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Updated: Jul 11, 2026
09:41
Establishment of an Extracellular Acidic pH Culture System
Published on: November 19, 2017
Acidic colonic microclimate--possible reason for false negative hydrogen breath tests.
H Vogelsang1, P Ferenci, S Frotz
11st Department of Gastroenterology and Hepatology, University of Vienna, Austria.
Gut
|January 1, 1988
Summary
Low hydrogen producers can now be accurately diagnosed using hydrogen breath tests. Magnesium sulfate pretreatment overcomes the low hydrogen production, improving diagnostic accuracy for conditions like lactose intolerance.
Area of Science:
- Gastroenterology
- Microbiology
- Clinical Diagnostics
Background:
- Hydrogen (H2) breath tests are crucial for diagnosing gastrointestinal disorders.
- A subset of the population, known as low hydrogen producers, do not exhibit increased breath hydrogen after ingesting non-digestible carbohydrates like lactulose.
- This phenomenon limits the diagnostic utility of H2 breath tests, leading to potential false negatives.
Purpose of the Study:
- To investigate the impact of lactulose and magnesium sulfate (MgSO4) pretreatment on stool pH and hydrogen exhalation in both hydrogen producers and low hydrogen producers.
- To determine if MgSO4 pretreatment can enhance hydrogen production in low hydrogen producers, thereby improving diagnostic sensitivity.
Main Methods:
- Studied 17 hydrogen producers and 12 low hydrogen producers.
- Administered lactulose pretreatment to some hydrogen producers to observe effects on stool pH and H2 exhalation.
- Administered MgSO4 pretreatment to low hydrogen producers before lactulose or lactose loading.
- Monitored stool pH and hydrogen exhalation levels.
Main Results:
- Lactulose pretreatment in hydrogen producers lowered stool pH and decreased H2 exhalation, with some becoming low hydrogen producers.
- MgSO4 pretreatment in low hydrogen producers significantly increased H2 exhalation after lactulose loading, enabling diagnosis.
- In lactose-intolerant low hydrogen producers, MgSO4 pretreatment normalized abnormal lactose H2 breath tests.
- MgSO4 pretreatment did not cause false positives in lactose-tolerant individuals.
Conclusions:
- Colonic pH influences hydrogen production from carbohydrates; lower pH reduces it, while higher pH increases it.
- MgSO4 pretreatment effectively overcomes the lack of hydrogen production in low hydrogen producers.
- This approach enhances the sensitivity of H2 breath tests, preventing false negatives in diagnosing malabsorption and maldigestion.
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