Hydrogen sulfide is produced when sulfate-reducing organisms consume hydrogen.
Hydrogen sulfide levels are considered abnormal if they reach ≥3ppm (parts per million) at any point during the breath test.
Trio-smart measures a third fermented gas, hydrogen sulfide (H2S). Which is produced by sulfate-reducing bacteria utilizing H2 to produce H2S. Clinical trials have noted that H2S is associated with diarrhea in patients. In a 2021 study, it was found that healthy subjects had H2S levels of <3.00 ppm. Levels of hydrogen sulfide ≥3.00 ppm are associated with diarrhea and indicative of excess hydrogen sulfide. Higher levels of hydrogen sulfide predict more severe diarrhea.
The "Expected" threshold for H2S is 3.00 ppm. Levels of H2S ≥3.00 ppm at any point during the breath test are considered excess and are associated with diarrhea. A 2022 study demonstrated that in diarrheal IBS patients, H2S ≥2.00 ppm was notably distinguishable from patients with constipation IBS, and was associated with greater H2S- producing bacteria in the gut. For patients with a level ≥ 2.00 ppm, it is recommended to use good clinical judgment to determine the merit of treatment for this result.
References:
Rezaie A, Buresi M, Lembo A, Lin H, McCallum R, Rao S, Schmulson M, Valdovinos M, Zakko S, Pimentel M. Hydrogen and Methane-Based Breath Testing in Gastrointestinal Disorders: The North American Consensus. Am J Gastroenterol. 2017 May;112(5):775-784. doi: 10.1038/ajg.2017.46. Epub 2017 Mar 21. PMID: 28323273; PMCID: PMC5418558.
Pimentel M, Saad RJ, Long MD, Rao SSC. ACG Clinical Guideline: Small Intestinal Bacterial Overgrowth. Am J Gastroenterol. 2020 Feb;115(2):165-178. doi: 10.14309/ajg.0000000000000501. PMID: 32023228.
Singer-Englar, Tahli, Ali Rezaie, Kapil Gupta, Nipaporn Pichetshote, Rashin Sedighi, Eugenia A. Lin, Kathleen Shari Chua and Mark Pimentel. “Sa1219 - Validation of a 4-Gas Device for Breath Testing in the Determination of Small Intestinal Bacterial Overgrowth.” Gastroenterology 154 (2018): n. pag.
Villanueva-Millan MJ, Leite G, Wang J, Morales W, Parodi G, Pimentel ML, Barlow GM, Mathur R, Rezaie A, Sanchez M, Ayyad S, Cohrs D, Chang C, Rashid M, Hosseini A, Fiorentino A, Weitsman S, Chuang B, Chang B, Pichetshote N, Pimentel M. Methanogens and Hydrogen Sulfide Producing Bacteria Guide Distinct Gut Microbe Profiles and Irritable Bowel Syndrome Subtypes. Am J Gastroenterol. 2022 Dec 1;117(12):2055-2066. doi: 10.14309/ajg.0000000000001997. Epub 2022 Sep 6. PMID: 36114762; PMCID: PMC9722381.
Villanueva-Millan MJ, Leite G, Wang J, Morales W, Parodi G, Pimentel ML, Barlow GM, Mathur R, Rezaie A, Sanchez M, Ayyad S, Cohrs D, Chang C, Rashid M, Hosseini A, Fiorentino A, Weitsman S, Chuang B, Chang B, Pichetshote N, Pimentel M. Methanogens and Hydrogen Sulfide Producing Bacteria Guide Distinct Gut Microbe Profiles and Irritable Bowel Syndrome Subtypes. Am J Gastroenterol. 2022 Dec 1;117(12):2055-2066. doi: 10.14309/ajg.0000000000001997. Epub 2022 Sep 6. PMID: 36114762; PMCID: PMC9722381.
H2S
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