The administration of sodium polystyrene sulfonate (SPS) is used extensively for the treatment of hyperkalemia, especially in patients with renal failure [1
]. Other uses have been reported, however [4
]. SPS is an ion-exchange resin that exchanges Na+
in the gastrointestinal tract, especially in the colon, and increases the fecal excretion of potassium ions. It can be administered orally or rectally suspended in sorbitol, water, or dextrose. Historically, reports of ischemic colitis and colonic necrosis after rectal administration of SPS in sorbitol solution are abundant in the literature, but rare for the upper gastrointestinal tract [8
]. Other complications such as thrombocytopenia [19
] and rectal stenosis [20
] have been reported. Administration of SPS suspended in dextrose or water has been suggested to avoid sorbitol related complications; however, recent reports have shown sorbitol-free SPS enemas to cause similar colonic catastrophes [21
SPS aspiration is a potential complication of oral administration, especially in debilitated patients [22
]. One study reports an incidence of intestinal necrosis in 1.8% of post operative patients [13
]. The aspiration of SPS was first described by Oi [24
] in 1978 in a post term hyperkalemic female infant with meconium aspiration. After a second oral administration the infant became cyanotic, bradycardic, apneic, and expired [24
]. The microscopic appearance of the intraalveolar material was then compared to a solution of 25% SPS which yielded similar histological features [24
]. In an animal model, Haupt et al [25
] demonstrated that the inflammatory reaction following SPS aspiration is not solely attributed to concomitant aspiration of gastric contents.
The purpose of this report is to document a rare, often undiagnosed, and fulminant cause of death among patients with renal failure under the administration of potassium lowering agents. The particular appearance of SPS on histological sections should highlight it as a possible cause of aspiration pneumonia. In our patient, SPS aspiration superimposed on an already compromised pulmonary function was the immediate cause of death. Both methods of administration of the cation exchange resin have been proven effective, but rectal administration may prove beneficial in avoiding aspiration pneumonitis in chronically ill and debilitated patients.