2020 Volume 53 Issue 12 Pages 985-991
The patient was a 63-year-old male who had been on hemodialysis for 19 years because of end-stage renal failure due to diabetic nephropathy and who had been taking oral calcium polystyrene sulfonate (CPS) as a treatment for hyperkalemia. Previously, he underwent detailed tests for progressive anemia and black stools, and was diagnosed with descending colon cancer, for which he was treated by laparoscopic segmental colectomy of the descending colon with D3 lymphadenectomy. The postoperative course was uneventful and the patient was discharged on hospital day 11. However, because subsequent findings revealed progressive anemia and recurrence of bloody stools, lower gastrointestinal endoscopy was performed on hospital day 43. A bleeding circumferential ulcer was found at the anastomotic site and a longitudinal ulcer was detected at a different site. Biopsy of the ulcers revealed basophilic rhomboid deposits on the ulcer floor; thus, involvement of CPS was suspected. Hence, oral administration of CPS was discontinued, and as a result, anemia ceased to progress and subsequent lower gastrointestinal endoscopy showed improvement of the ulcers. Three years have passed and the patient has survived without recurrence of cancer or ulcers.
