[Current concept of TRALI (transfusion-related acute lung injury)].

It is only 20 years since TRALI was clinically recognized. As it is gradually recognized among Japanese medical community, the number of cases reported is increasing gradually. In the past nine years (1997-2005), Japanese Red Cross confirmed 118 TRALI cases and 38 possible TRALI cases in Japan. Twelve TRALI cases among them occurred during or after anesthesia on the day of operation. Since acute lung injury is caused by multiple pathological factors, it is difficult to identify its main cause as transfusion. Therefore, TRALI has been underdiagnosed and underreported. Several mechanisms have been proposed. Although anti-HLA antibody, anti-HNA antibody, or other immunoreactive substances appear to be involved in developing TRALI, underlying conditions like systemic inflammation may be required for igniting TRALI Although TRALI developed in the operating theater seems to be a small fraction of whole TRALI cases, anesthesiologists should be aware of TRALI, and remember it as one of the causes of acute lung injury.