Detection of Pathogenic Bacteria During Rhinovirus Infection is Associated with Increased Respiratory Symptoms and Exacerbations of Asthma

Background—Detection of either viral or bacterial pathogens is associated with wheezing in children, however the influence of both bacteria and virus on illness symptoms has not been described. Objective—We evaluated bacterial detection during peak RV season in children with and without asthma to determine if an association exists between bacterial infection and the severity of RV illnesses. Methods—308 children (166 with asthma, 142 without asthma) ages 4–12 years provided five consecutive weekly nasal samples during September, and scored cold and asthma symptoms daily. Viral diagnostics and quantitative PCR for Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis were performed on all nasal samples. Results—Detection rates were 53%, 17% and 11% for H. influenzae, S. pneumoniae and M. catarrhalis, respectively, with detection of RV increasing the risk of detecting bacteria within the same sample (OR 2.0, 95% CI 1.4–2.7, p<0.0001) or the following week (OR 1.6 (1.1–2.4), p=0.02). In the absence of RV, S. pneumoniae was associated with increased cold symptoms (mean 2.7 (95% CI 2.0–3.5) vs. 1.8 (1.5–2.2), p=0.006) and moderate asthma exacerbations (18% (12%–27%) vs. 9.2% (6.7%–12%), p=0.006). In the presence of RV, S. pneumoniae was © 2014 American Academy of Allergy, Asthma and Immunology. Published by Mosby, Inc. All rights reserved. Corresponding author: Kirsten M. Kloepfer MD, 705 Riley Hospital Drive, Indianapolis, IN 46202. Telephone number (317) 278-7860, Fax number (317) 278-7856, and kloepfer@iupui.edu. Concept and design: JEG, RFL; Analysis and interpretation: KMK, WML, TEP, TK, RFV, MDE, REG, YAB, RFL, JEG; Drafting of manuscript for important intellectual content: KMK, JEG Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Author Manuscript J Allergy Clin Immunol. Author manuscript; available in PMC 2015 May 01. Published in final edited form as: J Allergy Clin Immunol. 2014 May ; 133(5): 1301–1307.e3. doi:10.1016/j.jaci. 2014.02.030. N IH -P A A uhor M anscript N IH -P A A uhor M anscript N IH -P A A uhor M anscript associated with increased moderate asthma exacerbations (22% (16%–29%) vs. 15% (11%–20%), p=0.01). Furthermore, M. catarrhalis detected alongside RV increased the likelihood of experiencing cold and/or asthma symptoms compared to isolated detection of RV (OR 2.0 (1.0– 4.1), p=0.04). Regardless of RV status, H. influenzae was not associated with respiratory symptoms. Conclusion—RV infection enhances detection of specific bacterial pathogens in children with and without asthma. Furthermore, these findings suggest that M. catarrhalis and S. pneumoniae contribute to the severity of respiratory illnesses, including exacerbations of asthma.