Nonneoplastic disorders
Kayexalate damage

Author: Elliot Weisenberg, M.D. (see Authors page)

Revised: 26 July 2018, last major update December 2012

Copyright: (c) 2003-2018,, Inc.

PubMed Search: Kayexalate damage

Cite this page: Weisenberg, E. Kayexalate damage. website. Accessed October 16th, 2018.
Definition / general
  • Kayexalate (sodium polystyrene sulfonate) in sorbitol is used to treat hyperkalemia
  • Symptoms are from sorbitol, given orally though NG tube or as an enema, may crystallize in esophagus, stomach or duodenum and produce endoscopic ulcers and erosions resembling carcinoma or Candida (Am J Surg Pathol 2001;25:637)
  • Colonic infarction and erosions reported
Case reports
Microscopic (histologic) description
  • Crystals are lightly basophilic with a faint crystalline mosaic pattern, better seen with PAS / Alcian blue
  • Crystals are refractile but not polarizable, luminal and adherent to intact surface epithelium or mixed with inflammatory exudate in patients with ulcer or erosion
Microscopic (histologic) images

Images hosted on PathOut server:

Contributed by Dr. Ankur Sangoi

AFB stain

Board review question #1
Which of the following microscopically identifiable medication materials typically shows a two tone appearance with a fish scale pattern on H&E?

A. Cholestyramine
B. Crospovidone
C. Sevelamer
D. Sodium polystyrene sulfonate

Board review answer #1
C. Sevelamer