Transfusion-Related Acute Lung Injury (TRALI)

Transfusion-Related Acute Lung Injury (TRALI) is a serious condition that can happen after receiving a blood transfusion. It affects the lungs, causing sudden difficulty breathing and low oxygen levels. This happens because the transfusion triggers an immune reaction that damages the small blood vessels in the lungs, leading to fluid buildup and inflammation. People with TRALI often develop symptoms within a few hours after transfusion, including shortness of breath, fever, and low blood pressure. The condition primarily impacts the ability of the lungs to provide oxygen to the body, which can be life-threatening if not recognized quickly.

Transfusion-Related Acute Lung Injury (TRALI) is an acute, non-cardiogenic pulmonary edema occurring within 6 hours of blood product transfusion. It results from an immune-mediated reaction, typically involving donor anti-leukocyte antibodies (anti-HLA or anti-neutrophil antibodies) that activate recipient neutrophils in the pulmonary microvasculature. This activation causes endothelial damage, increased capillary permeability, and subsequent alveolar flooding. TRALI is a leading cause of transfusion-related mortality and is characterized by acute hypoxemia, bilateral pulmonary infiltrates on chest imaging, and absence of circulatory overload or cardiac dysfunction. The syndrome is distinct from transfusion-associated circulatory overload (TACO) and requires prompt recognition to avoid further transfusions that may worsen lung injury.