I was intrigued by the comments related to dextran sulfate added by Gary Bullard andHerb Crown to the falsely elevated anti-Xa discussion that started with a question from an unknown participant on January 17, 2011. Though both Gary and Herb indicated that dextran releases heparin from endothelial cells, I wondered if dextran’s polysaccharide structure could directly interact in the anti-Xa reaction, substituting for heparin. This drove me to PubMed, where I could find no reference linking dextran to heparin or to an elevated chromogenic anti-Xa heparin assay. Likewise, the specialty techs at UAB could not confirm this in their experience. I may be missing something important, so I’m asking Gary, Herb, or anyone else with experience to point us to a publication linking dextran to falsely elevated anti-Xa heparin results. Thanks. Geo.