Diagnostic and pathogenetic considerations in transfusion‐related acute lung injury

Abstract

Transfusion-related acute lung injury (TRALI) is an infrequent but life-threatening complication of hemotherapy. The findings in 36 cases are described. The typical clinical presentation includes acute respiratory distress characterized by hypoxemia and fulminant pulmonary edema. The onset is usually within 4 hours of transfusion and is accompanied by hypotension. In most patients (81%), recovery is rapid and complete. In 89 percent of cases, granulocyte or lymphocytotoxic antibodies are found in the serum of the implicated blood product which contained plasma. HLA-specific antibodies were identified in donor serums in 65 percent of cases evaluated. The passive transfer of these antibodies may promote complement activation and subsequent pulmonary injury. TRALI is an important cause of transfusion-associated morbidity and is probably often misdiagnosed. Blood banks need to identify donors whose plasma causes these reactions in order to prevent their recurrence.

Pathophysiology of Acute Lung Injury and the Acute Respiratory Distress Syndrome

“…149,150 Although the presentation of TRALI is similar to ALI/ARDS with acute onset of dyspnea, bilateral infiltrates, and respiratory failure, resolution of TRALI is usually rapid (within 96 hours) and mortality is low (< 10%). 151 TRALI is thought to be mediated primarily by neutrophils. Because TRALI usually occurs in patients undergoing surgery or admitted to the intensive care unit, ''a two-hit'' hypothesis has been proposed for the pathogenesis.…”

“…Clinical risk factors for TRALI that may lead to the first insult include recent surgery, sepsis, trauma, massive transfusions, hematologic malignancies, and cardiac disease. [150][151][152] The second insult is thought to be directly related to the blood product transfusion and leads to activation of the primed neutrophils with resultant pulmonary capillary leakage and noncardiogenic pulmonary edema. There are two primary theories as to the pathophysiology of the neutrophil activation.…”

Présentation de cas : lésion pulmonaire aiguë associée à la transfusion (TRALI) — Un danger net et présent

“…However, there are two predominant hypotheses suggested, both of which result in increased permeability of the pulmonary capillary endothelium and non-cardiogenic, protein-rich pulmonary edema. The first is the antibody-antigen hypothesis 7 wherein donor antibodies in the transfused component recognize cognate antigens on recipient leukocytes. As a result, recipient neutrophils are activated and sequestered within the pulmonary capillaries.…”

“…Even with these favourable outcomes, mortality is still 5-10%. 7,18 According to data reported by the Canadian Blood Services at the Canadian Consensus Conference, mortality from TRALI was 17%. 19 Data from the Food and Drug Administration evaluating transfusion related fatalities from 2001 to 2003, 19 showed that TRALI had emerged as the leading cause of transfusion-related death accounting for 16.3% of transfusion deaths followed by ABO incompatibility and bacterial contamination.…”

Transfusion Related Acute Lung Injury in the Canadian Paediatric Population

“…Two pathophysiological mechanisms have been proposed for TRALI. In the first, named the antibody hypothesis, the pathogenesis of TRALI is related to the infusion of donor antibodies that recognize leukocyte antigens in the transfused host (1,(4)(5)(6)(7)(8)(9)(10). According to the second hypothesis, called the two-hit or twoevent model, neutrophils of recipient origin must be primed by a pre-existing clinical condition.…”