title: The impact of platelet additive solution apheresis platelets on allergic transfusion reactions and corrected count increment (CME).
abstract: BACKGROUND
  Allergic transfusion reaction (ATR) incidence ranges from 1% to 3% of all transfusions. We evaluated the impact of InterSol platelet additive solution (PAS) apheresis platelets (APs) on the incidence of ATRs and the posttransfusion platelet (PLT) increment.
  
  
  METHODS
  This retrospective study evaluated all ATRs among patients at a university hospital that maintained a mixed inventory of PAS APs and non-PAS APs (standard plasma-suspended PLTs). Corrected count increments (CCIs) were calculated for AP transfusions of individuals who received both a PAS and a non-PAS AP transfusion within a 7-day period. Hypothesis testing was performed with chi-square test for dichotomous variables and t tests for continuous variables.
  
  
  RESULTS
  The incidence of ATRs among the non-PAS APs was 1.85% (72 ATRs/3884 transfusions) and 1.01% (12 ATRs/1194 transfusions) for PAS APs (risk ratio [RR], 0.54; 95% confidence interval [CI]=0.30-0.99; p=0.04). However, there was no difference in the incidence of febrile nonhemolytic transfusion reactions between non-PAS APs (incidence, 0.70%; 27/3884) compared to PAS APs (incidence, 0.59%; 7/1194; p=0.69). Among 223 individuals with paired non-PAS and PAS AP transfusions, the mean CCI at 1 to 4 hours after transfusion was 4932 (95% CI, 4452-5412) for non-PAS APs and was lower for PAS APs (CCI, 3766; 95% CI, 3375-4158; p ≤ 0.001). However, there was no significant difference in mean CCI at 12 to 24 hours between non-PAS (CCI, 2135; 95% CI, 1696-2573) and PAS APs (CCI, 1745; 95% CI, 1272-2217; p=0.14).
  
  
  CONCLUSIONS
  PAS APs substantially reduce the number of ATRs. CCIs for PAS APs were lower immediately after transfusion, but not significantly different at 12 to 24 hours.
authors.affiliation: Department of Pathology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Aaron A R
authors.initials: AA
authors.lastname: Tobian
authors.forename: Alice K
authors.initials: AK
authors.lastname: Fuller
authors.forename: Kristin
authors.initials: K
authors.lastname: Uglik
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Tisch
authors.forename: Prabhakar D
authors.initials: PD
authors.lastname: Borge
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Benjamin
authors.forename: Paul M
authors.initials: PM
authors.lastname: Ness
authors.forename: Karen E
authors.initials: KE
authors.lastname: King
mesh_terms: D001781:Blood Component Removal; D001792:Blood Platelets; D006801:Humans; D008962:Models, Theoretical; D017713:Platelet Transfusion / Q000009:adverse effects*; D012189:Retrospective Studies