Impact of community respiratory viral infections in urban children with asthma

Publication date: Available online 29 October 2018

Source: Annals of Allergy, Asthma & Immunology

Author(s): Toby C. Lewis, Ediri E. Metitiri, Graciela B. Mentz, Xiaodan Ren, Adam M. Goldsmith, Breanna N. Eder, Kyra E. Wicklund, Megan P. Walsh, Adam T. Comstock, Jeannette M. Ricci, Sean R. Brennan, Ginger L. Washington, Kendall B. Owens, Bhramar Mukherjee, Thomas G. Robins, Stuart A. Batterman, Marc B. Hershenson, the Community Action Against Asthma Steering Committee

Abstract

Background

Upper respiratory tract viral infections cause asthma exacerbations in children. However, the impact of natural colds on asthmatic children in the community, particularly in the high-risk urban environment, is less well-defined.

Objective

We hypothesized that children with high-symptom upper respiratory viral infections have reduced airway function and greater respiratory tract inflammation than children with virus-positive low-symptom illnesses or virus-negative upper respiratory tract symptoms.

Methods

We studied 53 asthmatic children from Detroit, Michigan during scheduled surveillance periods and self-reported respiratory illnesses for one year. Symptom score, spirometry, fraction of exhaled nitric oxide (FeNO) and nasal aspirate biomarkers, viral nucleic acid and rhinovirus (RV) copy number were assessed.

Results

Of 658 aspirates collected, 22.9% of surveillance samples and 33.7% of respiratory illnesses were virus-positive. Compared to the virus-negative asymptomatic condition, children with severe colds (symptom score ≥5) showed reduced forced expiratory flow at 25-75% of the pulmonary volume (FEF25-75), higher nasal mRNA expression of C-X-C motif chemokine ligand (CXCL)-10 and melanoma differentiation-associated protein 5, and higher protein abundance of CXCL8, CXCL10 and C-C motif chemokine ligands (CCL)-2, CCL4, CCL20 and CCL24. Children with mild (symptom score 1-4) and asymptomatic infections showed normal airway function and fewer biomarker elevations. Virus-negative cold-like illnesses demonstrated increased FeNO, minimal biomarker elevation and normal airflow. RV copy number was associated with nasal chemokine levels but not symptom score.

Conclusion

Urban asthmatic children with high-symptom respiratory viral infections have reduced FEF25-75 and more elevations of nasal biomarkers than children with mild or asymptomatic infections, or virus-negative illnesses.

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