Surgical case reports
Small Bowel-Vesical Fistula with Chronic Kidney Disease Relating to Administration of Sodium Polystyrene Sulfonate: A Case Report
By Kawahara H, Matsumoto T, Orimoto H and 4 others.
Abstract
Introduction
Sodium polystyrene sulfonate (SPS) is a cation-exchange resin indicated for the treatment of hyperkalemia in patients with chronic kidney disease (CKD); however, it is associated with severe gastrointestinal complications such as intestinal perforation, ulceration, and necrosis. Although SPS-related gastrointestinal injury has been well documented, small bowel-vesical fistula has not previously been reported. Here, we present a case of small bowel-vesical fistula associated with SPS therapy.
Case presentation
A 69-year-old man with CKD who was receiving SPS therapy presented to a local clinic with the passage of food particles in his urine. The patient was subsequently referred to our institution for further evaluation and management. CT revealed a fistula between the small intestine and the urinary bladder, prompting surgical intervention. Partial resection of the small bowel and partial cystectomy were performed to excise the fistulous tract. Postoperatively, the patient developed an anastomotic leak in the small bowel that required ileostomy. His condition subsequently improved, and he was discharged from the hospital. Histopathological examination of the tissue surrounding the fistula demonstrated an inflammatory infiltrate predominantly composed of plasma cells, along with numerous basophilic polygonal crystals consistent with SPS. These pathological findings supported an association between SPS deposition and intestinal injury as a possible underlying mechanism of small bowel-vesical fistula formation. To our knowledge, this is the first reported case of small bowel-vesical fistula associated with SPS therapy.