A patient with B+ sickle cell disease received 3 units of red blood cells (RBCs) from two O+ donors and developed fever and hypotension after the first unit, consistent with an acute transfusion reaction (ATR). Anti‐B titers in plasma from each O+ donor were markedly elevated and nondiscriminatory. In order to evaluate the potential for the transfused units to produce complement‐mediated hemolysis of B+ RBCs, hemolytic complement testing was performed.
STUDY DESIGN AND METHODS
Plasma from each donor was diluted in veronal buffer and incubated with B+ RBCs, and free hemoglobin was measured by spectrophotometer in the complement hemolysis using human erythrocytes (CHUHE) assay. Peptide inhibitor of complement C1 (PIC1) was used to confirm antibody‐initiated complement pathway activation.
A 96‐fold difference (p = 0.014) in hemolysis was measured between plasma samples from the two O+ donors using the CHUHE assay. The extremely high degree of hemolysis produced by the one plasma was inhibited by PIC1 in a dose‐dependent manner.
These results indicate that hemolytic complement testing with the CHUHE assay can be used to assess the risk of antibody‐initiated, complement‐mediated hemolysis from a transfusion beyond what can be achieved with antibody titers alone.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
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