Longitudinal Study of Cell Free DNA in Lung Transplant

Lung transplant is a viable treatment strategy for many with end-stage lung diseases. Despite advances in both the surgical and medical management, lung transplant recipients experience episodes of allograft insult and injury that lead to dysfunction and ultimately contribute to graft failure. The primary noninvasive tool for monitoring the lung allograft, pulmonary function testing, is neither sensitive nor specific for lung allograft injury which makes the management of lung transplant recipients particularly challenging. A decline in pulmonary function tests prompts invasive procedures such as bronchoscopy with transbronchial lung biopsy to diagnose the cause of allograft injury, although this, too, is not 100% sensitive, and oftentimes patients are treated empirically for rejection when no other etiology for lung function decline is identified. Empiric treatment prompted by extrapulmonary drivers of decline in lung function may result in inappropriate exposure to risks of augmented immunosuppression. The purpose of this study is to determine to what extent monitoring of donor-derived cell free DNA in lung transplant recipients can be used as a marker of lung injury and stability.