Emphysematous Gastritis Precipitated by Malignant Gastric Outlet Obstruction from Advanced Pancreatic Ductal Adenocarcinoma.

Introduction: Emphysematous gastritis is a rare, frequently fatal infection of the gastric wall caused by gas-forming organisms. Gastric outlet obstruction is well recognised as a cause of benign gastric emphysema but is seldom reported as a precipitant of emphysematous gastritis. This report adds a rare presentation of emphysematous gastritis with malignant gastric outlet obstruction as a risk factor. Case description: An 86-year-old man with locally advanced pancreatic ductal adenocarcinoma presented after a fall preceded by generalised weakness, abdominal bloating, diarrhoea, nausea and fever. He was hypotensive and tachycardic, with acute kidney injury and severe high anion gap metabolic acidosis. Computed tomography scan demonstrated a markedly distended stomach with intramural gas and distal obstruction from progressive pancreatic malignancy; blood cultures were negative. He was managed non-operatively with aggressive resuscitation, broad-spectrum intravenous antibiotics and gastric decompression, with subsequent clinical, biochemical and radiological improvement. Conclusion: Malignant gastric outlet obstruction, compounded by chemotherapy-related immunosuppression, can precipitate emphysematous gastritis. In selected patients without perforation or ischaemia, even those who are frail and immunocompromised, conservative management can achieve resolution. LEARNING POINTS: Malignant gastric outlet obstruction from advanced pancreatic cancer can precipitate emphysematous gastritis, a rare and often fatal infection, particularly when compounded by chemotherapy-related immunosuppression.This case adds to the growing evidence that carefully selected patients without perforation or ischaemia can be managed conservatively with antibiotics and gastric decompression rather than surgery.