Breath tests are important for the diagnosis of carbohydrate maldigestion syndromes and small intestinal bacterial overgrowth.
However, standardization is lacking regarding indications for testing, test methodology and interpretation of results.
Dr Ali Rezaie and colleagues reported on a consensus meeting of experts to develop guidelines for clinicians and research.
Pre-meeting survey questions encompassing 5 domains, indications, preparation, performance, interpretation of results, and knowledge gaps, were sent to 17 clinician-scientists, and 10 attended a live meeting.
Using an evidence-based approach, 28 statements were finalized and voted on anonymously by a working group of specialists.
|A rise in hydrogen of ≥20 p.p.m. by 90 min during glucose or lactulose breath tests for small intestinal bacterial overgrowth was considered positive|
|American Journal of Gastroenterology|
Consensus was reached on 26 statements encompassing all 5 domains.
Consensus doses for lactulose, glucose, fructose and lactose breath tests were 10, 75, 25 and 25 g, respectively.
The researchers found that glucose and lactulose breath tests remain the least invasive alternatives to diagnose small intestinal bacterial overgrowth.
The team observed that breath tests are useful in the diagnosis of carbohydrate maldigestion, methane-associated constipation, and evaluation of bloating/gas but not in the assessment of oro-cecal transit.
A rise in hydrogen of ≥20 p.p.m. by 90 min during glucose or lactulose breath tests for small intestinal bacterial overgrowth was considered positive.
The research team noted that Methane levels ≥10 p.p.m. was considered methane-positive.
Small intestinal bacterial overgrowth should be excluded prior to breath tests for carbohydrate malabsorption to avoid false positives.
The team considered a rise in hydrogen of ≥20 p.p.m. from baseline during breath test positive for maldigestion.
Dr Rezaie's team concludes, "Breath tests are a useful, inexpensive, simple and safe diagnostic test in the evaluation of common gastroenterology problems."
"These consensus statements should help to standardize the indications, preparation, performance and interpretation of breath tests in clinical practice and research."