Respiratory viruses in adults with cystic fibrosis during stable and exacerbations

Abstract

While bacterial infection has been widely studied in cystic fibrosis (CF), evidence of a pathogenic role of viruses is scarce. The aim of this study was to investigate the role of respiratory viruses (RV) in adults with CF during stable state (SS) and exacerbation (EX). A prospective, observational study on adults with CF was conducted at the Adult CF Centre, Policlinico Hospital, Milan, Italy, between 2017 and 2018. DNA and RNA were extracted from sputa collected during SS and at first EX to identify 18 RV (Luminex Nx TAG®). Among 129 patients on SS (median age: 41 yrs; female 42%), RV were detected in 27% including: Rhinovirus/Enterovirus (HRV/EV, 16%), Metapneumovirus (hMPV, 8%), Coronaviruses (CoV, 2%), Adenovirus (1.5%), RSV (1.5%) and Parainfluenza viruses (1.5%). Co-infection of different RV was detected in 5 patients. Prevalence of RV during SS was higher in Autumn/Winter than in Spring/Summer (33% vs. 23%, p=0.218). During the 1-year follow up, 38 patients had exacerbations with RV detection in 42%, including HRV/EV (13%), hMPV (11%), CoV (8%) and Influenza B virus (5.3%). Only 1 patient showed the same viral species in SS and EX, while 9 patients (23.7%) previously negative in SS acquired RV infection in EX. A higher prevalence of RV detection in EX was present among patients with a history of chronic sinusitis (p=0.021) and at least one EX in the previous year (p=0.003). No association between the presence of RV during SS and EX during follow-up was reported (RR 1.24, p=0.46). Prospective studies should investigate persistence of RV in CF sputa as well as the association with clinical outcomes.