Prestorage Leukoreduction
Prestorage leukoreduction is a process that sounds just like its name.
Units of blood products (especially platelets collected by apheresis, also known as "single donor platelets") are filtered or otherwise processed after they are collected (or during the collection process) but before they are put into storage!
OK, to be fair, they are not always leukoreduced before they go into storage, but the process occurs very early in the storage period.The effect of this should be clear: Products that have smaller numbers of white blood cells in them should, in theory, generate fewer pyrogenic cytokines during their stay in storage. Fewer cytokines should mean, in theory, a significantly smaller risk of febrile reactions. In fact, it's more than theory. It really does work, and since centers have started using prestorage leukoreduction (especially for platelet products) we have seen, in general, a decline in febrile reactions.
If I were you, I might be thinking about now that prestorage leukoreduction seems like a lot of trouble (and expense) to go through for a reaction that is best described as a nuisance rather than life-threatening. I would agree with you wholeheartedly IF the leukoreduction was being done only for FNH prevention. However, leukoreduction, both prestorage and pretransfusion, is useful for other things, too. Among them are the following:
- Prevention of Cytomegalovirus (CMV) transmission
- Prevention of HLA alloimmunization in multiply transfused patients
- Possible reduction in the "immunosuppressive effect" of transfusion, with potential decrease in postsurgical infections (and possibly cancer recurrences)
- Possible decrease in bacterial or parasitic contamination
- Possible decrease in reperfusion injury after cardiac bypass
Leukoreduction is also universally mandated in Europe, in part for the above, but also for the (unproven) thought that it might prevent transmission of the vector of variant Creutzfeldt-Jakob Disease. While universal leukoreduction is not mandated in the US, functionally, it is pretty close to universally done.
The next section is a discussion of bacterial contamination, or septic transfusion reactions.
Back to Febrile Nonhemolytic Reactions
Back to Transfusion Reaction Types