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Published on: June 11, 2014
Delayed Analysis of Hydrogen-Methane Breath Samples
Marjolein Willemsen1, Kristel Van De Maele1, Yvan Vandenplas1
1Vrije Universiteit Brussel (VUB), UZ Brussel, KidZ Health Castle, Brussels, Belgium.
Insights
Delayed analysis of hydrogen-methane breath tests for diagnosing carbohydrate malabsorption is feasible for hydrogen, but methane analysis may be less reliable. Further research is needed for accurate at-home breath testing.
Area of Science:
- Gastroenterology
- Clinical Diagnostics
- Microbiology
Background:
- Hydrogen-methane breath tests are crucial for diagnosing conditions like carbohydrate malabsorption and small intestinal bacterial overgrowth.
- The COVID-19 pandemic necessitated modifications to breath tests due to their potential to generate aerosols.
- Adapting breath testing for at-home use is essential for patient safety and accessibility.
Purpose of the Study:
- To evaluate the impact of delayed analysis on hydrogen and methane concentrations in breath samples collected during lactose breath tests.
- To assess the feasibility of at-home breath testing with sample storage at room temperature.
- To determine if delayed analysis affects the accuracy of diagnosing carbohydrate malabsorption.
Main Methods:
- Children performed lactose breath tests at home, providing two breath samples at each step.
- One set of samples was analyzed immediately, while the second set was stored at room temperature for 1-4 days.
- Hydrogen and methane concentrations were compared between immediately analyzed and delayed analyzed samples.
Main Results:
- Out of 73 at-home tests, 45.8% were positive for malabsorption.
- Hydrogen concentrations remained stable in samples stored for up to 117 hours.
- Methane concentrations were significantly higher in samples analyzed 1-4 days after collection.
Conclusions:
- Expired hydrogen levels are stable in plastic syringes at room temperature for several days.
- Delayed analysis of methane in breath samples appears less reliable.
- Further investigation is required to understand the implications of delayed analysis on methane and hydrogen concentrations for accurate diagnosis.
Purpose:
Hydrogen-methane breath tests are used to diagnose carbohydrate malabsorption and small intestinal bacterial overgrowth. The COVID-19 pandemic has driven the modification of procedures as breath tests are potentially aerosol-generating procedures. We assessed the effect of delayed analysis of breath samples, facilitating the at-home performance of breath testing.
Methods:
Children provided two breath samples at every step of the lactose breath test. The samples were brought back to the clinic, and one set of samples was analyzed immediately. The second set was stored at room temperature and analyzed 1-4 days later.
Results:
Out of the 73 "double" lactose breath tests performed at home, 33 (45.8%) were positive. The second samples were analyzed 20 to 117 hours after the first samples (41.7±24.3 hours). There was no significant difference in the hydrogen concentration between the first and second sets (Z=0.49, p=0.62). This was not the case for methane, which had a significantly higher concentration in the second breath samples (Z=7.6).
Conclusion:
Expired hydrogen levels remain stable in plastic syringes if preserved at room temperature for several days. On the other hand, the delayed analysis of methane appeared to be less reliable. Further research is needed to examine the impact of delayed analysis on methane and hydrogen concentrations.
