Characterised by chronic inflammation of the gastric mucosa with atrophy, gland loss and metaplastic changes

Aetiology

• Autoimmune

Pathophysiology

Autoimmune destruction of parietal cells

• Decreased HCl production → increased gastrin → G cell hyperplasia → hypergastrinemia
• Hypergastrinemia can lead to hyperplasia of enterochromaffin-like cells → carcinoid tumours

Production of autoantibodies against intrinsic factor

• Results in B12 deficiency - ‘macrocytic’ anaemia
• B12 is required for DNA synthesis

Clinical features

• Haematemesis, melaena
• Epigastric pain
• Nausea and vomiting
• Dyspepsia
• Symptoms of anaemia/B12 deficiency

Investigations

• Bloods: ↓ B12
• Endoscopy + biopsy: typically looks very atrophic due to persistent and progressive damage to the parietal cells

Management