Development of Colonic Perforation during Calcium Polystyrene Sulfonate Administration: A Case Report.

A 90-year-old female complaining of severe upper abdominal pain was transferred to our institution. The patient had been prescribed with calcium polystyrene sulfonate (CPS) for the treatment of hyperkalemia following myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) associated glomerulonephritis. Physical examination revealed diffuse tenderness over the abdomen, with signs of peritoneal irritation.