ArticleScientific reports2026
Potential subtype-specific alterations in gut microbiota and branched-chain amino acid metabolism in hydrogen- and methane-predominant small intestinal bacterial overgrowth.
Article in Scientific reports, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
12 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
We aimed to investigate the clinical, microbiome, and metabolomic characteristics of hydrogen (H₂)- and methane (CH₄)-predominant small intestinal bacterial overgrowth (SIBO) subtypes. We retrospectively enrolled adults who underwent standardized lactulose hydrogen–methane breath testing between February 2021 and July 2025. Participants were categorized as Normal, H₂–SIBO, CH₄–SIBO, or mixed H₂/CH₄–SIBO. Clinical characteristics were compared using Kruskal–Wallis tests and chi-square tests. Multivariable logistic regression was used to identify factors independently associated with each SIBO subtype. Expiratory gas profiles (AUC, peak, and mean values) were quantified, and correlations with age and body mass index (BMI) were assessed using Spearman analysis. In a subset of participants, stool samples underwent 16S rRNA gene sequencing and untargeted metabolomic profiling, followed by integrative analyses of microbiota composition, diversity, and metabolic signatures across SIBO subtypes. Among 503 participants, higher serum albumin levels were independently associated with H₂–SIBO, whereas higher fasting glucose was independently associated with CH₄–SIBO. Breath-test profiling indicated that methane parameters, rather than hydrogen, better differentiated SIBO subtypes, and total (H₂ + CH₄) gas output was modestly correlated with age but not BMI. In the exploratory multi-omics subset, fecal microbiota composition and metabolomic signatures differed by subtype; LEfSe identified Bacteroidaceae as a CH₄-SIBO signature and Alcaligenaceae/Acidaminococcaceae as H₂–SIBO signatures. Differential metabolites were enriched in pathways related to branched-chain amino acid biosynthesis, lipid metabolism, and mineral absorption. H₂- and CH₄-predominant SIBO subtypes exhibit distinct clinical correlates and stool microbiome–metabolome profiles. Methane exhalation appears more informative for differentiating subtypes, and age is modestly associated with total expiratory gas volumes. These findings support potential subtype-specific host–microbe metabolic interactions, although the multi-omics results should be interpreted as exploratory.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.