An interventional study of Hydrogen content recording in SIBO and Small Bowel Bacterial Overgrowth Syndrome, sponsored by Johns Hopkins University. Completed at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-05-28.
Sponsored by Johns Hopkins University · Not applicable, Interventional, and Diagnostic
Small intestinal bacterial overgrowth (SIBO) is defined as a condition in which an abnormally high amount of coliform bacteria is present in the small bowel and results in premature anaerobic fermentation of carbohydrates before reaching the colon. Commonly recognized causes include gastric achlorhydria, post-surgical bowel stasis, gastrocolic/coloenteric fistulas, and motility disorders leading to bowel stasis.. The current "gold standard" for the diagnosis of SIBO, is a breath test that measures the concentration of hydrogen in response to lactulose, a carbohydrate that is only metabolized by bacteria. However, its accuracy is only about 50% and therefore it is not a very useful test, leading most physicians to treat these patients empirically based on clinical suspicion alone. The purpose of this study is to evaluate the clinical utility of a portable medical device called AIRE, an over-the-counter, commercially available handheld breath analyzer that measures exhaled hydrogen content.
Small intestinal bacterial overgrowth (SIBO) is defined as a condition in which an abnormally high amount of coliform bacteria is present in the small bowel and results in premature anaerobic fermentation of carbohydrates before reaching the colon. Commonly recognized causes include gastric achlorhydria (i.e. due to longstanding proton pump inhibitor (PPI) use), post-surgical bowel stasis, and gastrointestinal motility disorders leading to bowel stasis. Although SIBO is commonly suspected, a major limitation in the field is the lack of a highly accurate test for SIBO. The current gold standard relies on the demonstration of an early rise in breath hydrogen concentration in response to an orally ingested carbohydrate (commonly, lactulose) but its accuracy is about 50%. This may be because it is a one-time snapshot with an artificial substrate. Further, it has to be performed in a clinic, takes up to 5 hours and is relatively expensive. The purpose of this study is to evaluate the clinical utility of a portable medical device called AIRE, which is a validated and commercially available handheld breathalyzer that measures hydrogen content in the breath and connects via Bluetooth to an associated smartphone application to provide immediate results and visual feedback after use.
11 studies on the registry are indexed under Blind Loop Syndrome; 4 are open to participants now.
This study's enrollment of 45 is close to the median of 48 across 10 interventional studies indexed under Blind Loop Syndrome.
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Exclusion Criteria:
Candidates who, after the screening period are eligible to receive the AIRE device.
Device: Hydrogen content recording
Eligible participants will eat participants' normal, typical diets during the first week of the study. Participants will use the AIRE machine to measure exhaled H2 content before and after two meals each day - the first meal of the day and the last meal of the day. Participants will breathe into the AIRE machine before eating to obtain a baseline value. Once participants have finished eating, participants will breathe into the AIRE machine 30 minutes, 60 minutes, and 90 minutes postprandially. The participants will record participants' food intake and symptoms directly into participants' smartphone via an app that comes with the AIRE device.
Hydrogen Content in Parts Per Million (Ppm)
Exhaled hydrogen (H2) content as measured over a 1-week period by AIRE on the patient's usual diet at home. Mean of one week readings is reported.
Time frame: Up to 1 week
Hydrogen Content in Parts Per Million (Ppm)
For participants who have a positive LHBT test at baseline, antibiotics are prescribed as part of standard of care. These participants will have a repeat AIRE test at 2 weeks post antibiotic treatment.
Time frame: 2 weeks after antibiotic treatment for positive LHBT
Hydrogen Content in Parts Per Million (Ppm)
For participants who have a negative LHBT test at baseline, a repeat AIRE test is done at 1 month after baseline test.
Time frame: One month after negative LHBT
| Milestone | Breath Analyzer |
|---|---|
| Started | 43 |
| Completed | 43 |
| Not completed | 0 |
Exhaled hydrogen (H2) content as measured over a 1-week period by AIRE on the patient's usual diet at home. Mean of one week readings is reported.
| ppm | Breath Analyzer |
|---|---|
| Hydrogen Content in Parts Per Million (Ppm) | 3.5 ± 0.7 |
For participants who have a positive LHBT test at baseline, antibiotics are prescribed as part of standard of care. These participants will have a repeat AIRE test at 2 weeks post antibiotic treatment.
| ppm | Breath Analyzer |
|---|---|
| Hydrogen Content in Parts Per Million (Ppm) | 10.7 ± 1.1 |
For participants who have a negative LHBT test at baseline, a repeat AIRE test is done at 1 month after baseline test.
| ppm | Breath Analyzer |
|---|---|
| Hydrogen Content in Parts Per Million (Ppm) | 8.5 ± 3.1 |
Collected over Up to 1 month of study participation. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Breath Analyzer | 0/43 (0%) | 0/43 (0%) | 0/43 (0%) |
| Age, Categorical(Participants) | Breath Analyzer |
|---|---|
| <=18 years | 0 |
| Between 18 and 65 years | 43 |
| >=65 years | 0 |
| Sex: Female, Male(Participants) | Breath Analyzer |
|---|---|
| Female | 36 |
| Male | 7 |
| Race and Ethnicity Not Collected(Participants) | Breath Analyzer |
|---|
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Ran from Oct 2020 to primary completion in Mar 2025, 53 months.
Results were first posted in May 2025, 2 months after primary completion.
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