Sodium polystyrene sulfonate crystals in the gastric wall of a patient with upper gastrointestinal bleeding and gastric perforation: an incidental finding or a pathogenic factor?

Sodium polystyrene sulfonate, or Kayexalate, is an ion-exchange resin used to treat hyperkalemia. It is sometimes used with sorbitol, an osmotic laxative that prevents constipation. Small and large bowel necrosis and perforation due to Kayexalate were previously reported. However, no previous cases of gastric perforation were described. We present a case of gastric perforation in a 48-year-old patient, with chronic kidney disease (CKD), lung transplant under chronic corticosteroids, and two previous Nissen fundoplications. He presented with sudden epigastralgia, hematemesis and hemodynamic instability. Esophagogastroduodenoscopy was not able to localize the site of bleeding. Surgical exploration revealed perforation of the lesser curvature of the stomach. Antrectomy with a Billroth II reconstruction was performed. Pathological examination revealed no abnormalities except fibrinoleukocytic debris with Kayexalate crystals in the gastric wall. Kayexalate is believed to be a trigger for the gastric injury in a patient with tissues impaired by corticosteroids, CKD and immunosuppressors.