Gastric Disorders

Peptic Ulcer Disease - Ulcer Woes & Fixes

• Etiology: H. pylori (commonest), NSAIDs, smoking, ZES. Stress ulcers (Cushing's - CNS; Curling's - burns).
• Types & Pain:
  • DU: Pain ↓ post-meal, nocturnal. More common.
  • GU: Pain ↑ post-meal. Malignancy risk (biopsy vital).
• Diagnosis: Endoscopy + biopsy (CLO, histology). Urea Breath Test (H. pylori).
• Complications:
  • Bleeding (most common): Hematemesis/melena. Forrest class. Endoscopic hemostasis.
  • Perforation (anterior DU): Acute abdomen. X-ray: gas under diaphragm.

    ⭐ Most common site of peptic ulcer perforation is the anterior aspect of the first part of the duodenum.

  • Gastric Outlet Obstruction (GOO): Vomiting, succussion splash.
  • Penetration (e.g., pancreas).
• Management:
  • Medical: PPIs, H. pylori eradication (📌 OAM/BMT triple therapy, 7-14 days).
  • Surgical: For complications (Graham omentopexy for perforation), intractability. Vagotomy (HSV for DU), antrectomy, drainage.

Gastric Outlet Obstruction - Blocked Exit Strategies

• Etiology: Peptic Ulcer Disease (PUD) (cicatrization), malignancy (antral Ca), gastric polyps, Bouveret's syndrome. 📌 Infants: Hypertrophic Pyloric Stenosis.
• Features: Non-bilious projectile vomiting, early satiety, epigastric pain/fullness, weight loss, dehydration, succussion splash.
• Diagnosis:
  • Upper GI Endoscopy + Biopsy: Gold standard.
  • Barium meal: Dilated stomach, delayed emptying.
  • Saline load test: >400mL residual after 30 min indicates obstruction.
• Management:
  • Initial: NGT decompression, IV fluids (correct electrolytes), PPIs.
  • Definitive: Endoscopic balloon dilation (benign), EUS-guided gastrojejunostomy, surgical (Gastrojejunostomy, Antrectomy).

⭐ Classic electrolyte imbalance: Hypochloremic, hypokalemic metabolic alkalosis with paradoxical aciduria due to vomiting HCl.

Gastric Carcinoma - Cancer's Gastric Grip

• Risk Factors: H. pylori (key), diet (↑salt, nitrates, smoked foods), smoking, chronic atrophic gastritis, pernicious anemia, Blood Group A, CDH1 mutation.

• Lauren Classification:

  • Intestinal: Glandular, older males, H.pylori-assoc., better prognosis.
  • Diffuse: Signet ring cells, younger, linitis plastica, poorer prognosis.

• Clinical: Late symptoms: weight loss, abd. pain, dysphagia, early satiety.

  • Metastatic signs: Virchow's node, Sister Mary Joseph's nodule, Krukenberg tumor.

• Diagnosis: EGD + multiple biopsies.

• Staging: TNM; CECT, EUS for depth/nodes.

• Treatment: Surgery (gastrectomy + D2 lymphadenectomy) for resectable. Perioperative chemotherapy.

  

  ⭐ Most common site of gastric cancer is the antrum; however, proximal gastric cancers are increasing in incidence in Western countries.

Miscellaneous Gastric Issues - Gastric Grab Bag

• Gastrointestinal Stromal Tumor (GIST):
  • Most common mesenchymal GI tumor; from Interstitial cells of Cajal.
  • Key mutation: c-KIT (CD117) - diagnostic marker.
  • Treatment: Imatinib.
  • 
• Zollinger-Ellison Syndrome (ZES):
  • Gastrinoma → ↑Gastrin → ↑Acid → Multiple, distal peptic ulcers.
  • Diagnosis: Fasting serum gastrin >1000 pg/mL & gastric pH <2.
  • Often associated with MEN-1.
• Gastritis Types:
  • Type A (Autoimmune): Fundus/Body; Pernicious Anemia; Achlorhydria.
  • Type B (Bacterial): H. pylori infection; Antrum; Most common.
  • Type C (Chemical): NSAIDs, bile reflux.

⭐ Carney's Triad (for extra-adrenal paraganglioma, GIST, pulmonary chondroma) is a rare, non-hereditary syndrome predominantly affecting young females. (Note: ZES is gastrinoma, not part of Carney's Triad directly, but GIST is.)

• Ménétrier's Disease:
  • Giant hypertrophic gastropathy; ↑mucus, ↓acid; protein-losing enteropathy.
• Dieulafoy's Lesion:
  • Aberrant submucosal artery; causes massive GI bleed; often lesser curvature.

High‑Yield Points - ⚡ Biggest Takeaways

• H. pylori: main cause of PUD & gastric MALT lymphoma.
• Zollinger-Ellison syndrome: multiple refractory ulcers, ↑ serum gastrin.
• Gastric adenocarcinoma: linked to H. pylori, nitrosamines; signet ring cells imply poor prognosis.
• GISTs: most common mesenchymal gastric tumors, CD117+, treat with imatinib.
• Dumping syndrome (post-gastrectomy): early (osmotic diarrhea), late (reactive hypoglycemia).
• Type A gastritis (autoimmune): body/fundus, pernicious anemia; Type B (H. pylori): antrum.