title: A pilot study to assess the hemostatic function of pathogen-reduced platelets in patients with thrombocytopenia.
abstract: BACKGROUND
  Platelet (PLT) support is critical to the care of patients with thrombocytopenia, but allogeneic transfusions carry risk. Pathogen reduction mitigates some transfusion risks, but effects on PLT function remain a concern. This clinical pilot study assessed the effect of pathogen reduction technology with riboflavin plus ultraviolet light using thrombelastography (TEG).
  
  
  METHODS
  This prospective, randomized, crossover study compared Mirasol-treated (MIR) and standard reference (REF) PLT transfusions. PLT counts and TEG measurements were taken at pretransfusion and 1- and 24-hour-posttransfusion time points. The primary outcome measure was the pretransfusion to 1-hour-posttransfusion change in maximum amplitude (ΔMA(1 hr)). Secondary endpoints included ΔMA among other time points, relative MA, and the PLT count-MA correlation.
  
  
  RESULTS
  Of 16 enrolled patients, one withdrew before study treatment and three did not require two transfusions, leaving 12 patients in the efficacy analyses (seven MIR-REF, five REF-MIR). ΔMA(1 hr) (mean ± SD) was 10.60 ± 6.47 mm for MIR and 14.33 ± 5.38 mm for REF (p = 0.20, n = 10). ΔMA(24hr) was 9.49 ± 7.94 for MIR and 7.13 ± 3.08 for REF (p = 0.38, n = 9); ΔMA(24hr-1 hr) was -1.11 ± 2.95 for MIR and -7.20 ± 4.81 for REF (p = 0.016, n = 8). MA values for MIR and REF correlated with the log of PLT count (rMIR = 0.6901, rREF = 0.7399).
  
  
  CONCLUSIONS
  TEG is sensitive to changes in hemostatic function resulting from a single PLT transfusion. MIR and REF provided similar increments in hemostatic function in the immediate posttransfusion period and at 24 hours. A significant difference detected for ΔMA(24hr-1 hr) suggests different PLT clearance mechanisms. The relationship of these variables to clinically meaningful outcomes, for example, bleeding events or transfusion requirements, has yet to be determined.
authors.affiliation: Department of Clinical Immunology, Section of Transfusion Medicine, Copenhagen, Denmark; Department of Hematology, University of Copenhagen, Copenhagen, Denmark; Terumo BCT, Lakewood, Colorado.
authors.forename: Pär I
authors.initials: PI
authors.lastname: Johansson
authors.forename: Anne Catrine
authors.initials: AC
authors.lastname: Simonsen
authors.forename: Peter N
authors.initials: PN
authors.lastname: Brown
authors.forename: Sisse R
authors.initials: SR
authors.lastname: Ostrowski
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Deberdt
authors.forename: Pascale
authors.initials: P
authors.lastname: Van Hoydonck
authors.forename: Susan S
authors.initials: SS
authors.lastname: Yonemura
authors.forename: Raymond P
authors.initials: RP
authors.lastname: Goodrich
mesh_terms: D000328:Adult; D000368:Aged; D001792:Blood Platelets; D018592:Cross-Over Studies; D005260:Female; D006487:Hemostasis; D006801:Humans; D008297:Male; D008875:Middle Aged; D017713:Platelet Transfusion / Q000009:adverse effects / Q000379:methods*; D013921:Thrombocytopenia / Q000628:therapy*