Digestive Diseases and Sciences

, Volume 57, Issue 12, pp 3213–3218

Methanobrevibacter smithii Is the Predominant Methanogen in Patients with Constipation-Predominant IBS and Methane on Breath

  • Gene Kim
  • Fnu Deepinder
  • Walter Morales
  • Laura Hwang
  • Stacy Weitsman
  • Christopher Chang
  • Robert Gunsalus
  • Mark Pimentel
Original Article

DOI: 10.1007/s10620-012-2197-1

Cite this article as:
Kim, G., Deepinder, F., Morales, W. et al. Dig Dis Sci (2012) 57: 3213. doi:10.1007/s10620-012-2197-1

Abstract

Purpose

Among irritable bowel syndrome (IBS) patients, breath methane producers overwhelmingly have constipation predominance (C-IBS). Although the most common methanogen in humans is Methanobrevibacter smithii, incidence and type of methanogenic bacteria in C-IBS patients are unknown.

Methods

By use of a questionnaire and lactulose breath testing, subjects with Rome II C-IBS and methane (>3 ppm) were selected (n = 9). The control group included subjects with IBS who had no breath methane (n = 10). Presence of bacterial DNA was assessed in a stool sample of each subject by quantitative-PCR using universal 16S rDNA primer. M. smithii was quantified by use of a specific rpoB gene primer.

Results

M. smithii was detected in both methane and non-methane subjects. However, counts and relative proportion of M. smithii were significantly higher for methane-positive than for methane-negative subjects (1.8 × 107 ± 3.0 × 107 vs 3.2 × 105 ± 7.6 × 105 copies/g wet stool, P < 0.001; and 7.1 ± 6.3 % vs 0.24 ± 0.47 %, P = 0.02 respectively). The minimum threshold of M. smithii resulting in positive lactulose breath testing for methane was 4.2 × 105 copies/g wet stool or 1.2 % of total stool bacteria. Finally, area-under-curve for breath methane correlated significantly with both absolute quantity and percentage of M. smithii in stool (R = 0.76; P < 0.001 and R = 0.77; P < 0.001 respectively).

Conclusions

M. smithii is the predominant methanogen in C-IBS patients with methane on breath testing. The number and proportion of M.smithii in stool correlate well with amount of breath methane.

Keywords

Constipation IBSMethaneMethanogens

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Gene Kim
    • 1
  • Fnu Deepinder
    • 1
  • Walter Morales
    • 1
  • Laura Hwang
    • 1
  • Stacy Weitsman
    • 1
  • Christopher Chang
    • 1
  • Robert Gunsalus
    • 2
  • Mark Pimentel
    • 1
  1. 1.GI Motility Program, Division of GastroenterologyCedars Sinai Medical CenterLos AngelesUSA
  2. 2.Department of MicrobiologyUCLALos AngelesUSA