loading page

Real Time Breath Analysis Using Portable Gas Chromatography for Adult Asthma Phenotypes
  • +4
  • Ruchi Sharma,
  • Wenzhe Zang,
  • Menglian Zhou,
  • Nicole Schafer,
  • Lesa Begley,
  • Yvonne Huang,
  • Xudong Fan
Ruchi Sharma
University of Michigan
Author Profile
Wenzhe Zang
University of Michigan
Author Profile
Menglian Zhou
University of Michigan
Author Profile
Nicole Schafer
University of Michigan
Author Profile
Lesa Begley
University of Michigan
Author Profile
Yvonne Huang
University of Michigan
Author Profile
Xudong Fan
University of Michigan

Corresponding Author:[email protected]

Author Profile

Abstract

Background: Asthma is heterogeneous but accessible biomarkers to distinguish relevant phenotypes remain lacking, particularly in non-Type 2 (T2)-high asthma. Moreover, common clinical characteristics in both T2-high and T2-low asthma (e.g. atopy, obesity, inhaled steroid use) may confound interpretation of putative biomarkers and of underlying biology. This study aimed to identify volatile organic compounds (VOCs) in exhaled breath that distinguish not only asthmatic and non-asthmatic subjects, but also atopic non-asthmatic controls and also by variables that reflect clinical differences among asthmatic adults. Methods: A total of 73 participants (30 asthma, 8 atopic non-asthma, and 35 non-asthma/non-atopic subjects) were recruited for this pilot study. A total of 79 breath samples were analyzed in real-time using automated portable GC developed in-house. GC-MS was also used to identify the VOCs in breath. Machine learning, linear discriminant analysis, and principal component analysis were used to identify the biomarkers. Results: The portable GC was able to complete breath analysis in 30 minutes. A total of 103 VOCs were identified across all samples. A set of 9 biomarkers distinguished asthma and non-asthma/non-atopic subjects, while sets of 2 and of 4 biomarkers, respectively, further distinguished asthmatic from atopic controls, and between atopic and non-atopic controls. Additional unique biomarkers were identified that discriminated subjects by blood eosinophil levels, obese status, inhaled corticosteroid treatment, and also acute upper respiratory illnesses within asthmatic groups. Conclusion: Breath VOC profiling is a clinically accessible tool for asthma diagnosis and phenotyping. A portable GC system is a viable option for rapid assessment in asthma.