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Updated: Jun 14, 2026
A Reversible, Non-invasive Method for Airway Resistance Measurements and Bronchoalveolar Lavage Fluid Sampling in Mice
Published on: April 13, 2010
Airway hyperresponsiveness, peak flow variability and inflammatory markers in non-asthmatic subjects with respiratory
Eythór Björnsson1, Dóra Lúdvíksdóttir, Hans Hedenström
1Department of Allergy and Respiratory Medicine, Landspitali-University Hospital, Reykjavik, Iceland. eythorbj@landspitali.is
Objective:
The aim of this study was to characterise non-asthmatic subjects with asthma-like symptoms during a common cold, particularly in relation to airway hyperresponsiveness (AHR).
Materials And Methods:
Subjects with acute respiratory infections and a group of controls (n = 20 + 20), age 20-65 years, underwent bronchial provocations with methacholine, adenosine and cold air. All were non-smokers and had no history of asthma or heart disease. Those with infection had asthma-like symptoms (>2). Measurements of exhaled nitric oxide (eNO), serum levels of eosinophil cationic protein (ECP), eosinophil peroxidase, myeloperoxidase and human neutrophil lipocalin were made at each provocation. A 17-day symptom and peak flow diary was calculated.
Results:
No differences between the two groups were found, regarding responsiveness to methacholine, adenosine or cold air challenge, as well as the inflammatory markers measured. In the infected group, the mean (standard deviation) ECP was higher in those with AHR to methacholine or cold air [15.7 (6.5) and 11.4 (4.2) microg/L, respectively; P < 0.05]; furthermore, eNO was higher in the infected group [116 (54) and 88 (52) nL/min, respectively; P = 0.055]. The infected group had, at all times, more symptoms and higher peak flow, with a decrease in the symptoms (P = 0.02) and a tendency to change in peak flow variation (P = 0.06).
Conclusion:
AHR does not seem to be the main cause of asthma-like symptoms in adults with infectious wheezing. Peak flow variation and symptom prevalence during the post-infection period may imply airway pathology different from AHR.
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