Peptic Ulcer Disease and Gastritis

1. THE 2-MINUTE PHYSIOLOGY (Rapid Pathophysiology)

• The Core Mechanism: Strictly speaking, gastritis is a histologic diagnosis defined by gastric mucosal injury accompanied by active inflammation. Gastropathy refers to mucosal injury without inflammation. If left untreated, both can progress to Peptic Ulcer Disease (PUD), characterized by deep mucosal ulcerations extending into the stomach or proximal duodenum.
• Cellular/Mechanical Breakdown: The underlying pathophysiology is a breakdown of the protective mucosal barrier against acidic gut flora and gastric acid. This barrier failure is heavily driven by the use of NSAIDs, corticosteroids, immunosuppressants, and Helicobacter pylori infection.
• Circadian Acid Surge: Peak gastric acid secretion occurs during the early morning hours (between 1:00 AM and 3:00 AM), which mechanically irritates the ulcerated mucosa and classically awakens the patient from sleep.
• Catastrophic Progression: As the ulcer burrows deeper through the bowel wall, it can erode into submucosal blood vessels causing life-threatening upper gastrointestinal (GI) hemorrhage, or breach the full thickness of the wall causing a perforation that spills acidic contents and air into the sterile peritoneum.

2. THE BEDSIDE ACTION PLAN (Rapid ER Management)

• Uncomplicated Cases (The "Test and Treat" Strategy): For stable patients with simple dyspepsia, initiate first-line non-eradication therapy with an oral Proton Pump Inhibitor (PPI) or H2 receptor antagonist, and provide liquid antacids for breakthrough pain. You may utilize a urea breath test in the ED to identify H. pylori before referring the patient for outpatient antibacterial therapy.
• For Acute Upper GI Bleeding: Obtain immediate large-bore IV access. Initiate an intravenous Proton Pump Inhibitor (PPI); PPI administration has been proven to definitively decrease rebleeding rates, the need for surgery, and overall mortality in acute upper GI bleeds.
• For Suspected Perforation:
• Resuscitation: Keep the patient strictly NPO. Provide immediate IV fluid resuscitation with 0.9% normal saline.
• Medications: Administer IV analgesia (titrated IV morphine) and an antiemetic (e.g., slow IV metoclopramide 10 mg).
• Antibiotics: Initiate broad-spectrum IV antibiotics (e.g., cefotaxime 1g) to cover for peritoneal soilage.
• Consultation: Obtain an emergent surgical consultation.

3. THE DIAGNOSTIC GRID (Differential Diagnosis & Workup)

• "Can't-Miss" Mimics:
• Acute Coronary Syndrome / Acute Myocardial Infarction (AMI)
• Biliary Colic / Acute Cholecystitis
• Acute Pancreatitis
• Aortic Dissection
• Prioritized Diagnostic Workup:
• ECG & Troponin: Mandatory in older or high-risk adults to ensure the epigastric symptoms do not reflect an AMI or atypical ischemic equivalent sharing the same afferent neural pathways.
• Laboratory Panel: Order a Complete Blood Count (CBC) to screen for occult anemia (with an elevated WBC count typically seen in perforation), comprehensive metabolic panel, and coagulation studies. Check Lipase and Liver Function Tests (LFTs) to rule out pancreaticobiliary mimics.
• The Bleeding Biomarker: Calculate the BUN-to-Creatinine ratio. A BUN:Creatinine ratio > 30 strongly suggests an upper GI source of bleeding rather than lower GI.

4. THE VISUAL BOARD (ECG / POCUS / Imaging)

• Chest Radiograph (CXR): Obtain an upright/erect CXR immediately if perforation is suspected. Scrutinize the film for pneumoperitoneum (free gas under the diaphragm). This classic finding is visible in approximately 75% of patients with a perforated peptic ulcer.
• Computed Tomography (CT): If the upright CXR is negative but clinical suspicion for perforation remains high, the gold-standard next step is a contrast-enhanced CT scan of the abdomen.
• ECG: Scrutinize for inferior ST-segment elevation or hyperacute T waves to rule out cardiac ischemia masquerading as dyspepsia.

5. THE SCORING MATRIX (Risk Stratification & Guidelines)

• Alarm Features Trigger: Clinical guidelines mandate immediate referral for definitive diagnosis (endoscopy) if "Alarm Features" are present. These include:
• Unintentional weight loss
• Signs of active upper GI bleeding (hematemesis or melena)
• Intractable vomiting
• Features suggesting malignancy
• Disposition Cutoffs:
• Patients with hemodynamic instability, intractable pain, complications (bleeding, obstruction, perforation), or high-risk "alarm features" require early specialist consultation (GI/Surgery) and hospital admission.
• Patients with uncomplicated symptoms and normal vital signs may be safely discharged with acid-suppressive therapy (PPI) and prompt primary care follow-up.

6. THE DANGER ZONE (Pitfalls & Critical Actions)

• Cognitive Trap (Premature Closure on "Reflux"): Assuming that epigastric burning in an adult is simply gastritis without evaluating the heart. Correction: PUD and cardiac ischemia share afferent neural pathways; an ECG must be performed on at-risk patients.
• Cognitive Trap (The Reassuring CXR): Ruling out a perforated ulcer simply because the upright CXR shows no free air. Correction: Upright CXRs miss up to 25% of perforations. You must proceed to a contrast CT scan if your clinical suspicion remains high.
• Critical Action (Medication Reconciliation): Failing to identify the root cause of the bleeding. You must specifically ask about the use of over-the-counter NSAIDs, aspirin, and prescribed steroids or anticoagulants, which precipitate the disease and worsen bleeding.

7. MCQ MASTERCLASS (Written Exam Tips)

• Classic Presentation Buzzwords: A patient "awakened from sleep at 2:00 AM with dull, boring epigastric pain" is the classic presentation of a peptic ulcer due to the early morning peak in gastric acid secretion.
• Duodenal vs. Gastric Ulcers: Board questions frequently test the distinction based on eating. Duodenal ulcer pain is classically relieved by food intake, whereas gastric ulcer pain is exacerbated by eating.
• Most Common Sites: If asked for the most common cause of upper GI bleeding, the answer is Peptic Ulcer Disease. If asked which ulcer most commonly perforates, the answer is the duodenal ulcer (accounting for 60% of all perforations), followed by antral gastric ulcers (20%).
• Diagnostic Distractor: If a patient presents with hematemesis, an option might suggest a lower GI bleed. Look for a BUN:Creatinine ratio > 30; this is highly predictive of an upper GI bleed.

8. THE BOARDROOM SCRIPT (OSCE & Oral Board Tips)

• The Initial Hook: "The patient presents with severe epigastric pain. Because this shares an afferent neural pathway with the heart, my immediate critical action is to order a 12-lead ECG and Troponin to rule out an Acute Myocardial Infarction. I am also ordering a CBC, Lipase, and a BUN-to-Creatinine ratio."
• The Physical Exam: "I will examine the abdomen for rigidity or rebound tenderness suggesting peritonitis, and I must perform a rectal examination to assess for melena or occult blood."
• The Imaging Decision: "The patient has peritoneal signs. I am ordering an immediate upright chest X-ray to look for free air under the diaphragm. However, if it is negative, I will not stop there; I will proceed to a CT scan of the abdomen with contrast to definitively rule out a perforation."
• The Disposition: "The patient's ECG is normal, labs are reassuring without anemia, and there are no alarm features such as weight loss or melena. I will discharge the patient with a prescription for a daily Proton Pump Inhibitor, arrange outpatient H. pylori testing and GI follow-up, and provide strict return precautions for hematemesis, melena, or intractable pain."