Gastrointestinal Pathology Quiz

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which statement accurately describes the location affected by acute compromise of major vessels?

Anemia primarily affects the jejunum and ileum.

Watershed zones include the splenic flexure and sigmoid colon. (correct)

The inferior mesenteric arterial circulation primarily supplies the upper rectum.

Transmural infarction is typical in the duodenum.

What primary feature distinguishes Hirschsprung disease in its pathology?

Increased tone of the lower esophageal sphincter

Absence of ganglion cells in the affected segment (correct)

Inflammation of the rectal mucosa

Proliferation of smooth muscle cells

What is the primary cause of transmural infarction in the intestine?

Acute vascular obstruction of major blood vessels. (correct)

Chronic hypoperfusion due to systemic diseases.

Defective absorption in malabsorption syndromes.

Localized bacterial infection causing inflammation.

What is the primary mechanism causing symptoms in achalasia?

Increased tone of the lower esophageal sphincter Signup and view all the answers

Which feature is characteristic of the histology observed in acute ischemic intestine?

Atrophy or sloughing of surface epithelium. Signup and view all the answers

Which diagnostic method is important for confirming Hirschsprung disease?

Immunohistochemical staining for acetylcholinesterase Signup and view all the answers

Which factor contributes to the vulnerability of the intestinal surface epithelium to ischemic injury?

The arrangement of capillaries running alongside the glands. Signup and view all the answers

What is the primary risk associated with pyloric stenosis?

Nutritional deficiencies due to vomiting Signup and view all the answers

In chronic ischemia, which complication can occur despite being uncommon?

Stricture formation within the intestinal lumen. Signup and view all the answers

Which symptom is commonly associated with achalasia?

Dysphagia for solids and liquids Signup and view all the answers

What indicates the presence of malabsorption in an individual?

Chronic diarrhea with defective absorption of multiple nutrients. Signup and view all the answers

What characterizes the morphology of Hirschsprung disease?

A lack of Meissner and Auerbach plexuses Signup and view all the answers

What role do neutrophils play in acute ischemic episodes upon reperfusion?

They are recruited within hours to aid in inflammation. Signup and view all the answers

What is the incidence of Hirschsprung disease in live births?

1 in 5000 live births Signup and view all the answers

Which statement best characterizes the impact of acute ischemic disease on the intestinal mucosa?

Transmural infarction leads to injury in all three wall layers. Signup and view all the answers

Which condition is characterized by functional obstruction and proximal dilation of intestine?

Hirschsprung disease Signup and view all the answers

What is the underlying cause of secondary achalasia in Chagas disease?

Destruction of the myenteric plexus Signup and view all the answers

Which treatment is NOT indicated for achalasia?

Antibiotics for infection Signup and view all the answers

What characterizes the esophageal changes in reflux esophagitis?

Metaplasia of esophageal epithelium Signup and view all the answers

What is a significant risk associated with Barrett esophagus?

Increased risk of esophageal adenocarcinoma Signup and view all the answers

Which of the following describes a common histological finding in esophageal varices?

Dilated subepithelial venous plexi Signup and view all the answers

The most common symptom of gastroesophageal reflux disease (GERD) is:

Acid regurgitation Signup and view all the answers

What physiological mechanism primarily prevents reflux of gastric contents into the esophagus?

Tone of the lower esophageal sphincter Signup and view all the answers

Which feature distinguishes Barrett esophagus from normal esophageal mucosa?

Presence of dysplastic cells Signup and view all the answers

Mallory-Weiss syndrome is primarily caused by:

Severe retching or vomiting Signup and view all the answers

What primary condition often leads to the development of esophageal varices?

Cirrhosis of the liver Signup and view all the answers

Which statement about the esophagus is false?

It is resistant to acid but sensitive to abrasion. Signup and view all the answers

What is a key characteristic of the epithelial changes in Barrett esophagus?

Squamous to glandular metaplasia Signup and view all the answers

What can severe, chronic gastroesophageal reflux lead to in certain patients?

Esophageal stricture Signup and view all the answers

In the context of chronic GERD, what happens to the esophageal tissue?

It develops intestinal metaplasia. Signup and view all the answers

Which inflammatory cell type is NOT typically found in the epithelial layer of esophageal lesions?

Basophils Signup and view all the answers

What is the primary mechanism by which portal hypertension leads to esophageal varices?

Altered venous drainage pathways Signup and view all the answers

What histological feature is characterized by increased numbers of specific immune cells in the lamina propria in conditions such as celiac disease?

Lamina propria infiltration Signup and view all the answers

Which condition is primarily associated with the overgrowth of Clostridium difficile following antibiotic use?

Pseudomembranous colitis Signup and view all the answers

Which of the following symptoms is NOT typically associated with enterocolitis?

Acute renal failure Signup and view all the answers

What is a common consequence of untreated celiac disease?

Permanent intestinal injury Signup and view all the answers

What characterizes the histopathology of fully developed Clostridium difficile-associated colitis?

Formation of pseudomembranes Signup and view all the answers

In celiac disease, the histological finding of villous atrophy suggests which of the following?

Chronic inflammation Signup and view all the answers

Which of the following immune cells is typically increased in the lamina propria in response to intestinal inflammation?

Neutrophils Signup and view all the answers

In the context of antibiotic-associated diarrhea, how does Clostridium difficile affect the colonic microbiota?

Facilitates overgrowth due to disrupted balance Signup and view all the answers

What is the distinguishing feature of collagenous colitis?

Presence of dense subepithelial collagen layer Signup and view all the answers

Which statement correctly describes lymphocytic colitis?

It presents with chronic, nonbloody, watery diarrhea. Signup and view all the answers

In the context of diverticular disease, what does diverticulosis refer to?

Acquired pseudo-diverticular outpouchings Signup and view all the answers

Which demographic is most commonly affected by collagenous colitis?

Middle-aged and older women Signup and view all the answers

What is a common characteristic of both collagenous and lymphocytic colitis?

Both present with chronic, nonbloody, watery diarrhea Signup and view all the answers

What is the primary cause of colonic diverticula formation?

Abnormal colonic muscularis propria structure Signup and view all the answers

At what age does the prevalence of diverticulosis begin to significantly increase?

60 years old Signup and view all the answers

Which autoimmune diseases are strongly associated with lymphocytic colitis?

Graves disease and rheumatoid arthritis Signup and view all the answers

Study Notes

Esophageal Atresia and Tracheoesophageal Fistula

Discovered shortly after birth, usually due to regurgitation during feeding
Esophageal atresia: a thin, non-canalized cord replaces a segment of esophagus, causing mechanical obstruction
Atresia most common at or near the tracheal bifurcation, often associated with a fistula
Fistula connects the upper or lower esophageal pouches to a bronchus or trachea
Fistula can occur without atresia
Complications include aspiration, suffocation, pneumonia, and severe fluid and electrolyte imbalances

Diaphragmatic Hernia

Occurs when incomplete diaphragm formation allows abdominal viscera to herniate into the thoracic cavity
Severe cases cause pulmonary hypoplasia, which is incompatible with life

Omphalocele

Closure of the abdominal musculature is incomplete, leading to abdominal viscera herniating into a ventral membranous sac.
Location: Centered
Content: Primarily intestines, frequently including colon, bladder, and sometimes gonads.
Associated with other congenital anomalies (15%)

Gastroschisis

Similar to omphalocele, but involves all layers of the abdominal wall (peritoneum to skin).
Location: Right side
Content: Intestines, liver, and sometimes spleen, colon or bladder
Frequently associated with other congenital anomalies (40-80%)

Meckel Diverticulum

A blind pouch of the ileum, usually within 2 feet of the ileocecal valve
Approximately 2 inches long
More common in males
Often asymptomatic, but symptomatic cases usually present before age 2 (approximately 4%).
"Rule of 2s": 2% of population, 2 ft from ileocecal valve, 2 in long

Pyloric Stenosis

Congenital hypertrophy of the pyloric sphincter
Infants feed well initially but progressively develop projectile vomiting
Vomiting usually begins at 2–3 weeks old, or even earlier
Projectile vomiting occurs after feeding
Infants are frequently hungry and voracious eaters

Hirschsprung Disease

Also called congenital aganglionic megacolon
Absence of ganglion cells in the distal portion of the intestine
Results in functional obstruction
Occurs in approximately one in 5,000 live births

Achalasia

Increased tone of the lower esophageal sphincter (LES) due to impaired smooth muscle relaxation
Characterized by incomplete LES relaxation, increased LES tone, and esophageal aperistalsis
Symptoms include dysphagia (difficulty swallowing, for both solids and liquids), chest pain, and difficulty with belching
Secondary achalasia may occur with Chagas disease, where Trypanosoma cruzi infection damages the myenteric plexus

Mallory-Weiss Syndrome

Longitudinal mucosal tears near the gastroesophageal junction, often associated with severe retching or vomiting, frequently related to alcohol abuse.
Usually presents with hematemesis (vomiting blood)
Risk factors include alcohol abuse and hiatal hernias.

Boerhaave's Syndrome

Complete rupture of the lower esophageal sphincter, often associated with severe retching or vomiting, usually unrelated to alcohol.
May cause chest pain, and hypotension
Presents with subq emphysema, and often with crepitus upon auscultation.

Reflux Esophagitis

Stratified squamous epithelium of esophagus is resistant to abrasion but sensitive to acid.
Submucosal glands in the proximal and distal esophagus secrete mucin and bicarbonate.
Lower esophageal sphincter (LES) tone prevents reflux of highly acidic gastric contents into the esophagus.
Reflux of gastric contents into the esophagus is the most frequent cause of esophagitis and the associated condition: Gastroesophageal Reflux Disease (GERD).

Histology of Reflux Esophagitis

Inflammatory cells, eosinophils, neutrophils, and T cells
Acanthosis and papillomatosis
Basal cell hyperplasia
Ballooned squamous cells
Vascular ectasia in lamina propria

Esophageal Varices

Venous blood from the GI tract passes through the liver, via the portal vein, before returning to the heart.
Portal hypertension results in the development of collateral channels.
These collateral veins lead to the development of varices in the distal esophagus and proximal stomach.
Varices commonly develop in patients with cirrhosis (especially alcoholic liver disease)

How Liver Disease Leads to Bleeding Varices

Cirrhosis increases intrahepatic vascular resistance, potentially due to architectural distortion and inadequate nitric oxide
Portal hypertension results from increased intrahepatic resistance and splanchnic arteriolar vasodilation
Increased pressure in these vessels can cause varices to form and rupture, leading to bleeding

Barrett's Esophagus

Complication of chronic gastroesophageal reflux disease (GERD)
Characterized by intestinal metaplasia replacing the normal esophageal squamous mucosa
Increased risk of esophageal adenocarcinoma, related to preinvasive change of dysplasia, prolonged symptoms, length of affected esophageal segments, and Caucasian race

Morphology of Barrett Esophagus

Red, velvety mucosa extending upward from the gastroesophageal junction
Alternating with light-brown, columnar (gastric) mucosa
Length of affected esophagus associated with dysplasia risk

Histology of Barrett's Esophagus

Intestinal-type metaplasia manifested as squamous esophageal epithelium replacement by goblet cells

Chronic Gastritis (H. pylori)

Common cause of chronic gastritis
Spiral-shaped or curved bacilli, frequently present in gastric biopsies (of almost all gastric ulcer and/or gastritis patients)
Primarily transmitted through the fecal-oral route in childhood
The most common clinical presentation is predominantly antral gastritis with normal or increased acid production.

Autoimmune Gastritis

Accounts for less than 10% of chronic gastritis cases
Typically spares the antrum and is associated with hypergastrinemia
Marked by antibodies to parietal cells and intrinsic factor

Gastric Intestinal Metaplasia

Presence of goblet cells replacing the squamous esophageal epithelium
Result of failed involution of the vitelline duct

Mucosal Atrophy and Intestinal Metaplasia

Long-standing chronic gastritis, particularly affecting the body and fundus, can lead to significant loss of parietal cell mass
Associated with intestinal metaplasia (goblet cells) and increased risk of gastric adenocarcinoma

Intestinal Obstruction

Hernias- Protrusion of serosa-lined pouch of peritoneum through a defect in abdominal wall
Adhesions- Fibrous bridges forming between organs, possibly leading to internal herniation
Volvulus- Twisting of a bowel loop about its mesenteric point of attachment.
Intussusception- A segment of bowel telescoping into another segment, potentially leading to obstruction, compression of mesenteric vessels, and infarction

Ischemic Bowel Disease

Majority of the GI tract is supplied by the celiac, superior mesenteric, and inferior mesenteric arteries. Interconnections result in the small intestine and colon’s ability to withstand decreased blood flow from one artery.
Acute compromise of a major vessel can lead to infarction of meters of intestine
Infarction can range from mucosal to transmural.
Watershed zones (e.g., splenic flexure, rectosigmoid colon), where arterial supplies meet, are highly susceptible.

Infectious Enterocolitis

Can present with a wide range of symptoms: Diarrhea, abdominal pain, urgency, perianal discomfort, incontinence, hemorrhage, and/or fever
Viral, bacterial, and parasitic infections.

Pseudomembranous Colitis

Caused primarily by Clostridium difficile
Associated with disruption of normal colonic microbiota by antibiotic use (C. difficile overgrowth, most often)
Presentation is characterized by pseudomembranes, made of inflammatory cells and debris at sites of mucosal injury
While pseudomembranes can occur with infections or ischemia, the histopathology of C. difficile is distinctive.

Whipple Disease

Rare, multi-visceral chronic disease
Characterized by malabsorption and/or lymphatic obstruction, as well as arthritis, and diarrhea
Microbial infection caused by Tropheryma whipplei, a gram-positive actinomycete.
Morphologically characterized by macrophages containing PAS-positive, diastase-resistant granules, which are lysosomes containing partially digested bacteria
The macrophages can accumulate in the small intestinal lamina propria, mesenteric lymph nodes, joints, cardiac valves, and other locations.

Inflammatory Bowel Disease (IBD)

Chronic inflammatory condition caused by inappropriate mucosal immune activation
Two main forms:
- Crohn's disease: Can affect any area of the gastrointestinal tract (typically transmural). Presenting symptoms: diarrhea, abdominal pain, abdominal cramping.
- Ulcerative colitis: Involves the rectum and colon, limited to the mucosal and submucosal layer, in a continuous fashion
Distal ileum, ileocecal valve and cecum are frequently affected sites

Pathogenesis of IBD

Altered gut microbial composition is thought to play a role, triggering pro-inflammatory cytokines, including TNF-α, IL-12, and IL-23.
Loss of tolerance to commensal bacteria

Microscopic Colitis

Two forms:
- Collagenous colitis: characterized by dense subepithelial collagen layer, increased numbers of intraepithelial lymphocytes, and a mixed inflammatory infiltrate.
- Lymphocytic colitis: characterized by increased intraepithelial lymphocytes.

Sigmoid Diverticular Disease

Acquired outpouchings of the colonic mucosa
Common in adults over 60, especially the sigmoid colon
May lead to perforation if obstructed

Malabsorption

Presence of diarrhea and steatorrhea, a sign of fat malabsorption
Deficiencies in fat, fat-soluble vitamins, proteins, carbohydrates, electrolytes and minerals, and water. Multiple causes (e.g., lymphatic obstruction, infections) contributing to malabsorption

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on critical concepts related to gastrointestinal pathology, including conditions like Hirschsprung disease, ischemia, and achalasia. This quiz covers vascular complications, histological features, and diagnostic methods pertaining to intestinal diseases. Perfect for medical students and professionals looking to assess their understanding of these topics.