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Transfusion Reactions

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Febrile Nonhemolytic Transfusion Reaction

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Summary

Febrile Non-Hemolytic Transfusion Reaction (FNHTR) is a transfusion reaction caused by host antibodies attacking white blood cells from the donor. This destruction of donor WBCs leads to the release of cytokines, which causes inflammation and fever. In contrast to Acute Hemolytic Transfusion Reaction, there is no hemolysis in FNHTR. And unlike other transfusion reactions that occur during or immediately after the transfusion, FNHTR occurs slower: usually 1-6 hours after the transfusion.

Key Points

  • Febrile Non-Hemolytic Transfusion Reaction (FNHTR)
    • Host antibodies against donor WBCs (or HLA)
      • Classified as a Type II Hypersensitivity Reaction
      • Reaction prevented by leukoreduction of blood products
    • Damaged donor WBCs release cytokines (e.g. TNF-alpha, IL-1, IL-6)
      • Causes general inflammatory symptoms (fever, headaches, flushing, chills)
    • No hemolysis or hemodynamic instability
    • Occurs within 1–6 hours after the transfusion