title: Whole blood platelet aggregation and release reaction testing in uremic patients.
abstract: BACKGROUND
  Platelet function analysis utilizing platelet-rich plasma and optical density based aggregometry fails to identify patients at risk for uremia associated complications.
  
  
  METHODS
  We employed whole blood platelet aggregation analysis based on impedance as well as determination of ATP release from platelet granules detected by a chemiluminescence method. Ten chronic kidney disease (CKD) stage 4 or 5 predialysis patients underwent platelet evaluation. Our study aims to evaluate this platform in this patient population to determine if abnormalities could be detected.
  
  
  RESULTS
  Analysis revealed normal aggregation and ATP release to collagen, ADP, and high-dose ristocetin. ATP release had a low response to arachidonic acid (0.37 ± 0.26 nmoles, reference range: 0.6-1.4 nmoles). Platelet aggregation to low-dose ristocetin revealed an exaggerated response (20.9 ± 18.7 ohms, reference range: 0-5 ohms).
  
  
  CONCLUSIONS
  Whole blood platelet analysis detected platelet dysfunction which may be associated with bleeding and thrombotic risks in uremia. Diminished ATP release to arachidonic acid (an aspirin-like defect) in uremic patients may result in platelet associated bleeding. An increased aggregation response to low-dose ristocetin (a type IIb von Willebrand disease-like defect) is associated with thrombus formation. This platelet hyperreactivity may be associated with a thrombotic diathesis as seen in some uremic patients.
authors.affiliation: Department of Pathology, George Washington University Medical Center, 900 23rd Street NW, Washington, DC 20037, USA.
authors.forename: Jay
authors.initials: J
authors.lastname: Zeck
authors.forename: Jason
authors.initials: J
authors.lastname: Schallheim
authors.forename: Susie Q
authors.initials: SQ
authors.lastname: Lew
authors.forename: Louis
authors.initials: L
authors.lastname: DePalma
mesh_terms: D000328:Adult; D000368:Aged; D058266:Dielectric Spectroscopy / Q000379:methods*; D005260:Female; D006801:Humans; D008163:Luminescent Measurements / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation; D010979:Platelet Function Tests / Q000379:methods*; D051436:Renal Insufficiency, Chronic / Q000097:blood* / Q000150:complications / Q000175:diagnosis*; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D014511:Uremia / Q000097:blood* / Q000175:diagnosis* / Q000209:etiology