Medicine Marrow Pg 31-40 (GIT)

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Questions and Answers

Which cytokine is considered the most potent anti-inflammatory cytokine in the body?

TNF-alpha

IL-10 (correct)

IFN-gamma

IL-6

Crohn's disease is characterized by a decrease in gut bacteria like Faecalibacterium.

True

What genetic defect is associated with early onset childhood inflammatory bowel disease?

Defect in IL-10 or IL-10 receptor function

The gene polymorphism associated with Crohn's disease is found on chromosome ______.

16 Signup and view all the answers

Match the following components with their respective roles:

CD3 = Pan T-cell marker CD25 = T-reg cell marker CD4 = Helper T-cell marker NOD2 = Gene associated with Crohn's disease Signup and view all the answers

Which demographic is associated with a higher risk of Crohn's disease compared to ulcerative colitis?

Males Signup and view all the answers

Smoking is protective against Crohn's disease.

False Signup and view all the answers

What is the impact of appendicectomy on ulcerative colitis?

Protective Signup and view all the answers

The presence of microvilli in the colon's crypts contributes primarily to ______ absorption.

water Signup and view all the answers

Match the features of ulcerative colitis (UC) and Crohn's disease (CD):

Female : Male Ratio = UC has a lower male predominance Age Peaks = CD has a single peak at younger age OCP Risk = UC does not exhibit increased risk Familial Inheritance = CD shows significant familial concordance Signup and view all the answers

Which genetic syndrome is most commonly associated with ulcerative colitis (uc) in childhood?

Turner's Syndrome Signup and view all the answers

The Wiskott-Aldrich Syndrome is caused by an autosomal dominant gene mutation.

False Signup and view all the answers

What is the primary defect causing IPEX syndrome?

Loss of FOXP3 function Signup and view all the answers

Hermansky-Pudlak Syndrome is characterized by interstitial lung disease and __________.

Oculocutaneous albinism Signup and view all the answers

Match the following syndromes with their associated features:

Wiskott-Aldrich Syndrome = Recurrent sino-pulmonary infections, eczema, thrombocytopenia Hermansky-Pudlak Syndrome = Pulmonary fibrosis, oculocutaneous albinism von Gierke's Disease = Hepatomegaly, lactic acidosis IPEX = Endocrinopathy, dermatitis, uc-like enteropathy Signup and view all the answers

What is a consequence of transmural involvement in gastroenterology?

Potential formation of fissures and fistulas Signup and view all the answers

Non-caseating granulomas can form solely within the intestine.

False Signup and view all the answers

What type of inflammation occurs in the crypts according to the findings?

Cryptitis Signup and view all the answers

The presence of _____ granulomas is noted in findings related to Crohn's disease.

non-caseating Signup and view all the answers

Match the histological findings with their descriptions:

Cryptitis = Inflammation of the crypts Crypt abscesses = Pus-filled pockets within the crypts Pyloric metaplasia = Change in the pyloric region of the intestine Lymphoid aggregates = Clusters of lymphoid tissue Signup and view all the answers

Which of the following is considered an earliest finding in diagnosing relapse in remission patients with inflammatory bowel disease?

Basal plasma cell aggregates Signup and view all the answers

Cobblestone appearance is a feature associated with Crohn's disease.

True Signup and view all the answers

What are the typical features of the ulcers seen in Crohn's Disease?

Deep, transmural, asymmetric skip lesions and aphthous ulcers. Signup and view all the answers

The condition known for transmural involvement and skip lesions is called ______.

Crohn's disease Signup and view all the answers

Match the features with their respective conditions:

Transmural involvement = Crohn's Disease Superficial mucosal involvement = Ulcerative Colitis Skip lesions = Crohn's Disease Basal plasma cell aggregates = Both conditions Signup and view all the answers

Which feature is more common in Crohn's Disease compared to Intestinal Tuberculosis?

Involvement of ICV Signup and view all the answers

Intestinal Tuberculosis always involves more than four segments of the colon.

False Signup and view all the answers

What is a key characteristic of the ileocecal valve (ICV) in Intestinal Tuberculosis?

Usually strictured and patulous Signup and view all the answers

Crohn's Disease primarily affects the terminal ileum and _____ segments of the colon.

≥4 Signup and view all the answers

Match the following features with the corresponding condition:

Crohn's Disease = Involvement of ≥4 segments Intestinal Tuberculosis = Involvement is less extensive Signup and view all the answers

What percentage of ulcerative colitis patients have pancolitis involving the rectum, sigmoid, and colon?

10-20% Signup and view all the answers

Ulcerative colitis commonly shows skip lesions throughout the colon.

False Signup and view all the answers

What is the first change observed in the mucosa of a patient with ulcerative colitis?

Erythematous mucosa with fine, granular surface Signup and view all the answers

The appearance of the colon in chronic long-standing ulcerative colitis can be described as a '______ pipe appearance.'

lead Signup and view all the answers

What is characterized by mucosal ulcers with surrounding translucent edema in the context of inflammatory bowel disease?

Target sign Signup and view all the answers

Match the following changes in ulcerative colitis with their descriptions:

Erythematous mucosa = Initial change in ulcerative colitis Pseudopolyps = Inflammatory polyp from epithelial regeneration Hemorrhagic mucosa = Presence of bleeding in the mucosa Toxic megacolon = Colon diameter greater than 6mm Signup and view all the answers

CT scanning is the preferred method for diagnosing inflammatory bowel disease.

False Signup and view all the answers

Name one appearance associated with inflammatory bowel disease as mentioned in the document.

Longitudinal ulceration, Cobblestone appearance, or Rose thorn (Transmural ulcers) Signup and view all the answers

The ______ sign implies hypervascular mesentery and is typically associated with Crohn's disease.

Comb Signup and view all the answers

Match the imaging findings with their description:

String sign = Indicates a fibrosed bowel Fat halo sign = Describes a particular appearance Target appearance = Presence of thickened colonic walls Comb sign = Sign associated with Crohn's disease Signup and view all the answers

Which of the following is NOT a finding typically associated with Crohn's disease in a barium enema?

Herniation Signup and view all the answers

Toxic megacolon is characterized by extreme dilation of the colon.

True Signup and view all the answers

What is the most common type of Crohn's disease indicated in a barium enema?

Ileocolitis Signup and view all the answers

The appearance of the colon that is often associated with inflammation or strictures is referred to as the ______ appearance.

lead pipe Signup and view all the answers

Match the following findings from a barium enema with their descriptions:

Fine mucosal granularities = Earliest change in Crohn's disease Superficial ulcerations = Shallow sores on the lining Collar stud ulcers = Characteristic collar-like appearance Toxic megacolon = Extreme dilation of the colon Signup and view all the answers

What symptom is commonly relieved by diarrhea in patients with Crohn's disease?

Episodic right lower quadrant pain Signup and view all the answers

Fistulas are abnormal connections that can occur due to Crohn's disease.

True Signup and view all the answers

Name one systemic symptom associated with Crohn's disease.

Fever Signup and view all the answers

What symptom is most commonly associated with proctitis in ulcerative colitis?

Painless bleeding PR Signup and view all the answers

Proctocolitis is characterized by small, frequent stools that may contain blood, pus, and mucus.

True Signup and view all the answers

What is the most sensitive biomarker used to assess the severity of ulcerative colitis?

Fecal calprotectin Signup and view all the answers

The endoscopic appearance of ulcerative colitis is characterized by a red, velvety mucosa with decreased vascularity and ______.

mucosal ulcerations Signup and view all the answers

Match the following clinical features with their corresponding ulcerative colitis types:

Proctitis = Painless bleeding PR Proctosigmoiditis = Streaks of blood on stool Proctocolitis = Small, frequent stools with blood, pus, and mucus Endoscopy findings = Erythematous, red, velvety mucosa Signup and view all the answers

Study Notes

Management of Inflammatory Bowel Disease

Supportive care and replacement therapy
Gene therapy

Investigations

Genetic testing

Markers of T-reg cells

CD3: Pan T-cell marker
CD25: T-reg cell
CD4: Helper T-cell

Early Onset Childhood IBD

Defect in IL-10 or IL-10 receptor function
Severe refractory IBD in early life

Pathogenesis of IBD

Exogenous and endogenous factors → Dysregulated mucosal immune response in a genetically susceptible individual.
Most potent anti-inflammatory cytokine in the body: IL-10

Ulcerative Colitis

Pathogenesis is unclear.
Overactive adaptive immune system: Th lineage.

Crohn's Disease

Genetically susceptible individuals:
- NOD2 (CARD15) gene polymorphism on chromosome 16.
Dysregulated mucosal immune response:
- Defective innate immunity:
  - Decreased clearance of intracellular organisms (mycobacterium paratuberculosis, m.avium complex)
  - Decreased defensin production from Paneth cells
  - Defective autophagy
Overactive adaptive immune system (Th lineage: Crohn's disease).
Decrease in gut bacteria like Faecalibacterium (Gut protective).

Epidemiology

Overall:
- CD > UC
- Males > Females

Comparison of UC and CD

Female : Male Ratio:
- UC: No information available
- CD: No information available
Age:
- UC: 2 peaks: 15-30 years & 70-90 years
- CD: No information available
Ethnicity:
- UC: Jews > Non-Jewish white > African American > Hispanic > Asian
- CD: No information available
Smoking:
- UC: Protective
- CD: Causative
Appendicectomy:
- UC: Protective
- CD: No association
OCP:
- UC: No increased risk
- CD: Increased risk
Familial Inheritance (Concordance):
- UC: No information available
- CD: Significant CD > UC
Antibiotics in 1st year of life:
- UC: No information available
- CD: Increases risk of IBD by 3 times

Behçet's disease

GI manifestations like Crohn's disease.
Share a common antibody: ASCA (Anti-Saccharomyces cerevisiae antibody).

Prolonged use of α-methyl dopa

Causes features similar to ulcerative colitis.

Campylobacter jejuni

Risk factor for IBD
Also causes large bowel diarrhea, Guillain Barre syndrome.

Mucosa

Villi are absent.
Crypts: Contain microvilli - water absorption.
Goblet cells: Secrete mucus.
Diarrhea > 200 ml of stool volume.

Genetic Syndromes Associated With IBD

Present as IBD in childhood:

Genetic Syndromes - UC (Non-granulomatous)

Turner's syndrome: m/c

Genetic Syndromes - CD (Granulomatous)

Wiskott-Aldrich Syndrome
von Gierke's disease
Hermansky-Pudlak syndrome

Clinical Features of Genetic Syndromes

Syndrome	Defect/Inheritance	Triad of:	Features
Wiskott-Aldrich Syndrome	WASP gene mutation (x-linked recessive)	1. Recurrent sino-pulmonary infections. 2. Recurrent eczema. 3. Recurrent thrombocytopenia (micro platelets).	Platelet dysfunction with normal platelet count.
Hermansky-Pudlak Syndrome	Autosomal recessive		Interstitial lung disease: Pulmonary fibrosis. Oculocutaneous albinism. Hypoglycemia +/- Seizures, Doll facies.
von Gierke's Disease	Glucose-6-phosphatase deficiency		Hepatomegaly. Lactic acidosis. Hyperuricemia. Hyperlipidemia.

IMMUNE POLYENDOCRINOPATHY X-LINKED SYNDROME (IPEX)

Physiology: FOXP3: Transcription factor → Normal T-reg cell function (Cell tolerance)
Pathology: Loss of FOXP3 function → Reduced cell tolerance → IPEX syndrome.
Triad of:
- Endocrinopathy (Type 1 Dm / Thyroiditis)
- Dermatitis
- uc-like enteropathy

Microscopy

Transmural involvement: Involvement extends up to the muscularis propria, potentially leading to fissures and fistulas.
Serosa involvement: This is a specific type of transmural involvement affecting the serosa layer.
Non-caseating granulomas: Granulomas are present at various levels and can even form outside the intestine.
Changes in crypts:
- Cryptitis: Inflammation of the crypts
- Crypt abscesses: Abscesses (pus-filled pockets) within the crypts.
Crypt architecture: The structure of the crypts appears normal.
Pyloric metaplasia: A change in the pyloric region of the intestine.
Lymphoid aggregates: Clusters of lymphoid tissue.
Possible causes of non-caseating granulomas:
- Sarcoidosis
- Tuberculosis
- Cat Scratch disease
- Berylliosis
- Hypersensitivity pneumonitis
- Crohn's disease

Crohn's Disease vs Intestinal Tuberculosis

Involvement of ICV:
- Crohn's disease: Common
- Intestinal Tuberculosis: Usually strictured and patulous ICV
Involvement of colon:
- Crohn's disease: ≥4 segments, especially terminal ileum and ICV
- Intestinal Tuberculosis: No information available.

Microscopy - Ulcerative Colitis

Superficial Involvement: mucosa & superficial part of submucosa
Cryptitis with loss of crypt architecture
Paneth cell metaplasia (Seen distal to hepatic flexure)
Basal plasma cell and lymphoid aggregates
- Earliest finding
- Can help in diagnosing relapse in remission patients

Factors against the diagnosis of ulcerative colitis

Transmural involvement
Skip lesions
Deep ulcers

Pathology: Crohn's Disease

Site of Involvement:
- Ileocolitis: 40-50%
- Ileitis: 30-40%
- Colitis: 15-20%

Macroscopy - Crohn's Disease

Deep, transmural, asymmetric skip lesions
Earliest finding: Aphthous ulcers → Small, translucent ulcers
Most visible finding: Linear, Serpenginous ulcers
Cobblestone appearance: The ulcers fuse longitudinally and transversely with areas of uninvolved mucosa in between
Peri rectal fissures, fistulas and abscesses
- Fistula tracts resolve by fibrosis
  - a.Thickening of the wall
  - b.Strictures

Garden Hose Appearance

Tubular lumen with extensive transmural fibrosis and stenosis seen in terminal ileum
Creeping fat: Thickened mesentery encasing the bowel wall
Note: Garden hose appearance in esophagus → well developed progressive systemic sclerosis

Pathology: Ulcerative Colitis

Site of Involvement:
- Rectum alone: 50%
- Extension to sigmoid colon: 30-40%
- Pancolitis (Rectum, sigmoid, colon involved): 10-20%
- 10-20% of pancolitis patients: Ileum involvement → Backwash ileitis

Macroscopy - Ulcerative Colitis

Superficial, continuous, symmetrical lesions
Continuous involvement: Rectum → Sigmoid → Colon → Ileum (No skip lesions)
1st Change: Erythematous mucosa with fine, granular surface
Hemorrhagic, edematous, ulcerated mucosa
Pseudopolyps: Inflammatory polyp d/t epithelial regeneration

Chronic Long-Standing UC (rare)

Lead pipe appearance (Atrophic, featureless colon):
- a.Loss of haustrations
- b.Shortening and narrowing of colon
Fulminant colitis (very rare): Toxic megacolon (Colon diameter >6mm).

Additional Information

Haustrations:
- Present (uninvolved colon)
- Absent
Lead pipe appearance: Seen on barium study

Barium Enema Radiology

Normal mucosa: A healthy lining of the colon.
Fine mucosal granularities: Tiny, granular bumps on the mucosal layer.
Superficial ulcerations: Shallow sores affecting the surface of the lining.
Extensive ulcerations: Deeper sores affecting more of the lining.
Inflammatory pseudopolyps: Small growths caused by inflammation.
Deep ulcers extending to submucosa: Deep sores that penetrate into the submucosal layer.
Collar stud ulcers: Ulcers with a characteristic collar-like appearance.
Lead pipe appearance: Abnormally uniform, straight appearance of the colon (often associated with inflammation/strictures).
Toxic megacolon: Extreme dilation of the colon.

Crohn's Disease

Clinical Features:
- Ileocolitis (most common):
  - Episodic right lower quadrant pain.
  - Relieved with diarrhea (Large bowel diarrhea d/t colitis).
- D/t Th, profile (IL-2, IFN Y):
  - Fever.
  - Weight loss.
  - Systemic symptoms.
- Jejunoileitis: Malabsorption due to inflammation of the jejunum and ileum.
- Palpable inflammatory mass: Thickening of the bowel wall due to inflammation.
- Bowel obstruction: Blockage of the bowel.
- Fistulas: Abnormal connections between the bowel and other structures (Enterovesical > Perianal).
- Fissures: Cracks in the bowel lining.
- Fibroses & strictures: Scar tissue and narrowings in the bowel.

Additional Notes - Crohn's Disease

Earliest change: Fine mucosal granularities.
Serrations producing hazy margin.
Mild narrowing of lumen.
Loss of rectal valves.
Backwash ileitis (Inflammation of terminal ileum).

Ulcerative Colitis - Clinical Features

Based on the level of involvement:

Proctitis

Painless bleeding PR (most common)
- Differential Diagnosis (D/d):
  - Hemorrhoids
  - Malignancies
Slow proximal transit → Constipation
Normal physical examination.
Systemic symptoms: very rare (Th2 lineage → Involves IL-4, 5, 13).
90% have relapsing course.

Proctosigmoiditis

Streaks of blood onto formed stool.

Proctocolitis

Large bowel diarrhea:
- 1.Small, frequent stools with blood, pus, and mucus.
- 2.Tenesmus

Fecal calprotectin

most sensitive biomarker.
used to assess disease severity, response to Rx & to diagnose relapse.

Endoscopy - Ulcerative Colitis

Symmetrical, superficial, and continuous involvement.
Findings:
- Erythematous, red, velvety mucosa (earliest).
- ↓sed vascularity → mucosal ulcerations with fine granulations and friability (Mayo score)
Lead pipe/pipestem colon (very rare in endoscopy).

Radiology - Barium Enema - Ulcerative Colitis

Target Sign: Characterized by mucosal ulcers with surrounding translucent edema.
Significance: Earliest radiologic and endoscopic finding for IBD.

CT Scan - IBD

Limited Role: CT scanning plays a limited role in diagnosing IBD, with MR enterography being preferred.
Possible findings:
- String sign: Indicates a fibrosed bowel.
- Sinus tracts: Visible on the image as a tract or channel.
- Fissures and string sign: Indicate specific pathologies.
- Target appearance: Presence of thickened colonic walls.
- Comb sign: A sign typically associated with Crohn's disease, implying hypervascular mesentery.
- Fat halo sign: Describes a particular appearance.
- Tissue Attenuation: The inner and outer layers of tissues show soft tissue attenuation, while the middle layer displays fatty attenuation.

Other Appearances - CT Scan - IBD

Longitudinal ulceration
Cobblestone appearance
Rose thorn (Transmural ulcers)

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Test your knowledge on the management and pathogenesis of Inflammatory Bowel Disease (IBD). The quiz covers supportive care, genetic factors, and the immune markers associated with both ulcerative colitis and Crohn's disease. Assess your understanding of IBD's complexities and therapeutic approaches.