title: Human rhinovirus infection during naturally occurring COPD exacerbations.
abstract: Human rhinovirus (HRV) infection is an important trigger of exacerbations of chronic obstructive pulmonary disease (COPD) but its role in determining exacerbation frequency phenotype or the time-course of HRV infection in naturally occurring exacerbations is unknown. Sputum samples from 77 patients were analysed by real-time quantitative PCR for both HRV (388 samples), and Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis (89 samples). Patients recorded worsening of respiratory symptoms on daily diary cards, from which exacerbations were identified. HRV prevalence and load at exacerbation presentation were significantly higher than in the stable state (prevalence 53.3% versus 17.2%, respectively; p<0.001) but 0% by day 35 post-exacerbation. HRV load was higher in patients with cold symptoms (p=0.046) or sore throats (p=0.006) than those without. 73% of bacterium-negative but HRV-positive exacerbations were bacterium-positive by day 14. Patients with HRV detected at exacerbation had a higher exacerbation frequency (interquartile range) of 3.01 (2.02-5.30) per year compared with patients without HRV (2.51 (2.00-3.51)) (p=0.038). HRV prevalence and load increased at COPD exacerbation, and resolved during recovery. Frequent exacerbators were more likely to experience HRV infection. Secondary bacterial infection is common after HRV infection, and provides a possible mechanism for exacerbation recurrence and a potential target for novel therapies.
authors.affiliation: Centre for Respiratory Medicine, University College London, London, UK siobhan.george.10@ucl.ac.uk.
authors.forename: Sîobhán N
authors.initials: SN
authors.lastname: George
authors.affiliation: Centre for Respiratory Medicine, University College London, London, UK.
authors.forename: Davinder S
authors.initials: DS
authors.lastname: Garcha
authors.affiliation: Centre for Respiratory Medicine, University College London, London, UK.
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Mackay
authors.affiliation: Centre for Respiratory Medicine, University College London, London, UK.
authors.forename: Anant R C
authors.initials: AR
authors.lastname: Patel
authors.affiliation: Centre for Respiratory Medicine, University College London, London, UK.
authors.forename: Richa
authors.initials: R
authors.lastname: Singh
authors.affiliation: Centre for Respiratory Medicine, University College London, London, UK.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Sapsford
authors.affiliation: Centre for Respiratory Medicine, University College London, London, UK.
authors.forename: Gavin C
authors.initials: GC
authors.lastname: Donaldson
authors.affiliation: Centre for Respiratory Medicine, University College London, London, UK.
authors.forename: Jadwiga A
authors.initials: JA
authors.lastname: Wedzicha
mesh_terms: D000368:Aged; D001424:Bacterial Infections / Q000150:complications; D005260:Female; D005541:Forced Expiratory Volume; D006193:Haemophilus influenzae; D006801:Humans; D008131:London; D008297:Male; D008875:Middle Aged; D001936:Moraxella catarrhalis; D010850:Picornaviridae Infections / Q000150:complications* / Q000503:physiopathology; D016133:Polymerase Chain Reaction; D015995:Prevalence; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000503:physiopathology / Q000821:virology; D012008:Recurrence; D012229:Rhinovirus; D012907:Smoking; D013147:Spirometry; D013183:Sputum / Q000382:microbiology / Q000821:virology; D013296:Streptococcus pneumoniae; D016896:Treatment Outcome; D014797:Vital Capacity