Peptic ulcer disease

Overview

Breach in mucosal lining of stomach or proximal duodenum penetrating through the muscularis mucosae. H. pylori and NSAIDs account for >90% of cases.

Aetiology

•H. pylori - gram-negative bacterium; produces urease → ammonia → mucosal disruption → ulceration. Associated with ~90% of duodenal ulcers and 70-80% of gastric ulcers (non-NSAID)

•NSAIDs - inhibit COX-1 → reduced prostaglandins → reduced mucus/bicarbonate → mucosal vulnerability. Risk systemic regardless of route

•Zollinger-Ellison syndrome - gastrinoma → massive acid hypersecretion → multiple/refractory/atypically located ulcers

•Other risk factors - smoking, alcohol, corticosteroids, aspirin, anticoagulants (including DOACs), SSRIs (increase bleeding risk from pre-existing ulcer)

Presentation

Gastric vs duodenal ulcer pain pattern

Feature	Gastric ulcer	Duodenal ulcer
Pain timing	Worse shortly after eating	Worse when empty (2-3 am), relieved by eating
Malignant risk	Yes - biopsy required	Negligible
PPI duration post-eradication	8 weeks	4-8 weeks
Repeat OGD required	Yes - at 6-8 weeks to confirm healing and exclude malignancy	Not routinely required

•Epigastric pain - burning, gnawing, or aching

•Haematemesis - bright red blood or coffee-ground vomiting

•Melaena - black, tarry, offensive stools from digested blood

•Iron deficiency anaemia - low Hb, low MCV, low ferritin from chronic occult blood loss

🚨

ALARM symptoms - refer urgently (2-week-wait OGD): Anaemia (iron deficiency), Loss of weight, Anorexia, Recent/progressive symptoms, Melaena or haematemesis, Swallowing difficulty (dysphagia). Also: age ≥55 with new dyspepsia + weight loss and/or upper abdominal pain.

Investigations

•First-line (non-invasive H. pylori testing):

•Carbon-13 urea breath test - detects active infection; labelled urea broken down by urease → labelled CO2 in expired breath

•Stool antigen test (HpSA) - validated alternative for initial diagnosis and eradication confirmation

•Serum H. pylori antibody - cannot distinguish active from past infection; cannot confirm eradication - limited clinical use

•FBC and iron studies - screen for iron deficiency anaemia

🏆 Gold standard

•OGD - direct visualisation, biopsy (essential for gastric ulcers to exclude malignancy), rapid urease test (CLO test) at same time. Indicated for all ALARM symptoms and age ≥55 with new dyspepsia

⚠️

Stop PPI at least 4 weeks and antibiotics at least 2 weeks before urea breath test or stool antigen test - otherwise false negative results for H. pylori.

Management

•First-line - stop NSAIDs where clinically possible; if NSAIDs cannot be stopped, co-prescribe a PPI for gastroprotection

•First-line - H. pylori eradication (7-day triple therapy): lansoprazole or omeprazole (PPI) twice daily + clarithromycin 500 mg twice daily + amoxicillin 1 g twice daily (or metronidazole 400 mg twice daily if penicillin-allergic). Achieves eradication in ~70-85%

•Continue PPI for 4-8 weeks (duodenal) or 8 weeks (gastric) after eradication to ensure mucosal healing

•Lifestyle - smoking cessation, reduce alcohol, avoid caffeine and precipitating foods

•Second-line (failed triple therapy): repeat eradication with different antibiotics; quadruple therapy - PPI + bismuth + metronidazole + tetracycline

•Third-line (refractory/complications): surgery - Billroth I (pyloric/duodenal), Billroth II (fundal/large gastric), or vagotomy

⚠️

Metronidazole and alcohol - disulfiram-like reaction (flushing, nausea, palpitations). Patients must avoid alcohol during the course and for 48 hours after the last dose.

Follow-up

•Confirm eradication using urea breath test or stool antigen test - at least 4 weeks after completing therapy and 2 weeks after stopping PPI. Serum antibody tests cannot confirm eradication

•Repeat OGD at 6-8 weeks for all gastric ulcers - confirm healing and take further biopsies to exclude malignancy. Not required routinely for duodenal ulcers

•Persistent/recurrent symptoms after successful eradication - investigate for Zollinger-Ellison syndrome (fasting serum gastrin)

Complications

•Perforation - full-thickness erosion → peritonitis; sudden severe generalised abdominal pain, board-like rigidity. Erect CXR shows free air under diaphragm (pneumoperitoneum) in ~70-80%. Surgical emergency

•Upper GI haemorrhage - haematemesis, melaena, haemodynamic instability; urgent resuscitation + emergency OGD for haemostasis (adrenaline injection, thermal coagulation, haemoclip). Risk stratified by Rockall score

•Gastric outlet obstruction - pyloric scarring → projectile vomiting of undigested food, succussion splash, hypochloraemic hypokalaemic metabolic alkalosis

•Malignant transformation - gastric ulcers only (not duodenal); underlies need for biopsy and repeat OGD

•Iron deficiency anaemia - from chronic occult bleeding; may be presenting feature