Update on Chronic Lung Allograft Dysfunction
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Chronic lung allograft dysfunction (CLAD) encompasses a range of pathologies that cause a transplanted lung to not achieve or maintain normal function. CLAD manifests as airflow restriction and/or obstruction and is predominantly a result of chronic rejection. Three distinct phenotypes of chronic rejection are now recognized: bronchiolitis obliterans, neutrophilic reversible allograft dysfunction, and restrictive allograft syndrome. Recent investigations have revealed that each phenotype has a unique pathology and histopathological findings, suggesting that treatment regimens should be tailored to the underlying etiology. CLAD is poorly responsive to treatment once diagnosed, and therefore, the prevention of the factors that predispose a patient to develop CLAD is critically important. Small and large animal models have contributed significantly to our understanding of CLAD, and more studies are needed to develop treatment regimens that are effective in humans.
KeywordsChronic lung allograft dysfunction Bronchiolitis obliterans Bronchiolitis obliterans syndrome Azithromycin responsive allograft dysfunction Neutrophilic reversible allograft dysfunction Restrictive allograft syndrome
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Conflict of Interest
Daniel Kreisel reports a patent (“Induction in tolerance of lung allograft transplantation”) issued to Washington University.
Jason Gauthier and Ramsey Hachem declare no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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