Relationships between WBC and STR and bacterial load and STR. Correlation of WBC count (A) and bacterial load (B) in patients who received bacterially contaminated platelets with presence or absence of STR following transfusion. Bacterial load is shown in cfu/mL. Of the 11 patients who received platelet units with high bacterial loads, 5 developed STRs whereas 6 did not; none of the 9 patients who received platelet units with low bacterial loads developed STRs. STRs were significantly associated with low WBC count (A) and high bacterial loads (B).