Gastritis and Peptic Ulcer Disease

Overview

Gastritis and peptic ulcer disease (PUD) represent a spectrum of inflammatory and ulcerative conditions affecting the gastroduodenal mucosa. Gastritis refers to inflammation of the gastric mucosa, while PUD specifically denotes mucosal breaks extending through the muscularis mucosae in the stomach (gastric ulcer) or duodenum (duodenal ulcer). These conditions remain highly prevalent worldwide, affecting approximately 5-10% of the global population during their lifetime. [1]

The pathogenesis fundamentally involves an imbalance between aggressive factors (gastric acid, pepsin, Helicobacter pylori, NSAIDs) and protective mechanisms (mucus secretion, bicarbonate production, mucosal blood flow, prostaglandins). The discovery of H. pylori by Marshall and Warren in 1983 revolutionized our understanding of PUD, establishing infection as the primary causative factor in 70-80% of duodenal ulcers and 50-60% of gastric ulcers. [2] NSAIDs represent the second major cause, responsible for the majority of H. pylori-negative ulcers, particularly in elderly populations. [3]

Complications of PUD—including hemorrhage (15-20% of cases), perforation (2-10%), and gastric outlet obstruction (2%)—contribute significantly to morbidity and mortality, particularly in older patients and those on anticoagulation or antiplatelet therapy. [4] Modern management centers on acid suppression with proton pump inhibitors (PPIs), H. pylori eradication when present, and NSAID cessation when feasible. Despite therapeutic advances, PUD-related hospitalizations and mortality from complications remain substantial public health concerns.

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Epidemiology

Prevalence and Incidence

The lifetime prevalence of PUD ranges from 5-10% in Western populations, with significant geographical variation. [1] Incidence rates have declined substantially over recent decades in developed countries, from approximately 150-200 per 100,000 person-years in the 1960s to 50-80 per 100,000 currently. [5] This decline parallels decreasing H. pylori prevalence in younger cohorts and improved H. pylori eradication strategies.

Age Distribution

Duodenal ulcers typically present in younger adults (30-55 years), while gastric ulcers predominate in older individuals (55-70 years). [6] The increasing age of PUD patients reflects declining H. pylori prevalence in younger cohorts and increasing NSAID use in elderly populations.

Complication Rates

Complications occur in 20-25% of PUD patients, with mortality from complicated PUD remaining at 5-10% despite medical advances. [4]

Helicobacter pylori Prevalence

H. pylori infection affects approximately 50% of the global population, with marked variation by geography and socioeconomic status. [2] Prevalence exceeds 70-80% in developing countries but has declined to 20-40% in developed nations, particularly among younger generations. [8]

H. pylori association with PUD:

• Duodenal ulcer: 70-80% H. pylori-positive [2]
• Gastric ulcer: 50-60% H. pylori-positive [2]
• Uncomplicated ulcer recurrence without eradication: 60-80% per year [8]
• Ulcer recurrence after successful eradication: less than 10% per year [8]

NSAID-Associated PUD

NSAIDs are consumed regularly by 10-15% of adults, with usage increasing to > 30% in those > 65 years. [3] NSAID-associated ulcers account for the majority of H. pylori-negative PUD.

• NSAID users developing ulcers: 15-30% annually [3]
• Symptomatic ulcers in chronic NSAID users: 2-4% annually [9]
• Serious complications (bleeding/perforation): 1-2% annually [9]
• Relative risk of ulcer complications with NSAIDs: 3-5 fold [3]

Risk Factors

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Aetiology and Pathophysiology

Fundamental Pathophysiology

PUD results from an imbalance between aggressive and protective factors affecting the gastroduodenal mucosa. This classical paradigm, first articulated by Schwartz ("no acid, no ulcer"), remains relevant but incomplete without considering H. pylori and NSAIDs.

Aggressive Factors:

• Gastric acid (HCl)
• Pepsin
• H. pylori infection and associated inflammation
• NSAIDs and aspirin
• Bile acids (in gastric ulcer)
• Smoking
• Physiological stress

Protective Factors:

• Mucus-bicarbonate barrier
• Epithelial cell integrity and regeneration
• Mucosal blood flow
• Prostaglandins (PGE2, PGI2)
• Epidermal growth factor
• Mucosal immune defenses

Helicobacter pylori Pathogenesis

H. pylori, a spiral gram-negative bacterium, colonizes the gastric mucosa of approximately half the world's population. [2] The bacterium's unique adaptations enable survival in the hostile gastric environment and induction of chronic inflammation.

Exam Detail: Bacterial Virulence Factors:

1. Urease enzyme: Converts urea to ammonia and CO2, neutralizing gastric acid locally and enabling bacterial survival in the acidic environment. Ammonia also directly damages epithelial cells. [12]

2. CagA (cytotoxin-associated gene A): A 120-140 kDa protein injected into host cells via type IV secretion system. CagA-positive strains confer 2-3 fold increased risk of PUD and gastric cancer. [12]

   • Induces cellular morphological changes ("hummingbird phenotype")
   • Disrupts epithelial cell polarity and tight junctions
   • Activates inflammatory signaling pathways (NF-κB)
   • Promotes cellular proliferation and inhibits apoptosis

3. VacA (vacuolating cytotoxin A): Induces vacuolation in epithelial cells, increases membrane permeability, and triggers apoptosis. Multiple allelic variants exist with varying pathogenicity. [12]

4. Flagella: Enable motility through viscous gastric mucus layer

5. Adhesins: Facilitate bacterial attachment to gastric epithelium

Mechanism of Ulceration:

The pathogenesis varies by ulcer location, reflecting differences in acid secretion and inflammation patterns:

Duodenal Ulcer Pathogenesis:

1. H. pylori colonizes gastric antrum (cannot colonize duodenal epithelium)
2. Antral-predominant gastritis develops
3. Reduced somatostatin secretion from D cells
4. Increased gastrin secretion from G cells (loss of negative feedback)
5. Increased parietal cell mass and acid secretion (30-50% above normal) [13]
6. Duodenal acid load exceeds buffering capacity
7. Gastric metaplasia develops in proximal duodenum (adaptation to acid)
8. H. pylori colonizes metaplastic gastric epithelium in duodenum
9. Duodenitis develops
10. Mucosal injury and ulceration result from inflammation and acid exposure

Gastric Ulcer Pathogenesis:

1. H. pylori causes corpus-predominant or pangastritis
2. Gastric atrophy develops over time
3. Reduced acid secretion (most gastric ulcer patients are hypochlorhydric)
4. Mucosal atrophy and impaired defensive mechanisms
5. Ulceration occurs despite low acid due to weakened mucosal resistance

Inflammatory Cascade:

H. pylori infection triggers robust innate and adaptive immune responses:

• Neutrophil infiltration (acute inflammation)
• Lymphocyte and plasma cell infiltration (chronic inflammation)
• Cytokine release: IL-1β, IL-6, IL-8, TNF-α [12]
• Reactive oxygen species generation
• Epithelial cell apoptosis
• Disruption of tight junctions
• Impaired mucus production
• Reduced bicarbonate secretion

NSAID-Induced Ulceration

NSAIDs cause mucosal injury through both systemic (prostaglandin-dependent) and local (prostaglandin-independent) mechanisms. [3]

Exam Detail: Prostaglandin-Dependent Mechanisms (COX Inhibition):

NSAIDs inhibit cyclooxygenase (COX) enzymes, particularly COX-1, which is constitutively expressed in gastric mucosa.

1. COX-1 Inhibition:

   • Reduced prostaglandin E2 (PGE2) synthesis
   • Decreased mucus secretion
   • Decreased bicarbonate secretion
   • Reduced mucosal blood flow
   • Impaired epithelial proliferation and repair
   • Enhanced leukocyte adherence to vascular endothelium

2. COX-2 Role:

   • COX-2 is induced at sites of inflammation but also contributes to ulcer healing
   • Selective COX-2 inhibitors reduce but do not eliminate GI toxicity
   • COX-2 inhibition may delay ulcer healing

Prostaglandin-Independent Mechanisms:

1. Direct topical injury (weak acids):

   • NSAIDs are weak acids that accumulate in epithelial cells
   • Disruption of epithelial cell membranes
   • Uncoupling of oxidative phosphorylation
   • Reduced ATP production
   • Increased epithelial permeability

2. Enterohepatic circulation:

   • Systemic NSAIDs reach gastric mucosa via bloodstream
   • Explains why parenteral/rectal NSAIDs also cause ulcers

3. Neutrophil activation:

   • NSAID-induced increase in neutrophil-endothelial adherence
   • Microvascular injury
   • Ischemia-reperfusion injury

Time Course:

• Acute superficial injury: Within hours of NSAID ingestion
• Chronic ulceration: Develops over weeks to months of regular use
• Adaptation: Partial mucosal adaptation occurs with continued use but protection is incomplete

Other Causes

Zollinger-Ellison Syndrome (Gastrinoma):

• Gastrin-secreting neuroendocrine tumor (usually pancreatic or duodenal)
• Marked gastric acid hypersecretion (basal acid output > 15 mEq/hr)
• Multiple, refractory, or atypically located ulcers
• Associated with MEN-1 syndrome in 20-30% [14]
• Accounts for less than 1% of PUD

Stress-Related Mucosal Disease (SRMD):

• Occurs in critically ill patients (mechanical ventilation, coagulopathy, burns, sepsis)
• Pathogenesis: splanchnic hypoperfusion, mucosal ischemia
• Typically multiple superficial erosions
• Risk reduced by enteral nutrition and stress ulcer prophylaxis
• Clinically significant bleeding in 1-5% of ICU patients [15]

Other Rare Causes:

• Crohn's disease (especially gastroduodenal Crohn's)
• Viral infections (CMV, HSV) in immunocompromised
• Vascular insufficiency (rare)
• Radiation therapy
• Chemotherapy (particularly antimetabolites)

Gastritis Classification

Gastritis represents a heterogeneous group of disorders classified by etiology, histology, and distribution.

Sydney System Classification (1990, Updated 1994): [16]

The Sydney System combines topographical, morphological, and etiological information:

By Distribution:

• Antral-predominant gastritis (associated with duodenal ulcer, H. pylori)
• Corpus-predominant gastritis (associated with gastric ulcer, atrophy)
• Pangastritis (multifocal atrophic gastritis, cancer risk)

By Etiology:

• H. pylori gastritis (most common)
• Autoimmune gastritis (pernicious anemia)
• Chemical/reactive gastritis (NSAIDs, bile reflux)
• Other infectious (rare: CMV, HSV, fungi)
• Granulomatous (Crohn's, sarcoidosis)
• Eosinophilic gastritis
• Lymphocytic gastritis

By Histology:

• Acute gastritis (neutrophilic infiltration)
• Chronic gastritis (lymphoplasmacytic infiltration)
• Atrophic gastritis (loss of appropriate glands)
• Metaplasia (intestinal metaplasia—cancer risk)

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Clinical Presentation

Symptoms

The clinical presentation of gastritis and PUD varies from asymptomatic disease to life-threatening complications. Approximately 20-30% of ulcers are clinically silent, discovered only when complications develop. [17]

Dyspepsia (Predominant Symptom Complex):

Classic Teaching (Historical Significance):

• Duodenal ulcer: "Pain 2-3 hours after meals, relieved by food"—this pattern occurs in less than 50% of cases
• Gastric ulcer: "Pain shortly after eating, worsened by food"—inconsistent finding
• Modern perspective: Symptom patterns have poor sensitivity and specificity for differentiating ulcer types or distinguishing from functional dyspepsia

Complicated PUD Presentations:

Physical Examination

The physical examination in uncomplicated PUD is typically unremarkable or reveals only mild epigastric tenderness.

General Inspection:

• Pallor (anemia from chronic blood loss)
• Cachexia (if malignancy)
• Signs of chronic liver disease (portal hypertensive gastropathy mimics)

Abdominal Examination:

Cardiovascular Assessment:

• Tachycardia > 100 bpm: suggests significant bleeding
• Orthostatic hypotension (≥20 mmHg systolic drop or ≥10 bpm HR increase): 10-20% volume loss
• Hypotension: ≥40% volume loss, severe hemorrhage

Rectal Examination:

• Melena: black, tarry, sticky, foul-smelling stools (> 50 mL blood loss)
• Positive fecal occult blood test: chronic low-grade bleeding

Red Flags ("Alarm Features")

The presence of alarm features mandates urgent investigation to exclude malignancy or complications:

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Differential Diagnosis

Dyspepsia is a nonspecific symptom complex with numerous causes beyond PUD.

Structural/Organic Causes

Functional Disorders

Vascular Causes

Medication/Toxin-Related

• NSAIDs/aspirin: Detailed medication history essential
• Bisphosphonates: Esophagitis, gastritis
• Potassium supplements: Mucosal injury
• Iron supplements: Gastric irritation
• Alcohol: Acute gastritis, chronic pancreatitis

Metabolic/Systemic

• Diabetic gastroparesis: Nausea, vomiting, postprandial fullness, diabetes history
• Hypercalcemia: Increased gastrin secretion, constipation
• Addison's disease: Hyperpigmentation, hypotension
• Thyroid disorders: Associated symptoms

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Diagnostic Approach

Clinical Assessment

Diagnosis begins with careful history and physical examination, risk factor assessment (H. pylori risk, NSAID use), and identification of alarm features.

Initial Risk Stratification:

1. Age less than 55 years, no alarm features, no NSAID use:

   • Test-and-treat strategy for H. pylori OR
   • Empirical PPI trial × 4-8 weeks [18]
   • Endoscopy if persistent symptoms despite treatment

2. Age ≥55 years OR alarm features present:

   • Urgent upper endoscopy (within 2 weeks) [18]

3. NSAID-associated symptoms:

   • Stop NSAID if feasible
   • PPI therapy
   • Consider endoscopy if severe or persistent symptoms

Laboratory Investigations

Initial Laboratory Tests:

In Acute Upper GI Bleeding:

• Type and crossmatch blood
• BUN:creatinine ratio > 20 suggests upper GI source (blood protein absorption)

Helicobacter pylori Testing

H. pylori testing should be performed in all patients with confirmed or suspected PUD. [8]

Non-Invasive Tests:

Invasive Tests (Endoscopy-Based):

Key Considerations:

• PPI effect: PPIs reduce H. pylori density, decreasing sensitivity of UBT, RUT, and histology. Discontinue PPIs 2 weeks before testing (4 weeks for histology). [8]
• Antibiotics: Discontinue 4 weeks before testing
• Test of cure: Recommended ≥4 weeks after completing eradication therapy, using UBT or stool antigen (NOT serology) [8]
• Discordant results: If high clinical suspicion and negative non-invasive test, proceed to endoscopy with biopsy

Upper Gastrointestinal Endoscopy (EGD)

Esophagogastroduodenoscopy is the gold standard for diagnosing PUD, assessing severity, obtaining biopsies, and providing therapy.

Indications for EGD:

Endoscopic Findings:

Ulcer Characteristics:

• Size: Measured in millimeters; > 2 cm associated with higher rebleeding risk
• Location: Posterior duodenal bulb ulcers at risk for gastroduodenal artery bleeding
• Depth: Penetrating ulcers may involve adjacent structures (pancreas, liver)
• Edges: Raised, irregular edges suggest malignancy
• Base: Clean base (low risk), adherent clot, visible vessel (high risk), active bleeding

Forrest Classification (Peptic Ulcer Bleeding): [23]

Biopsy Strategy:

• Gastric ulcer: Minimum 6-8 biopsies from ulcer margin to exclude malignancy (3-5% of gastric ulcers are malignant) [22]
• Duodenal ulcer: Biopsy not routinely required (malignancy extremely rare)
• H. pylori testing: Biopsies from antrum and corpus for RUT and/or histology

Imaging

Abdominal X-Ray (Erect Chest X-Ray):

CT Abdomen/Pelvis with IV Contrast:

• Primary role: Evaluation of suspected perforation or penetration
• Sensitivity for perforation: > 90% (superior to X-ray) [24]
• Findings: Extraluminal air, abscess, thickened gastric/duodenal wall, inflammatory changes
• Advantages: Identifies site of perforation, assesses extent of contamination, guides surgical planning

Upper GI Series (Barium Study):

• Historical role: Largely replaced by endoscopy
• Current indications: Very limited; patients unable to undergo endoscopy
• Sensitivity: 70-80% for ulcer detection
• Limitations: Cannot biopsy, cannot differentiate benign from malignant, cannot provide therapy

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Classification and Staging

Anatomical Classification

By Location:

Johnson Classification of Gastric Ulcers:

Severity Classification

By Complications:

Risk Stratification for Upper GI Bleeding

Glasgow-Blatchford Score (GBS): [25]

Pre-endoscopy risk score to identify patients at low risk who may be suitable for outpatient management.

Interpretation:

• GBS = 0: Very low risk; consider outpatient management (sensitivity 99% for need for intervention) [25]
• GBS ≥1: Admission recommended
• GBS ≥12: High risk; intensive monitoring, early endoscopy

Rockall Score: [26]

Post-endoscopy score predicting mortality and rebleeding risk.

Interpretation:

• Score 0-2: Low risk (mortality less than 0.2%, rebleeding less than 5%)
• Score 3-4: Moderate risk (mortality 5%, rebleeding 11%)
• Score ≥5: High risk (mortality 11-40%, rebleeding 25-40%)

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Management

Management of gastritis and PUD centers on acid suppression, H. pylori eradication, NSAID cessation, and complication management.

General Principles

1. Acid suppression: Cornerstone of therapy to allow healing
2. H. pylori eradication: Essential if infection present
3. NSAID cessation: Stop if possible; if not, use lowest dose + gastroprotection
4. Lifestyle modifications: Smoking cessation, alcohol moderation
5. Complication management: Specific strategies for bleeding, perforation, obstruction
6. Follow-up: Ensure healing (especially gastric ulcers), confirm H. pylori eradication

Acid Suppression Therapy

Proton Pump Inhibitors (PPIs):

PPIs irreversibly inhibit H+/K+-ATPase on parietal cells, providing superior acid suppression compared to H2-receptor antagonists.

Efficacy:

• Duodenal ulcer healing: 90-95% at 4 weeks [27]
• Gastric ulcer healing: 80-90% at 8 weeks [27]
• Symptom relief: 70-80% within 1 week

Duration:

• Uncomplicated duodenal ulcer: 4-6 weeks
• Uncomplicated gastric ulcer: 8-12 weeks
• NSAID-associated ulcer: 8-12 weeks
• Giant ulcer (> 2 cm): 12 weeks
• Maintenance therapy: Not routinely recommended after H. pylori eradication; consider in high-risk patients (recurrent bleeding, cannot stop NSAIDs)

H2-Receptor Antagonists (H2RAs):

Less effective than PPIs; largely relegated to adjunctive role.

Current Role: Nocturnal acid suppression if inadequate PPI response (controversial), GERD maintenance

Antacids and Mucosal Protective Agents:

Helicobacter pylori Eradication Therapy

Successful eradication reduces ulcer recurrence from 60-80% to less than 10% annually. [8] Eradication rates have declined globally due to increasing antibiotic resistance, particularly clarithromycin (> 15-20% resistance in many regions). [28]

First-Line Regimens:

1. Bismuth-Based Quadruple Therapy (Preferred in High Clarithromycin Resistance Areas > 15%): [8,28]

• Eradication rate: 85-90%
• Advantages: Effective despite clarithromycin resistance
• Disadvantages: QID dosing, pill burden (12-14 pills/day), side effects

2. Clarithromycin-Based Triple Therapy (If Local Clarithromycin Resistance less than 15%): [8]

• Eradication rate: 70-85% (declining due to resistance)
• Note: Inferior to quadruple therapy in most regions; no longer recommended first-line by ACG [28]

3. Concomitant Therapy (Non-Bismuth Quadruple): [28]

• Eradication rate: 85-90%
• Advantages: Effective in clarithromycin resistance, BID dosing
• Disadvantages: Pill burden, cost

4. Levofloxacin-Based Triple Therapy (Alternative First-Line): [28]

• Eradication rate: 75-85%
• Concerns: Fluoroquinolone resistance (5-15% in many regions), FDA black box warnings (tendon rupture, C. difficile, QT prolongation)

Special Considerations:

Penicillin Allergy:

• Replace amoxicillin with metronidazole in triple therapy
• Use bismuth quadruple therapy (tetracycline acceptable in penicillin allergy)

Second-Line (Salvage) Therapy After First-Line Failure:

Option 1: Bismuth Quadruple Therapy (if not used first-line)

Option 2: Levofloxacin-Based Triple Therapy (if not used first-line)

Option 3: High-Dose Dual PPI-Amoxicillin Therapy:

• PPI (high dose) BID + Amoxicillin 750-1000 mg TID × 14 days
• Eradication ~70%

Third-Line (Rescue) Therapy:

• Culture and sensitivity-guided therapy (gold standard)
• Rifabutin-based therapy (off-label, reserved for multiple failures)

Test of Cure:

• Recommended: For all patients [8]
• Timing: ≥4 weeks after completing eradication therapy
• Method: Urea breath test OR stool antigen test (NOT serology)
• PPI: Discontinue 2 weeks before test

Factors Affecting Eradication:

NSAID-Associated Ulcer Management

Step 1: Assess Need for NSAID:

• Discontinue NSAID if possible (most important intervention)
• Ulcer healing rates: 80-90% at 8 weeks off NSAIDs vs. 60-70% continued NSAIDs [29]

Step 2: PPI Therapy:

• Standard-dose PPI × 8-12 weeks
• Healing rates with PPI despite continued NSAIDs: 70-80% [29]

Step 3: Risk Stratification for Future NSAID Use:

GI Risk Factors for NSAID-Induced Ulcer Complications:

• Age > 65 years
• Prior ulcer or ulcer complication
• High-dose NSAID or multiple NSAIDs
• Concurrent aspirin (including low-dose)
• Concurrent anticoagulation
• Concurrent corticosteroids
• H. pylori infection (test and treat)

Step 4: COX-2 Selective Inhibitors:

Step 5: H. pylori Testing and Eradication:

• Test all NSAID users with ulcers [8]
• Eradication reduces ulcer recurrence in NSAID users
• Eradication alone does NOT prevent ulcers in chronic NSAID users (PPI still required)

Step 6: Alternatives to NSAIDs:

• Acetaminophen (limited anti-inflammatory effect)
• Topical NSAIDs (reduced systemic absorption)
• Physical therapy, exercise
• Intra-articular corticosteroids

Management of Specific Complications

Upper Gastrointestinal Bleeding

Bleeding ulcers account for 50-60% of upper GI bleeding cases. [19]

Initial Resuscitation:

1. Airway protection: Consider intubation if altered mentation, massive hematemesis
2. IV access: Two large-bore IVs (18-gauge or larger)
3. Fluid resuscitation: Crystalloid (normal saline, lactated Ringer's)
4. Blood transfusion:
   • Restrictive strategy: Transfuse if Hgb less than 7 g/dL (target 7-9 g/dL) [31]
   • Liberal strategy: Consider if Hgb less than 8-9 g/dL in high-risk (active CAD, hemodynamic instability)
   • Restrictive strategy associated with lower rebleeding and mortality [31]
5. Correct coagulopathy:
   • INR > 2.5: Vitamin K + prothrombin complex concentrate (PCC) or FFP
   • Platelets less than 50,000: Platelet transfusion (target > 50,000)
6. Anticoagulation/antiplatelet management:
   • Hold anticoagulation initially
   • Low-dose aspirin: Consider continuing if high thrombotic risk (recent ACS/stent)
   • Resume anticoagulation 72 hours post-hemostasis if high thrombotic risk

Pharmacological Therapy:

High-Dose IV PPI Protocol: [19]

• Regimen: Pantoprazole or omeprazole 80 mg IV bolus, followed by 8 mg/hour continuous infusion × 72 hours
• Mechanism: Maintains intragastric pH > 6, optimizes clot stability
• Benefits: Reduces rebleeding (10.6% vs. 17.3%), need for surgery, mortality (PMID: 24160923)
• Transition: Oral PPI BID after 72 hours, then daily

Prokinetic Agents (Erythromycin):

• Dose: Erythromycin 250 mg IV 30-60 minutes pre-endoscopy
• Mechanism: Motilin receptor agonist; promotes gastric emptying
• Benefit: Improves endoscopic visualization, reduces need for repeat endoscopy
• Controversial: Not universally recommended

Somatostatin Analogs:

• Octreotide: Reserved for variceal bleeding (not peptic ulcer bleeding)

Endoscopic Therapy:

Timing: Urgent endoscopy within 24 hours [19]

Hemostatic Techniques:

Indications for Endoscopic Therapy (Based on Forrest Classification):

• Forrest Ia, Ib (active bleeding): Definite indication
• Forrest IIa (visible vessel): Definite indication
• Forrest IIb (adherent clot): Consider therapy vs. medical management
• Forrest IIc, III: Medical management (PPI) alone

Surgical Intervention:

Indications:

• Refractory bleeding (failure of two endoscopic attempts)
• Hemodynamic instability despite resuscitation and endoscopic therapy
• Transfusion requirement > 6 units in 24 hours
• Recurrent bleeding after successful endoscopic hemostasis (controversial; consider repeat endoscopy)

Procedures:

• Oversewing of bleeding vessel (duodenal or gastric ulcer)
• Vagotomy and pyloroplasty (duodenal ulcer, historically)
• Partial gastrectomy (gastric ulcer)

Angiographic Embolization:

• Alternative to surgery in high-risk surgical candidates
• Embolize gastroduodenal artery (duodenal ulcer) or left gastric artery (gastric ulcer)
• Success rate: 75-85%
• Complications: Ischemia, rebleeding

Disposition:

• Admit to ICU: Hemodynamic instability, active bleeding, high Rockall score (≥5)
• Admit to ward: Most patients post-endoscopy, intermediate risk
• Discharge: Stable, GBS = 0, low-risk endoscopic findings (Forrest IIc/III)

Perforated Peptic Ulcer

Perforation occurs in 2-10% of PUD cases, with mortality 10-25% (highest in elderly, delayed presentation > 24 hours). [7]

Clinical Presentation:

• Sudden severe epigastric pain
• Board-like rigidity, diffuse peritonitis
• Shoulder pain (diaphragmatic irritation)
• Tachycardia, hypotension (septic shock if delayed)

Diagnosis:

• Erect CXR: Pneumoperitoneum in 70-80% [24]
• CT abdomen/pelvis: Sensitivity > 90% [24]

Initial Management:

1. Resuscitation: IV fluids, broad-spectrum antibiotics
2. NPO: Bowel rest
3. NG tube: Gastric decompression
4. IV PPI: High-dose
5. Broad-spectrum antibiotics:
   • Piperacillin-tazobactam 4.5 g IV q6h OR
   • Ceftriaxone 2 g IV daily + metronidazole 500 mg IV q8h

Surgical Management:

Indications for Surgery (Most Cases):

• Generalized peritonitis
• Hemodynamic instability
• Large perforation (> 1 cm)
• Delayed presentation (> 24 hours)

Operative Options:

• Laparoscopic repair (preferred if expertise available): Graham patch (omental patch closure)
• Open repair: Omental patch, primary closure + omental reinforcement
• Definitive procedure (rare, historical): Vagotomy, pyloroplasty, partial gastrectomy

Non-Operative Management (Selected Patients):

Inclusion Criteria:

• Localized perforation (no generalized peritonitis)
• Hemodynamically stable
• Small perforation (less than 1 cm)
• Early presentation (less than 12 hours)
• CT shows contained perforation

Protocol:

• NPO
• NG decompression
• IV fluids
• Broad-spectrum IV antibiotics
• High-dose IV PPI
• Serial abdominal exams
• Repeat imaging if clinical deterioration

Success Rate: 70-80% in carefully selected patients [32]

Post-Operative Care:

• Continue IV PPI
• H. pylori testing and eradication
• EGD 6-8 weeks post-discharge to confirm healing

Gastric Outlet Obstruction (GOO)

GOO occurs in ~2% of PUD cases, due to chronic scarring or acute edema/inflammation of pyloric channel or duodenum. [6]

Clinical Presentation:

• Postprandial fullness, early satiety
• Nausea, vomiting (often projectile, undigested food)
• Weight loss
• Succussion splash on examination
• Hypochloremic, hypokalemic metabolic alkalosis (chronic vomiting)

Diagnosis:

• EGD: Direct visualization of obstruction, assess for malignancy
• CT abdomen: Gastric distension, thickened pylorus/duodenum
• Upper GI series: Delayed gastric emptying (if endoscopy not feasible)

Initial Management:

1. NG decompression: Continuous suction
2. IV fluids: Correct dehydration, electrolyte abnormalities
3. IV PPI: High-dose
4. Nutritional support: Parenteral nutrition if prolonged

Definitive Management:

Medical/Endoscopic:

• Endoscopic balloon dilation: For benign strictures
  • "Success rate: 70-80%"
  • Multiple sessions often required
  • "Perforation risk: 2-3%"

Surgical:

• Indications: Failed medical/endoscopic therapy, malignancy, refractory obstruction
• Procedures:
  • Vagotomy and antrectomy (gastrojejunostomy)
  • Gastrojejunostomy alone (bypass)
  • Highly selective vagotomy + pyloroplasty

Special Populations

Elderly (≥65 Years):

• Increased ulcer prevalence due to NSAIDs, anticoagulation
• Higher complication rates (bleeding, perforation)
• Often asymptomatic until complication
• Lower threshold for endoscopy
• Adjust drug doses for renal function

Pregnancy:

• PUD uncommon during pregnancy (protective effect of progesterone, reduced acid)
• PPI: Category B (omeprazole, pantoprazole); generally safe
• H. pylori eradication: Defer until postpartum (amoxicillin + clarithromycin contraindicated)
• Endoscopy: Safe if indicated; defer elective procedures to second trimester

Anticoagulation/Antiplatelet Therapy:

• Increased bleeding risk (RR 2-3) [10]
• Consider PPI prophylaxis in high-risk patients
• Balance thrombotic vs. bleeding risk when managing acute bleeding
• Resume anticoagulation 72 hours post-hemostasis if high thrombotic risk (mechanical valve, recent VTE, ACS)

ICU Patients (Stress Ulcer Prophylaxis):

• High-risk criteria: Mechanical ventilation > 48 hours, coagulopathy
• Prophylaxis: PPI or H2RA
• Reduce risk: Enteral nutrition
• Discontinue: Upon ICU discharge or resolution of risk factors

Refractory Ulcers:

Definition: Ulcer failing to heal after 8-12 weeks of PPI therapy

Causes:

• Persistent H. pylori (failed eradication)
• Continued NSAID use
• Non-compliance with PPI
• Smoking
• Zollinger-Ellison syndrome
• Gastric malignancy (especially gastric ulcer)
• Cameron ulcers (hiatal hernia)
• Other rare causes: Crohn's disease, sarcoidosis, lymphoma

Evaluation:

• Confirm H. pylori status (repeat testing)
• Review medication adherence
• Assess NSAID/aspirin use (including OTC)
• Consider fasting gastrin level (Zollinger-Ellison)
• Repeat endoscopy with extensive biopsies (rule out malignancy)
• Increase PPI dose (BID dosing)

Lifestyle and Dietary Modifications

Smoking Cessation:

• Impact: Smoking impairs healing, increases recurrence risk (RR 2) [11]
• Mechanism: Reduced mucosal blood flow, impaired prostaglandin synthesis, increased acid secretion
• Recommendation: Strongly encourage cessation; offer pharmacotherapy/counseling

Alcohol Moderation:

• Moderate alcohol (1-2 drinks/day): No clear association with PUD
• Heavy alcohol (> 3 drinks/day): Increases risk (RR 1.5-2) [6]
• Recommendation: Limit to moderate intake

Dietary Modifications:

• No evidence for restrictive diets (bland diet, milk)
• Avoid foods that exacerbate symptoms (individual variation)
• Small, frequent meals if early satiety/nausea
• Avoid late-night eating (nocturnal acid secretion)

Stress Reduction:

• Chronic psychological stress may impair healing
• Consider stress management techniques (limited evidence)

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Prognosis and Outcomes

Ulcer Healing Rates

Recurrence Rates

Complication Outcomes

Bleeding:

• Initial hemostasis: 85-95% with endoscopic therapy [19]
• Rebleeding: 10-20% within 72 hours [19]
• Mortality: 5-10% overall; 15-25% if rebleeding occurs [4]
• Predictors of poor outcome: Age > 65, comorbidities, hemodynamic instability, rebleeding

Perforation:

• Mortality: 10-25% [7]
• Predictors of mortality: Age > 65, delayed presentation (> 24 hours), shock, comorbidities
• Post-operative complications: Abscess, wound infection, prolonged ileus (10-20%)

Gastric Outlet Obstruction:

• Medical/endoscopic success: 70-80%
• Surgical success: > 90%
• Recurrence after balloon dilation: 20-30%

Long-Term Outcomes After H. pylori Eradication

• Ulcer recurrence: Reduced from 60-80% to less than 10% [8]
• Gastric cancer risk: Reduced if eradicated before atrophic gastritis/metaplasia develops [33]
• MALT lymphoma: 60-80% regression with eradication alone [34]
• Dyspepsia symptoms: 5-10% persistent despite eradication (consider functional dyspepsia)

Malignancy Risk

Gastric Ulcers:

• 3-5% are malignant at presentation [22]
• Repeat endoscopy with biopsy at 8-12 weeks mandatory to confirm healing and exclude malignancy

Duodenal Ulcers:

• Malignancy extremely rare (less than 0.1%)
• Routine follow-up endoscopy not required

H. pylori and Gastric Cancer:

• H. pylori is Class I carcinogen (WHO)
• Increases gastric adenocarcinoma risk 3-6 fold [33]
• Eradication reduces cancer risk if performed before irreversible atrophic changes

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Prevention and Screening

Primary Prevention

H. pylori:

• No universal screening recommendations in asymptomatic individuals
• Test-and-treat strategy appropriate in high-risk groups:
  • Family history of gastric cancer
  • Prior gastric cancer or MALT lymphoma
  • Beginning long-term NSAID therapy
  • Before initiating antiplatelet therapy (low-dose aspirin)
  • Unexplained iron-deficiency anemia

NSAID Users:

Aspirin Users (Cardiovascular Prophylaxis):

• Low GI risk: Aspirin alone
• Moderate GI risk: Aspirin + PPI
• High GI risk (prior ulcer bleeding): Avoid aspirin if possible; if required: aspirin + PPI (reduces rebleeding from 9% to 0.7% over 6 months) [35]

Stress Ulcer Prophylaxis (SUP)

High-Risk ICU Patients:

Indications (≥1 of the following):

• Mechanical ventilation > 48 hours
• Coagulopathy (platelets less than 50,000, INR > 1.5, PTT > 2× control)

Moderate Risk (Consider SUP if ≥2):

• ICU stay > 1 week
• Occult GI bleeding ≥6 days
• High-dose corticosteroids (> 250 mg hydrocortisone/day)
• Severe burns (> 35% BSA)
• Traumatic brain or spinal cord injury
• Acute kidney injury or liver failure

Prophylaxis Options:

• PPI (pantoprazole 40 mg IV daily): Preferred
• H2RA (famotidine 20 mg IV BID): Alternative
• Enteral nutrition: Protective; reduces SUP need

Discontinuation: Transition to oral intake, extubation, or ICU discharge

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Key Guidelines and Evidence

Major Society Guidelines

Landmark Trials and Evidence

H. pylori Eradication:

• Meta-analysis (Cochrane 2020): Eradication reduces ulcer recurrence from 67% to 6% at 12 months (PMID: 32880007)

PPI in Bleeding Ulcers:

• Lau et al. (NEJM 2000): High-dose IV PPI post-endoscopy reduced rebleeding (6.7% vs. 13.6%) (PMID: 10793165)

Transfusion Strategy:

• Villanueva et al. (NEJM 2013): Restrictive transfusion (Hgb less than 7) superior to liberal (Hgb less than 9) in upper GI bleeding; mortality 5% vs. 9% (PMID: 23281973)

COX-2 Inhibitors:

• VIGOR trial: Rofecoxib reduced ulcer complications by 54% vs. naproxen (PMID: 11117777)
• CLASS trial: Celecoxib reduced ulcer complications vs. NSAIDs (PMID: 10647012)

Endoscopic Therapy:

• Calvet et al. (Gastroenterology 2004): Combination therapy (epinephrine + thermal/clips) superior to epinephrine alone (PMID: 15188162)

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Common Exam Questions and Viva Points

Opening Statement

Viva Point: "Peptic ulcer disease encompasses gastric and duodenal ulcers, which are mucosal breaks extending through the muscularis mucosae. The condition affects 5-10% of the population over their lifetime. The pathogenesis centers on an imbalance between aggressive factors—primarily Helicobacter pylori infection and NSAID use—and protective mucosal mechanisms. H. pylori accounts for 70-80% of duodenal ulcers and 50-60% of gastric ulcers, while NSAIDs are the predominant cause of H. pylori-negative ulcers. Complications, including hemorrhage in 15-20% and perforation in 2-10%, contribute significantly to morbidity and mortality. Modern management focuses on acid suppression with proton pump inhibitors, H. pylori eradication when present, and NSAID cessation when feasible."

High-Yield Exam Topics

1. What are the causes of peptic ulcer disease?

"The two primary causes are Helicobacter pylori infection and NSAID use, accounting for over 90% of cases. H. pylori causes 70-80% of duodenal ulcers and 50-60% of gastric ulcers. NSAIDs are the leading cause of H. pylori-negative ulcers, particularly in elderly patients. Rare causes include Zollinger-Ellison syndrome (gastrin-secreting tumor causing acid hypersecretion), stress-related mucosal disease in critically ill patients, and very rarely Crohn's disease, viral infections in immunocompromised hosts, or vascular insufficiency."

2. Describe the pathophysiology of H. pylori-induced peptic ulcer disease.

"Helicobacter pylori is a spiral gram-negative bacterium that colonizes gastric mucosa. Its virulence factors—including urease (neutralizes acid, enabling survival), CagA (disrupts epithelial integrity, activates inflammation), and VacA (cytotoxin causing cell damage)—trigger chronic inflammation. In duodenal ulcer, antral-predominant gastritis leads to reduced somatostatin and increased gastrin secretion, resulting in acid hypersecretion. Excess duodenal acid load induces gastric metaplasia, which H. pylori then colonizes, causing duodenitis and ulceration. In gastric ulcer, corpus-predominant gastritis causes atrophy and reduced acid secretion; ulceration results from weakened mucosal defenses despite hypochlorhydria."

3. How would you investigate a patient with dyspepsia?

"Investigation depends on age and alarm features. Patients ≥55 years or those with alarm features—such as weight loss, dysphagia, persistent vomiting, hematemesis, or anemia—require urgent endoscopy within 2 weeks to exclude malignancy. For patients less than 55 without alarm features, options include a test-and-treat strategy for H. pylori using non-invasive tests like urea breath test or stool antigen, or empirical PPI therapy for 4-8 weeks. If symptoms persist despite treatment, endoscopy is indicated. NSAID use should be assessed and discontinued if present."

4. What is your management approach to a bleeding peptic ulcer?

"Management follows an ABCDE approach. Initial resuscitation includes two large-bore IVs, crystalloid fluids, and restrictive blood transfusion targeting hemoglobin 7-9 g/dL unless high cardiac risk. High-dose IV PPI—pantoprazole 80 mg bolus followed by 8 mg/hour infusion for 72 hours—should be initiated immediately. Urgent endoscopy within 24 hours is essential for diagnosis and hemostatic therapy. Endoscopic treatment uses combination therapy: epinephrine injection plus thermal coagulation or hemoclips, achieving > 95% initial hemostasis. Surgery or angiographic embolization is reserved for refractory bleeding after failed endoscopic attempts. Post-procedure, H. pylori testing and eradication are mandatory, along with NSAID cessation."

5. Describe the treatment regimens for H. pylori eradication.

"First-line therapy is bismuth-based quadruple therapy for 14 days: standard-dose PPI twice daily, bismuth subsalicylate 524 mg four times daily, metronidazole 500 mg three to four times daily, and tetracycline 500 mg four times daily. This achieves 85-90% eradication and is effective despite clarithromycin resistance. An alternative is concomitant non-bismuth quadruple therapy: PPI twice daily with clarithromycin 500 mg, amoxicillin 1000 mg, and metronidazole 500 mg, all twice daily for 14 days. Clarithromycin-based triple therapy—PPI, clarithromycin, and amoxicillin—is no longer recommended first-line due to resistance. Test of cure using urea breath test or stool antigen is recommended ≥4 weeks post-treatment."

6. What are the indications for surgery in peptic ulcer disease?

"Surgical indications include perforated ulcer with generalized peritonitis (most common), refractory bleeding after failed endoscopic hemostasis (typically two attempts), hemodynamic instability despite resuscitation and endoscopic therapy, or recurrent bleeding. Gastric outlet obstruction refractory to medical and endoscopic management is another indication. Historically, intractable ulcer pain despite medical therapy was an indication, but this is now rare with effective PPI therapy and H. pylori eradication. For perforation, laparoscopic or open omental patch repair is standard. For bleeding, oversewing of the vessel with possible vagotomy and pyloroplasty or partial gastrectomy may be performed."

7. What is the difference between gastric and duodenal ulcers?

"Duodenal ulcers are three times more common, typically occur in younger adults (30-55 years), have male predominance (2-3:1), are associated with H. pylori in 70-80%, and often present with pain 2-3 hours postprandially or nocturnally, relieved by food. They occur in the setting of increased acid secretion. Gastric ulcers affect older individuals (55-70 years), have equal sex distribution, are associated with H. pylori in only 50-60% (higher NSAID contribution), present with pain shortly after eating or no clear pattern, and occur with normal or low acid secretion. Critically, 3-5% of gastric ulcers are malignant, mandating repeat endoscopy at 8-12 weeks to confirm healing and exclude cancer, whereas duodenal ulcer malignancy is exceptionally rare."

8. How do you prevent NSAID-induced ulcers?

"Prevention is risk-stratified. Low-risk patients (no risk factors) require no prophylaxis. Moderate-risk patients (age > 65 or 1-2 risk factors) should receive either a COX-2 selective inhibitor or a non-selective NSAID plus PPI. High-risk patients (prior ulcer or bleeding, multiple risk factors) require both a COX-2 inhibitor and PPI. Patients with recent ulcer complications should avoid NSAIDs entirely; if essential, COX-2 plus PPI with close monitoring is required. All NSAID users should be tested for H. pylori and treated if positive, as eradication reduces but does not eliminate ulcer risk. The lowest effective NSAID dose for the shortest duration should always be used."

Common Mistakes

❌ Failing to perform test of cure after H. pylori eradication: Essential to confirm success

❌ Using serology for H. pylori test of cure: Serology remains positive post-eradication; use UBT or stool antigen

❌ Omitting repeat endoscopy for gastric ulcers: 3-5% are malignant; repeat EGD at 8-12 weeks mandatory

❌ Continuing clarithromycin triple therapy as first-line: Resistance now exceeds 15% in most regions; bismuth quadruple therapy preferred

❌ Liberal transfusion strategy in upper GI bleeding: Restrictive strategy (Hgb less than 7) improves outcomes

❌ Epinephrine injection monotherapy: Combination with thermal coagulation or clips is superior

❌ Discontinuing aspirin indefinitely after bleeding: Balance thrombotic risk; may resume low-dose aspirin with PPI after hemostasis in high-risk cardiac patients

❌ Ignoring cardiovascular risk when prescribing COX-2 inhibitors: COX-2 inhibitors may increase CV events; avoid in high CV risk

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