Clinical Features and C-Reactive Protein as Predictors of Bacterial Exacerbations of COPD

Abstract

Introduction

Identifying predictors of bacterial and viral pathogens in sputum from patients with acute exacerbations of chronic obstructive pulmonary disease (COPD) may help direct management.

Methods

We used data from a trial evaluating a C-reactive protein (CRP) point of care guided approach to managing COPD exacerbations in primary care. We used regression analyses to identify baseline clinical features, including CRP value in those randomized to testing, associated with bacterial, viral or mixed infections, defined by the presence of bacterial and viral pathogens in sputum, detected by culture or polymerase chain reaction (PCR), respectively.

Results

Of 386 participants with baseline sputum samples, 79 (20.5%), 123 (31.9%), and 91 (23.6%) had bacterial, viral/atypical, and mixed bacterial/viral/atypical pathogens identified, respectively. Increasing sputum purulence assessed by color chart was associated with increased odds of finding bacterial and mixed (bacterial and viral/atypical) pathogens in sputum (area under the ROC curve (AUROC) for bacterial pathogens =0.739 (95% CI: 0.670, 0.808)). Elevated CRP was associated with increased odds of finding bacterial pathogens and mixed pathogens but did not significantly increase the AUROC for predicting bacterial pathogens over sputum color alone (AUROC for combination of sputum color and CRP = 0.776 (95% CI: 0.708, 0.843), p for comparison of models = 0.053). We found no association between the presence of sputum pathogens and other clinical or demographic features.

Conclusion

Sputum purulence was the best predictor of sputum bacterial pathogens and mixed bacterial viral/atypical pathogens in patients with COPD exacerbations in our study. Elevated CRP was associated with bacterial pathogens but did not add to the predictive value of sputum purulence.

Journal

Journal ID (nlm-ta): Int J Chron Obstruct Pulmon Dis

Journal ID (iso-abbrev): Int J Chron Obstruct Pulmon Dis

Journal ID (publisher-id): copd

Journal ID (pmc): copd

Title: International Journal of Chronic Obstructive Pulmonary Disease

Publisher: Dove

ISSN (Print): 1176-9106

ISSN (Electronic): 1178-2005

Publication date (Electronic): 01 December 2020

Publication date Collection: 2020

Volume: 15

Pages: 3147-3158

Affiliations

[1 ]Primary Care, Population Sciences and Medical Education, University of Southampton , Southampton, England, UK

[2 ]Centre for Trials Research, Cardiff University , Cardiff, Wales, UK

[3 ]Specialist Antimicrobial Chemotherapy Unit, Microbiology Cardiff, Public Health Wales , Cardiff, Wales, UK

[4 ]School of Population Health and Environmental Sciences, King’s College London , London, England, UK

[5 ]Department of Community Medicine, UIT the Arctic University of Norway , Tromsø, Norway

[6 ]Nuffield Department of Primary Care Health Sciences, University of Oxford , Oxford, England, UK

Author notes

Correspondence: Nick A Francis Primary Care, Population Sciences and Medical Education, University of Southampton, Aldermoor Health Centre , SouthamptonSO16 5ST, UK Email [e-mail]

Article

Publisher ID: 265674

DOI: 10.2147/COPD.S265674

PMC ID: 7718867

Copyright statement: © 2020 Francis et al.

License:

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Page count

Figures: 3, Tables: 6, References: 22, Pages: 12

Funding

This study is a secondary analysis of data collected by a project funded by the NIHR Health Technology Assessment Program (project number 12/33/12). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health. The work was undertaken with the support of: 1) The UK Clinical Research Collaboration (UKCRC) registered Clinical Trials Unit, the Centre for Trials Research, and funding from Health and Care Research Wales and Cancer Research UK, under the auspices of the UKCRC collaboration, is gratefully acknowledged, and; 2) The UK Clinical Research Collaboration (UKCRC) registered University of Oxford Primary Care and Vaccines Clinical Trials Collaborative.

Categories

Subject: Original Research