0000000000280476
AUTHOR
Eleftherios C. Vamvakas

 Interventions to Reduce Platelet Prophylactic Transfusions in Patients with Hypoproliferative Thrombocytopenia: Providing Patients with the Full Benefit
SUMMARY To reduce the infectious and immunologic complications of platelet transfusions in patients with hypoproliferative thrombocytopenia, three interventions have aimed to decrease the number of prophylactic platelet transfusions received by such patients for the prevention of bleeding. These are the reduction of the platelet count threshold triggering prophylactic transfusion, the administration of low-dose (as opposed to standard-dose) platelet transfusions, and the administration of therapeutic (as opposed to prophylactic) platelet transfusions. We demonstrate that—in terms of absolute risk reduction in all infectious and some immunologic complications of transfusion— patients can ben…

 Donor Exposures in Recipients of Pooled Platelet Concentrates: a Case-Study in Arithmetic, Logic, "Expert Opinion", and the "Peer Review" Process
Advocacy for single-donor (rather than pooled) platelets has been based on the absolute increase in the risk of transfusion-transmitted infections (TTIs) from pooled (rather than single-donor) platelets in the population of platelet transfusion recipients. A recent study published in a prestigious medical journal advocated for pooled (rather than single-donor) platelets based on the relative increase in the risk of TTIs from pooled (rather than single-donor) platelets in patients transfused with any blood component. If this policy recommendation for use of pooled (rather than single-donor) platelets were followed in the US, there would be an annual increase in the risk of TTIs by 15-20 reci…

 Consistency and Proportionality in Policy Decision-Making in Blood Safety: the Case for an All-Apheresis Platelet Supply in Germany
SUMMARY Recently, German investigators presented the first mathematical model finding a significant increase in the risk of HIV, HCV, and HBV transmission when pools of 4 whole-blood-derived buffy-coat platelets, rather than 1 singledonor (apheresis) component, are used to provide one platelet dose. Based, in both cases, on mathematical models employing the incidence/window-period method, the relative risk of transmission from pooled versus apheresis platelets (2.2 or 2.75 for HIV, 2.7 or 3.375 for HCV, and 3.2 or 4.0 for HBV, with pools of 4 or 5 concentrates, respectively) is similar to the difference in risk before (versus after) introduction of HIV-1 and HCV RNA screening. The absolute …
Effects of pathogen reduction systems on platelet microRNAs, mRNAs, activation, and function
Pathogen reduction (PR) systems for platelets, based on chemically induced cross-linking and inactivation of nucleic acids, potentially prevent transfusion transmission of infectious agents, but can increase clinically significant bleeding in some clinical studies. Here, we documented the effects of PR systems on microRNA and mRNA levels of platelets stored in the blood bank, and assessed their impact on platelet activation and function. Unlike platelets subjected to gamma irradiation or stored in additive solution, platelets treated with Intercept (amotosalen + ultraviolet-A [UVA] light) exhibited significantly reduced levels of 6 of the 11 microRNAs, and 2 of the 3 anti-apoptotic mRNAs (B…