title: Platelets of patients with chronic kidney disease demonstrate deficient platelet reactivity in vitro.
abstract: BACKGROUND
  In patients with chronic kidney disease studies focusing on platelet function and properties often are non-conclusive whereas only few studies use functional platelet tests. In this study we evaluated a recently developed functional flow cytometry based assay for the analysis of platelet function in chronic kidney disease.
  
  
  METHODS
  Platelet reactivity was measured using flow cytometric analysis. Platelets in whole blood were triggered with different concentrations of agonists (TRAP, ADP, CRP). Platelet activation was quantified with staining for P-selectin, measuring the mean fluorescence intensity. Area under the curve and the concentration of half-maximal response were determined.
  
  
  RESULTS
  We studied 23 patients with chronic kidney disease (9 patients with cardiorenal failure and 14 patients with end stage renal disease) and 19 healthy controls. Expression of P-selectin on the platelet surface measured as mean fluorescence intensity was significantly less in chronic kidney disease patients compared to controls after maximal stimulation with TRAP (9.7 (7.9-10.8) vs. 11.4 (9.2-12.2), P=0.032), ADP (1.6 (1.2-2.1) vs. 2.6 (1.9-3.5), P=0.002) and CRP (9.2 (8.5-10.8) vs. 11.5 (9.5-12.9), P=0.004). Also the area under the curve was significantly different. There was no significant difference in half-maximal response between both groups.
  
  
  CONCLUSIONS
  In this study we found that patients with chronic kidney disease show reduced platelet reactivity in response of ADP, TRAP and CRP compared to controls. These results contribute to our understanding of the aberrant platelet function observed in patients with chronic kidney disease and emphasize the significance of using functional whole blood platelet activation assays.
authors.affiliation: Department of Clinical Chemistry and Hematology, University Medical Center Utrecht, Heidelberglaan 100, 3584, CX, Utrecht, The Netherlands.
authors.forename: Esther R
authors.initials: ER
authors.lastname: van Bladel
authors.forename: Rosa L
authors.initials: RL
authors.lastname: de Jager
authors.forename: Daisy
authors.initials: D
authors.lastname: Walter
authors.forename: Loes
authors.initials: L
authors.lastname: Cornelissen
authors.forename: Carlo A
authors.initials: CA
authors.lastname: Gaillard
authors.forename: Leonie A
authors.initials: LA
authors.lastname: Boven
authors.forename: Mark
authors.initials: M
authors.lastname: Roest
authors.forename: Rob
authors.initials: R
authors.lastname: Fijnheer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001792:Blood Platelets / Q000276:immunology* / Q000473:pathology*; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015539:Platelet Activation / Q000276:immunology*; D006435:Renal Dialysis; D051436:Renal Insufficiency, Chronic / Q000276:immunology* / Q000473:pathology* / Q000534:rehabilitation; D016896:Treatment Outcome