Hematochezia in a Patient with Renal Failure and Hyperkalemia

68-year-old man with history of hypertension, type 2 diaetes mellitus, coronary artery disease, aortic stenosis and hronic kidney disease. Relevant medications included bisorolol, furosemide, atorvastatin, perindopril/amlodipine, etformin/sitagliptin and aspirin. The patient was admited in the emergency department for acute decompensated eart failure and acute-on-chronic renal failure with hyperalemia. He began treatment with cation exchange resin 40 g/day), which was continued for 3 days. On the fourth ay of hospitalization, the patient presented hematochezia ith hemodynamic repercussion and anemia (hemoglobin, .5 g/dl). Two units of packed red blood cells have been ransfused and an endoscopic examination was requested, he colonoscopy revealed three ulcers with about 10 mm, ongested and edematous surrounding mucosa, in the proxmal ascending colon (Fig. 1). Histological evaluation of the lcer biopsies identified several rhomboid crystals of sodium olystyrene sulfonate. This clinical case was assumed to be a odium polystyrene sulfonate-induced colitis (Figs. 2 and 3). he patient was discharged without evidence of rebleeding.