Most cell-free DNA in serum samples is generated during the process of clotting in the original collection tube. The concentration of cell-free genomic DNA in fresh plasma is probably the same as that in circulation. Consequently, while serum samples should not be used to monitor the concentration of cell-free DNA in a patient's circulation, serum collected from sample tubes containing clots (i.e., without anticoagulant), 3 to 5 days after the date of phlebotomy, could be useful as a source of DNA with which to screen for posttransfusion microchimerism.

BACKGROUNDPathogen inactivation (PI) is a new approach to blood safety that may introduce additional costs. This study identifies costs that could be eliminated, thereby mitigating the financial impact.STUDY DESIGN AND METHODSCost information was obtained from five institutions on tests and procedures (e.g., irradiation) currently performed, that could be eliminated. The impact of increased platelet (PLT) availability due to fewer testing losses, earlier entry into inventory, and fewer outdates with a 7-day shelf life were also estimated. Additional estimates include costs associated with managing 1) special requests and 2) test results, 3) quality control and proficiency testing, 4) equipment acquisition and maintenance, 5) replacement of units lost to positive tests, 6) seasonal or geographic testing, and 7) health department interactions.RESULTSAll costs are mean values per apheresis PLT unit in USD ($/unit). The estimated test costs that could be eliminated are $71.76/unit and a decrease in transfusion reactions corresponds to $2.70/unit. Avoiding new tests (e.g., Babesia and dengue) amounts to $41.80/unit. Elimination of irradiation saves $8.50/unit, while decreased outdating with 7-day storage can be amortized to $16.89/unit. Total potential costs saved with PI is $141.65/unit. Costs are influenced by a variety of factors specific to institutions such as testing practices and the location in which such costs are incurred and careful analysis should be performed. Additional benefits, not quantified, include retention of some currently deferred donors and scheduling flexibility due to 7-day storage.CONCLUSIONSWhile PI implementation will result in additional costs, there are also potential offsetting cost reductions, especially after 7-day storage licensing.

BackgroundUS FDA draft guidance includes pathogen reduction (PR) or secondary rapid bacterial testing (RT) in its recommendations for mitigating risk of platelet component (PC) bacterial contamination. An interactive budget impact model was created for hospitals to use when considering these technologies.MethodsA Microsoft Excel model was built and populated with base-case costs and probabilities identified through literature search and a survey of US hospital transfusion service directors. Annual costs of PC acquisition, testing, wastage, dispensing/transfusion, sepsis, shelf life, and reimbursement for a mid-sized hospital that purchases all of its PCs were compared for four scenarios: 100% conventional PCs (C-PC), 100% RT-PC, 100% PR-PC, and 50% RT-PC/50% PR-PC.ResultsAnnual total costs were US$3.64, US$3.67, and US$3.96 million when all platelets were C-PC, RT-PC, or PR-PC, respectively, or US$3.81 million in the 50% RT-PC/50% PR-PC scenario. The annual net cost of PR-PC, obtained by subtracting annual reimbursements from annual total costs, is 6.18% above that of RT-PC. Maximum usable shelf lives for C-PC, RT-PC, and PR-PC are 3.0, 5.0, and 3.6 days, respectively; hospitals obtain PR-PC components earliest at 1.37 days.ConclusionThe model predicts minimal cost increase for PR-PC versus RT-PC, including cost offsets such as elimination of bacterial detection and irradiation, and reimbursement. Additional safety provided by PR, including risk mitigation of transfusion-transmission of a broad spectrum of viruses, parasites, and emerging pathogens, may justify this increase. Effective PC shelf life may increase with RT, but platelets can be available sooner with PR due to elimination of bacterial detection, depending on blood center logistics.

kPCR is a high-throughput, sensitive assay that could prove useful in routine quality assurance of the WBC reduction process.