This article is more than 5 years old. Information may no longer be current.
Community-acquired respiratory viruses a risk factor for chronic lung allograft dysfunction
Community-acquired respiratory viruses causing lower respiratory tract infections are a significant independent risk factor for the development of chronic lung allograft dysfunction, or CLAD, in lung transplant recipients, according to study results.
Although lung transplantation has seen improved short-term graft survival in the past 2 decades, survival beyond 1 year is severely affected by CLAD, which accounts for 20% to 30% of deaths after the first year, researchers said.
“The pathophysiology of CLAD is thought to involve a complex interplay between the lung allograft, anti-donor immunity, and environmental stimuli including infections that elicit direct non-immunological and indirect immune effects,” Joan Gavaldà, MD, PhD, transplant infectious disease physician and coordinator of the antibiotic resistance laboratory Vall d’Hebron Research Institute in Barcelona, and colleagues wrote.
“The most consistent data on the long-term effect of infectious diseases on allograft dysfunction come from viral infections, especially those involving herpes viruses. However, the role of community-acquired respiratory viruses (CARVs) on lung transplant outcomes is still controversial, which is partly due to the fact that CARV infections have not been comprehensively assessed due to several technical limitations in terms of design, case definition and diagnostic procedures.”
Gavaldà and colleagues characterized the association between CARVs and CLAD using multiplex nucleic acid testing (NAT) for 16 different commonly circulating respiratory viruses in a cohort of adult lung transplant recipients undergoing transplantation from September 2009 to September 2011 at Hospital Universitari Vall d’Hebron in Barcelona. Patients were followed from hospital discharge until September 2014 or until death. Additionally, the researchers collected nasopharyngeal swabs from all lung transplant recipients during seasonal changes to study different CARVs according to the season, and from patients with upper respiratory tract infections, lower respiratory tract infections and biopsy-proven acute rejection.
Overall, 98 patients were included in the study with an average follow-up of 3.4 years. Results of the study showed that among these patients, 38 developed CLAD, with 33 diagnoses of bronchitis obliterans-syndrome, two cases of restrictive allograft syndrome and three mixed results. Additionally, 27 patients died, with CLAD related to 13 of the deaths.
According to the study, acute rejection, primary graft dysfunction, positivity for CARVs, CARV-lower respiratory tract infectious disease and cytomegalovirus pneumonitis were significant risk factors for CLAD.
“These results are important and have been intuitively suspected in the past but were clearly revealed through a combination of state-of-the-art multiplex NAT together with a very tight longer-term clinical follow-up of more than 3 years in our study,” Gavaldà and colleagues concluded.
“CARV causing lower respiratory tract infectious disease is an independent risk factor leading to the development of CLAD in lung transplant recipients. Given the important goal of improving the long-term survival of [lung transplant recipients] by reducing the onset of CLAD, future efforts should include earlier CARV diagnosis, as well as the development of antiviral treatment and preventive measures including the development of vaccines against CARVs.” – by Caitlyn Stulpin
Disclosures: The authors report no relevant financial disclosures.