Chronic lung allograft dysfunction after lung transplantation

Chronic lung allograft dysfunction (CLAD) remains one of the most important complications after lung transplantation, affecting 50% of patients by 5 years post-transplant. It is a major cause of morbidity and the leading cause of mortality beyond 5 years after the transplantation procedure. CLAD is characterised by a persistent and mostly progressive fall in forced expiratory volume in 1 s (FEV1) of >20% compared with the postoperative best FEV1 and is believed to be the consequence of chronic rejection. In recent years, it has become clear that different phenotypes of CLAD can be identified, based on the pulmonary function evolution and findings on chest imaging. In the present chapter, we will focus on the current definition of CLAD and its phenotypes, risk factors for its development, outcome and possible treatment options.