Erosive Gastritis

Gastritis with multiple superficial mucosal breaks (erosions, not extending beyond the muscularis mucosae), with or without haemorrhage.

• Causes: NSAIDs and aspirin, alcohol, critical illness and physiological stress, H. pylori, bile reflux, Crohn disease, cytomegalovirus and herpes simplex infection, radiation, cocaine, chemotherapy, ingestion of iron or potassium tablets, and caustic agents.
• Accounts for up to about 10 to 15% of upper gastrointestinal bleeding; most erosions are asymptomatic, and 20 to 30% of regular NSAID users have erosions.
• Mechanism: loss of mucosal defence (prostaglandin depletion, ischaemia, direct injury) with back diffusion of acid and surface epithelial necrosis, which heals within days if the cause is removed.

Epigastric pain, nausea, vomiting, loss of appetite; many have no symptoms until bleeding occurs.

• Haematemesis (fresh blood or coffee grounds), melaena, iron deficiency anaemia, dizziness or syncope with larger blood loss.
• Examination: epigastric tenderness, pallor, tachycardia and hypotension in haemorrhage.
• Differential diagnosis: peptic ulcer, Mallory-Weiss tear, oesophagitis, varices and portal hypertensive gastropathy, Dieulafoy lesion, angiodysplasia, gastric cancer, gastric antral vascular ectasia.
• Complications: acute gastrointestinal bleeding with shock, iron deficiency anaemia, progression to ulcer, rarely perforation, and rebleeding.

Endoscopy (within 24 hours for bleeding, after resuscitation): multiple small haemorrhagic or flat erosions, often in the antrum, with or without surface blood; biopsy for histology and H. pylori; exclude ulcer, varices and tumour.

• Blood tests: full blood count, urea (raised in bleeding), creatinine, electrolytes, liver tests, clotting profile, group and crossmatch, lactate in shock.
• H. pylori testing by histology or rapid urease test at endoscopy, or urea breath test or stool antigen after stopping proton pump inhibitors for 2 weeks (a false negative is common during bleeding, so repeat later).
• Risk scoring for bleeding (a validated score at presentation) helps decide on admission versus outpatient care.

Remove the cause: stop NSAIDs, alcohol and irritant drugs (continue aspirin 75 mg daily for secondary cardiovascular prevention once bleeding is controlled, within 1 to 7 days, with a proton pump inhibitor).

• Acid suppression:
  • Omeprazole 40 mg daily (or pantoprazole 40 mg daily, esomeprazole 40 mg daily) for 4 to 8 weeks.
  • Bleeding: omeprazole 80 mg IV bolus then 8 mg/hour for 72 hours (or 40 mg IV twice daily), then oral omeprazole 40 mg twice daily for 2 weeks, then 40 mg daily.
• Resuscitation of bleeding: two large-bore cannulae, crystalloid, transfuse red cells at a haemoglobin of 70 g/L (80 g/L in cardiovascular disease), correct coagulopathy (platelets to 50 x 10^9/L or more, vitamin K 10 mg IV and prothrombin complex concentrate 25 to 50 units/kg for warfarin related bleeding with INR more than 1.5), hold anticoagulants, and monitor in a high-dependency setting.
• Endoscopic therapy for active bleeding or a visible vessel: adrenaline 1 in 10,000 injection (up to 10 mL) combined with a thermal probe or haemoclip; diffuse erosive oozing often stops with acid suppression and local adrenaline.
• Refractory bleeding: repeat endoscopy, selective angiographic embolisation, or surgery (rare).
• Mucosal protectants (evidence limited): sucralfate 1 g four times daily on an empty stomach for 4 weeks (separate from other drugs by 2 hours; avoid in renal failure); misoprostol 200 micrograms four times daily with food to prevent NSAID injury (avoid in pregnancy; diarrhoea is common).
• Helicobacter pylori eradication when positive, for 14 days: omeprazole 20 mg twice daily with amoxicillin 1 g twice daily and clarithromycin 500 mg twice daily; or omeprazole 20 mg twice daily, bismuth subsalicylate 524 mg four times daily, tetracycline 500 mg four times daily and metronidazole 500 mg three to four times daily.
• Prevention in high-risk patients on NSAIDs: continue omeprazole 20 mg daily, or use celecoxib 100 to 200 mg twice daily with omeprazole 20 mg daily.
• Special groups: children (omeprazole 1 mg/kg once daily, maximum 20 to 40 mg; avoid NSAIDs and aspirin); pregnancy (alginates, famotidine 20 mg twice daily, omeprazole 20 mg daily, avoid misoprostol); elderly (stop NSAIDs, lower threshold for admission); renal impairment (famotidine 10 mg twice daily when creatinine clearance is below 50 mL/min, avoid aluminium compounds); critical illness (pantoprazole 40 mg IV daily); cirrhosis (check for varices and portal hypertensive gastropathy).
• Red flags: haematemesis, melaena, shock, haemoglobin falling by 20 g/L or more, ongoing bleeding after endoscopy, anticoagulant use, liver disease.
• Follow-up: review at 2 to 4 weeks; repeat haemoglobin and ferritin at 4 to 8 weeks; test of cure for H. pylori at 4 to 8 weeks; repeat endoscopy only when erosions are unexplained, a gastric ulcer is present, or bleeding recurs.