection due to Mycobacterium tuberculosis or Histoplasma capsulatum
D. An immune-mediated vasculitis syndrome
E. Carcinoma
B.
Granulomas in the stomach may be associated with ALL of the conditions listed; however, they are most COMMONLY associated with CROHNS DISEASE and SARCOIDOSIS
What should be included in the differential of granulomas within the stomach?
--Crohn's disease
--Sarcoidosis
--Lymphoma
--Infection (TB or histo)
--Immune-mediated vasculitis
--Carcinoma
Question 59: The following statements are true regarding Hirschsprung disease EXCEPT:
A. It may result from mutations in the RET gene.
B. It may result from mutations in the endothelin B receptor.
C. It predominates in males, M:F=4:1
D. In approx. 50% of cases the entire colon is involved.
E. The affected aganglionic segment is usually of normal caliber and the ganglionic segment proximal to the affected segment is distended.
D.
Most cases involve the rectum and the sigmoid ONLY (short-segment aganglionosis). Only RARELY is the entire colon involved.
Name two genes implicated in Hirschsprung disease.
RET gene and the endothelin B receptor
Desribe the gross findings in a colon affected by Hirschrpung disease.
Segment of colon PROXIMAL to the aganglionic segment is distended. The aganglionic segment is usually of normal caliber.
Question 60: All of the following histologic features are associated with acute infectious colitis EXCEPT:
A. Neutrophils in the lamina propria
B. Cryptitis
C. Crypt abscesses
D. Basal plasmacytosis
E. Preservation of crypt architecture
D. Basal plasmacytosis is typically NOT seen and is (in addition to status of crypt architecture) a very useful histologic feature in distinguishing acute infectious colitis from IBD.
What two findings are helpful in separating IBD from acute infectious colitis?
Presence of basal plasmacytosis (plasma cells in basal layer) and loss of normal architecture.

Both of these findings are not typical of acute infectious colitis and are more indicative of IBD.