BACKGROUND: Reactive oxygen species function as key metabolites that can impair biological processes. In lung transplantation, severe oxidative stress is expected when ischemia/reperfusion injury, acute allograft rejection, and various infections occur.

CASE REPORT: Two clinical cases in which serial measurements of the oxidative stress response (levels of diacron-reactive oxygen metabolites) were taken during hospitalization using a Free Radical Elective Evaluator are reported. In the first case, a 30-year-old man underwent right single lung transplantation for juvenile pulmonary emphysema. Immunosuppression was maintained using tacrolimus, mycophenolate mofetil, and steroid. The oxidative stress response fluctuated significantly (p<0.01) during the infections caused by bronchial stenosis compared to the stable condition. No acute rejection was seen during hospitalization. In the second case, a 44-year-old woman underwent right single lung transplantation for lymphangioleiomyomatosis. Immunosuppression was maintained by the same regimen as in case 1. The patient’s postoperative course was uneventful, and there was no allograft rejection or infection. The oxidative stress response remained at the non-stress level.

CONCLUSIONS: The oxidative stress response was measured by the levels of diacron-reactive oxygen metabolites in lung transplantation. High oxidative stress responses were seen during exposure to infections. This might become a non-invasive marker of complications after transplantation.

Keywords: Bacterial Infections - microbiology, Bronchitis - microbiology, Bronchoscopy, Lung Transplantation - adverse effects, Postoperative Complications