C-reactive protein concentrations pre- and post-transfusion.

In a prospective study, serum C-reactive protein (CRP) levels were analysed before and after 18 transfusional episodes, using a fluorescence polarization immunoassay. Only patients with a stable CRP value for two consecutive days before transfusion were assessed. Although small rises in CRP concentrations occurred following 55.6% of transfusions, there was no statistically significant difference between pre- and post-transfusion CRP values, and these increases also failed to reach clinical significance. An increase in CRP post-transfusion of greater than 100 mg/l occurred on only one occasion, and was more likely to be due to underlying infection.