Abstract
Background: Inflammacheck™ is a new point-of-care (POC) device measuring exhaled breath temperature, humidity, and hydrogen peroxide (H2O2); the latter a marker of oxidative stress in the airways.
Method: Using Inflammacheck™, we assessed levels of H2O2 in exhaled breath condensate (EBC) obtained during 60 seconds of tidal breathing in participants with stable asthma or COPD, and healthy controls. We also explored the effect of patient factors on H2O2 levels (e.g. time of last meal) and assessed device acceptability by questionnaire.
Results: We recruited 177 partcipants (67 asthma [32 GINA 2/3, 34 GINA 4/5], 60 COPD [30 GOLD stages 1/2, 30 GOLD 3/4] and 50 controls. Data from 153 partcipants was analysed. Compared to healthy controls, mean EBC H2O2 levels were significantly higher in participants with COPD (2.55 μM vs 3.17 μM, p<0.001) and asthma (2.55 μM vs 3.11 μM, p=0.008). There was no significant difference between asthma and COPD but levels were higher in severe COPD. Sensitivity analyses confirmed the differences were still significant comparing milder asthma and COPD with healthy controls. A 2.0 μM threshold of H2O2 provided 79% sensitivity (63% specificity) and an 81% positive predicted value for diagnosis of COPD at 53% prevalence. Patient factors were not related to H2O2 levels. All participants agreed the device was easy to use and the test easy to perform.
Conclusion: Compared to healthy controls EBC H2O2 levels were significantly higher in asthma and COPD, and the Inflammacheck™ device may prove a useful POC diagnostic tool.
This study was funded by Asthma UK (AUK-IG-2016-357).
Footnotes
Cite this article as: European Respiratory Journal 2019; 54: Suppl. 63, PA1712.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2019