Department of Pathology and Laboratory Medicine, Transfusion Service, District of Columbia, United States
Background/Case Studies: Previous studies have demonstrated that Pathogen Reduced Platelets (PR) result in lower 24-hour corrected count increments as compared to non-PR Platelets in Plasma (P-P) and non-Pathogen reduced Platelets in a platelet additive solution (P-PAS). Despite the known decrement in efficacy, the use of PR is advocated as a trade-off to gain increased safety based on the opinion that the decrement is not clinically significant. Studies supporting lack of a clinically significant deficit may have compared mostly Platelets kept in ideal temperature-controlled agitated conditions. A specific comparison of PR and non-PR not locally collected and subjected to real-world shipping conditions has not been reported. A tertiary academic hospital with a bone marrow transplant program dependent on shipped Platelets from outside suppliers transitioned to the indiscriminate use of PR, P-P and P-PAS for all patients except neonates in February 2019.The result of its 5-year experience is described.
Study
Design/Methods: For the first year all Platelets came from the same supplier. In 2024 P-P were received from another supplier. PR were not irradiated. P-P and P-PAS (nonPR) were irradiated and tested with a lateral flow assay for pan-genera bacterial antigens on day of use. Products were selected based on ABO preference and expiration dates. Post-transfusion increments were calculated for every whole unit transfusion to adult non-liver transplant thrombocytopenic patients with documented post-transfusion platelet counts within 24 after the pre-transfusion platelet count for the first 12 months and first quarter of 2024. Monthly average count increments and transfusion failures defined as a post-increment count of less than 10k/uL were compared using spreadsheet statistical software. All transfusion reactions and select cases with poor post-transfusion increments were reviewed.
Results/Findings: Average count increments were inferior with transfusions of 1390 PR (range 6.1-13.2 k/uL) as compared to 563 nonPR (10.5-21.4) which became more pronounced after transitioning to different suppliers for non-PR. The fail rate of PR was also consistently higher except for one month. A seasonal pattern possibly caused by ambient temperature shipping conditions was not identified. (figure 1). Cases of TACO increased after transitioning to PR units. There were 2 cases of possible but unlikely non-severe septic reactions, one involving PR and one P-P. Conclusions: The performance decrement of PR as compared to P-P may be clinically significant for Platelets subjected to real world shipping conditions. Clinicians transfusing PR should be warned to accept lower increments or not check increments when transfusing prophylactically before a procedure. A trial of P-P should be considered in some patients who appear to be possibly immune refractory.
