BACKGROUND:  The effects of transfusion of HLA antibodies to patients with corresponding antigens are not well known.

STUDY DESIGN AND METHODS:  Records of patients who received blood from previous donations of a donor implicated in a case of transfusion‐related acute lung injury (TRALI) were examined. The donor had multiple HLA antibodies reactive with 96 percent of HLA Class I antigens and 88 percent of HLA Class II antigens.

RESULTS:  Among 103 patients (40 with a pretransfusion white blood cell [WBC] count of ≥3.5 × 10⁹/L), 1 patient met criteria for TRALI and had clinical evidence for diffuse alveolar hemorrhage. Among the subset of 55 patients (17 with a pretransfusion WBC count of 3.5 × 10⁹/L) with known HLA types, none developed TRALI even though 54 (98%) had one to five corresponding HLA antigens. In a subgroup of patients four of 62 patients with chest radiographs, developed new or worse bilateral infiltrates with implicated but not control units (p = 0.0625).

CONCLUSION:  Transfusion of HLA antibodies from this donor to nonneutropenic patients did not cause TRALI, but there was a trend of an association with new or worse bilateral pulmonary infiltrates. Further research is needed to determine why transfusion of HLA antibodies to recipients with corresponding antigens causes TRALI in some cases and not in others.