A Case of Aspiration of High-molecular Polymer Sevelamer Hydrochloride That Caused Dyspnea

Abstract

Background. The phosphate binder sevelamer hydrochloride is a high-molecular-weight polymer. It becomes gelatinous and expands eight-fold in aqueous solutions. Sevelamer crystals deposited on the mucosa can lead to mucosal injury. Case. A 67-year-old man with chronic renal disease had received maintenance hemodialysis for about 4 years. In early June of X, he choked on a tablet of sevelamer hydrochloride (Phosblock^®) before breakfast. He felt continuous discomfort in his pharynx and mild dyspnea. His respiratory symptoms worsened during hemodialysis that afternoon. Chest computed tomography showed stenosis of the left basal bronchus and atelectasis of the left S⁸. Bronchoscopy showed edematous mucosa from the left lower lobe bronchus to the basal bronchus and gel-like white foreign bodies adhering to the basal bronchus, thought to be bronchial foreign bodies of sevelamer hydrochloride. We removed the bodies as much as possible using biopsy forceps and a brush. Conclusion. Sevelamer hydrochloride has a property of expanding on water absorption. Therefore, sevelamer aspiration is likely to cause airway obstruction. It is also necessary to be aware of the risk of mucosal injury due to sevelamer crystals.