From Kelly Townsend at Tricore Labs: We have a patient whose platelets clump in every anticoagulant we’ve tried. He has normal prothrombin time, partial thromboplastin time, fibrinogen, and von Willebrand disease panel results, but oozes after even minor procedures. The clinicians want to evaluate platelet function, but we are hesitant because of his platelet clumping. Any suggestions for obtaining accurate platelet function analyzer (PFA-100) and/or platelet aggregation results in a platelet clumper? We use theChrono-log Lumiaggregometer (whole blood).
Hi, Kelly. This appears to be a pathological situation and not simple platelet satellitosis, and I doubt that while platelets are clumping that you will be able to generate a reliable aggregation response. You don’t list the anticoagulants that you’ve tried, but I assume they include the acid-citrate-dextrose (ACD) and the citrate-theophylline-adenosine-dipyridamole (CTAD) tube. Platelets may function in the former, however aggregometry is not validated on the ACD tube. The CTAD tube shuts down platelet function altogether and may work for generating an accurate platelet count, but not aggregometry. I once heard a talk from platelet expert James George MD in which he asserted that in unexplained thrombocytopenia, l