To Kayexalate or Not to Kayexalate

ABSTRACT

Introduction: Although rare, it is important to consider colon necrosis, ulceration, and perforation in the management of patients with abdominal pain following kayexalate administration. We present a critically ill patient requiring partial hemicolectomy following kayexalate for hyperkalemia. Case Description A 43-year-old male presented to the ER via EMS after being intubated emergently in the field. Was found to be COVID-19 positive and admitted to the ICU. Creatinine and potassium started trending up after day 5, requiring multiple doses of calcium gluconate, insulin, and dextrose, along with 4 doses of kayexalate 30 g over the second week. On the 10th day, he started spiking fever, having abdominal distension, and continued desaturating. Abdominal x-ray showed a large amount of free intraperitoneal air warranting emergent ex lap with partial right hemicolectomy and end ileostomy. Unfortunately, he was pronounced dead after a lengthy hospital stay of 55 days. The specimen showed perforation, mucosal necrosis, and acute serositis. It also showed Amphophilic crystals suggesting a diagnosis of kayexalate-induced colon ischemia and necrosis. Discussion(s) Kayexalate was approved by the FDA in 1958 and has been used to treat hyperkalemia. It can bind intraluminal calcium, leading to bowel obstruction or perforation, with a reported incidence of 0.14-1.8%. The identification of rhomboid or triangular, basophilic crystals with a mosaic pattern on H&E stain is pathognomonic for the presence of kayexalate. We present this case as a reminder of the rare yet devastating complications of kayexalate. For that reason, clinical suspicion should be raised in patients with abdominal pain following kayexalate. Kayexalate should only be used in patients who have life-threatening hyperkalemia where dialysis or newer cation exchangers (ie, patiromer or Lokelma) are not available, and other therapies to remove potassium have failed or are not possible. (Figure Presented).