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Published on: August 7, 2017
The Biomarker Salivary SP-D May Indicate Small Airway Inflammation and Asthma Exacerbation
S Okazaki1, H Murai1, S Kidoguchi2
1Department of Pediatrics, Faculty of Medial Sciences, University of Fukui, Fukui, Japan.
Insights
Salivary surfactant protein (SP) D is elevated in children with asthma and correlates with airway resistance and exacerbation severity. This finding suggests SP-D may be a useful noninvasive biomarker for childhood asthma management.
Area of Science:
- Pediatric Pulmonology
- Biomarker Discovery
- Asthma Pathophysiology
Background:
- Noninvasive, child-friendly biomarkers are crucial for understanding childhood asthma phenotypes.
- Salivary surfactant protein (SP) D is explored as a potential biomarker.
Purpose of the Study:
- To assess the utility of salivary SP-D in evaluating childhood asthma pathophysiology.
- To correlate salivary SP-D levels with lung function and exacerbation severity.
Main Methods:
- Salivary SP-D concentrations and forced oscillation technique (FOT) indexes were measured in 19 healthy controls and 21 asthmatic children.
- Regression models for FOT indexes were derived from healthy controls.
- Correlations between salivary SP-D and FOT predictive values, and exacerbation severity were analyzed.
Main Results:
- Asthmatic children exhibited higher salivary SP-D levels compared to healthy controls.
- In asthmatic children, salivary SP-D correlated with %R5-R20 (peripheral airway resistance).
- Salivary SP-D levels also correlated with asthma exacerbation severity.
Conclusions:
- Salivary SP-D may indicate asthmatic inflammation in peripheral small airways.
- Salivary SP-D shows potential as a useful marker for monitoring childhood asthma exacerbation.
Background:
Noninvasive and child-friendly biomarkers are important tools for understanding the various phenotypes of childhood asthma. Objective: The aim of this study was to examine the usefulness of salivary surfactant protein (SP) D in assessing the pathophysiology of childhood asthma.
Methods:
We measured salivary concentrations of SP-D and forced oscillation technique (FOT) indexes in 19 healthy controls and 21 asthmatic children. Regression equations for the predictive values of FOT indexes were generated from healthy controls. We analyzed the correlations between salivary SP-D concentration and percentages of the predictive values of FOT indexes, as well as the severity of exacerbation.
Results:
We found that salivary SP-D levels were higher in asthmatic children than in healthy controls. In the asthmatic children, salivary SP-D levels correlated with the percentages of predicted differences in resistance between 5 Hz and 20 Hz (%R5-R20), which represented the resistance of peripheral airways, and with the severity of asthma exacerbation.
Conclusions:
Salivary SP-D may reflect asthmatic inflammation in peripheral small airways and may be a useful marker for monitoring the degree of exacerbation in childhood asthma.
