Chronic and long-term complications after lung transplant: a narrative review

Background: The purpose of this article is to provide a current literature overview of long-term complications after lung transplantation (LT) which commonly affect graft survival. Long-term survival after LT is poor compared to that of other solid organ transplants. Understanding entities which influence graft function will lay a platform for new research into prevention and treatment and hopefully translate to improved survival. Methods: Narrative overview of literature retrieved from searches of computerized databases (predominantly PubMed from 1990 to 2020) and other authoritative texts. The review focused primarily on terms related to chronic lung allograft dysfunction and infections which most commonly lead to graft failure, with an emphasis on current recommendations. Results: One-year survival after LT has improved significantly. Median survival worldwide is now 6.2 years (improved from 4.3 in the era 1990-1998) and if recipients survive the first year, median survival is 8.3 years. Median survival worldwide over the period 2009-2016 is 6.5 years. Despite these improvements, long-term survival after LT continues to lag survival after other solid organ transplants. Long-term medical complications after LT are diverse and encompass predominantly events related to infections, chronic rejection, malignancy, or sequelae of large airway complications. Complications related to onset and progression of chronic lung allograft dysfunction (CLAD) translates to poor long-term survival and patients remain at risk for infections throughout their post-transplant lives. Furthermore, infection is often a risk factor for CLAD and vice versa. This review provides a brief overview of these entities. Conclusions: Long-term complications of infection and chronic graft failure continue to limit survival after LT. The last two decades have cast significant light on the etiology and pathogenesis of chronic graft failure.