Gastritis and peptic ulcer disease

Gastritis - Stomach's Fiery Fury

Inflammation of the stomach lining. Acute involves neutrophilic infiltrate, while chronic gastritis shows lymphocytes and plasma cells, often with intestinal metaplasia.

⭐ H. pylori is the most common cause of chronic gastritis and is strongly associated with the development of peptic ulcer disease, gastric adenocarcinoma, and MALT lymphoma.

H. pylori - The Spiral Bandit

• Gram-negative, spiral-shaped bacterium primarily colonizing the gastric antrum.
• Virulence Factors:
  • Urease: Neutralizes gastric acid by converting urea to ammonia, allowing survival.
  • CagA, VacA: Cytotoxins that promote inflammation and ulceration.
• Clinical Associations:
  • Chronic gastritis & peptic ulcer disease (>90% of duodenal ulcers).
  • Gastric adenocarcinoma & MALT lymphoma.

⭐ Eradication of H. pylori can lead to complete regression of MALT lymphoma.

Peptic Ulcer Disease - Digging Deep

• Etiology: Imbalance between mucosal defenses & acidic environment.
  • Primary Culprits: H. pylori infection (>90% of duodenal, >70% of gastric), NSAIDs (↓ prostaglandins).
  • Less Common: Zollinger-Ellison syndrome, smoking, stress (Cushing/Curling ulcers).
• Clinical Features:
  • Duodenal Ulcer: Epigastric pain improves with meals. More common.
  • Gastric Ulcer: Epigastric pain worsens with meals.
  • 📌 Mnemonic: DUde, food helps DUodenal.
• Complications: Hemorrhage, perforation, gastric outlet obstruction.

⭐ Perforated Ulcer: Presents as sudden, severe abdominal pain, often with free air under the diaphragm on X-ray and referred pain to the shoulder (Kehr's sign) due to phrenic nerve irritation.

Zollinger-Ellison - Gastrin Gone Wild

• Gastrinoma: A gastrin-secreting neuroendocrine tumor, typically in the duodenum or pancreas.
• Pathophysiology: ↑ Gastrin → parietal cell hyperplasia → massive ↑ acid secretion.
• Presentation: Multiple, treatment-refractory ulcers (including distal duodenum/jejunum), abdominal pain, and chronic diarrhea (steatorrhea).
• Diagnosis: ↑ Fasting serum gastrin (>1000 pg/mL) with gastric pH < 4; positive secretin stimulation test.

⭐ Roughly 25% of gastrinomas are associated with Multiple Endocrine Neoplasia Type 1 (MEN1).

PUD Complications - Alarming Perforations

• Most common site: Anterior duodenum > anterior stomach.
• Presentation: Sudden onset of severe, diffuse abdominal pain.
  • Classic finding: Rigid, board-like abdomen.
• Diagnosis: Upright chest X-ray shows pneumoperitoneum (free air under the diaphragm).
• Sequelae: Leads to chemical peritonitis from gastric contents.

⭐ Kehr's Sign: Subdiaphragmatic free air can irritate the phrenic nerve, causing referred pain to the shoulder.

High‑Yield Points - ⚡ Biggest Takeaways

• *H. pylori is the leading cause of gastritis, peptic ulcers, and gastric adenocarcinoma.
• Autoimmune gastritis involves T-cell mediated destruction of parietal cells, leading to pernicious anemia.
• NSAIDs cause ulcers by inhibiting prostaglandin synthesis, reducing mucosal protection.
• Duodenal ulcer pain improves with meals, while gastric ulcer pain worsens.
• Suspect Zollinger-Ellison syndrome with multiple, distal, or refractory ulcers.
• Upper GI bleeding is the most common complication; perforation is the most lethal.