Impact of Oral-Cecal Transit Time on the Interpretation of Lactulose Breath Tests After RYGB: a Personalized Approach to the Diagnosis of SIBO

  • Pichamol Jirapinyo
  • Tracy T. Makuvire
  • William Y. Dong
  • Walter W. Chan
  • Christopher C. ThompsonEmail author
Original Contributions



Traditionally, small intestinal bacterial overgrowth (SIBO) is diagnosed when there is an early peak in breath hydrogen or methane. Given unclear intestinal transit time in Roux-en-Y gastric bypass (RYGB) patients, it is unknown if the traditional approach at diagnosing SIBO is adequate in this patient population.


To assess oral-cecal transit time (OCTT) and its impact on the interpretation of breath tests in the diagnosis of SIBO in patients with RYGB.


This study was a retrospective review of prospectively collected data on RYGB patients who underwent testing for SIBO using lactulose breath test (LBT) with or without small bowel follow-through (SBFT) to assess OCTT. Outcomes of SIBO test based on LBT alone versus LBT with OCTT were compared using a chi-squared test.


Sixty-two of the 151 RYGB patients who underwent LBT underwent an additional SBFT to assess OCTT. Median OCTT was 60 min. Of these, 59.7% had OCTT shorter than 90 min. Based on LBT alone, 36/62 patients (58.1%) were classified as positive SIBO. When LBT results were combined with OCTT, 26/36 patients (72.2%) had hydrogen or methane rise within OCTT, suggesting 27.8% false positive rate. Patients with true positive SIBO based on LBT and OCTT had a higher response rate to antibiotics compared to those with false positive SIBO (78.3% vs. 33.3%, p = 0.03).


A personalized approach of combining LBT with SBFT to assess OCTT may improve the accuracy of SIBO testing and enhance clinical outcomes in patients with RYGB.


RYGB Bariatric SIBO Bacterial overgrowth Breath test Bloating Abdominal pain 


Author Contributions

Pichamol Jirapinyo: Study design, data collection and analysis, drafting and revision of the manuscript

Tracy T. Makuvire: Data collection

William Y. Dong: Data collection

Walter W. Chan: Study design, study analysis

Christopher C. Thompson: Study design, critical revision of the manuscript

Compliance with Ethical Standards

The study was approved by the Institutional Review Board (IRB) (IRB Protocol Number, 2013P001597).

Conflict of Interest

The authors declare that they have no conflict of interest.

Ethical Approvement Statement

For this type of study, formal consent is not required.

Informed Consent Statement

Does not apply.


  1. 1.
    Sabate J-M, Coupaye M, Ledoux S, et al. Consequences of small intestinal bacterial overgrowth in obese patients before and after bariatric surgery. Obes Surg. 2017;27:599–605.CrossRefGoogle Scholar
  2. 2.
    Dukowicz AC, Lacy BE, Levine GM. Small intestinal bacterial overgrowth. Gastroenterol Hepatol. 2007;3:112–22.Google Scholar
  3. 3.
    Armbrecht U, Lundell L, Lindstedt G, et al. Causes of malabsorption after total gastrectomy with Roux-en-Y reconstruction. Acta Chir Scand. 1988;154:37–41.PubMedGoogle Scholar
  4. 4.
    Romagnuolo J, Schiller D, Bailey RJ. Using breath tests wisely in a gastroenterology practice: an evidence-based review of indications and pitfalls in interpretation. Am J Gastroenterol. 2002;97:1113–26.CrossRefGoogle Scholar
  5. 5.
    Quercia I, Dutia R, Kotler DP, et al. Gastrointestinal changes after bariatric surgery. Diabetes Metab. 2014;40:87–94.CrossRefGoogle Scholar
  6. 6.
    Morinigo R, Moize V, Musri M, et al. Glucagon-like peptide-1, peptide YY, hunger, and satiety after gastric bypass surgery in morbidly obese subjects. J Clin Endocrinol Metab. 2006;91:1735–40.CrossRefGoogle Scholar
  7. 7.
    Wang G, Agenor K, Pizot J, et al. Accelerated gastric emptying but no carbohydrate malabsorption 1 year after gastric bypass surgery (GBP). Obes Surg. 2012;22:1263–7.CrossRefGoogle Scholar
  8. 8.
    Abidi WM, Chan WW, Thompson CC. Mo1285 breath testing for small intestinal bacterial overgrowth in Roux-en-Y gastric bypass patients: the importance of orocecal transit time. Gastroenterology. 2016;150:S688–9.CrossRefGoogle Scholar
  9. 9.
    Rezaie A, Buresi M, Lembo A, et al. Hydrogen and methane-based breath testing in gastrointestinal disorders: the North American consensus. Am J Gastroenterol. 2017;112:775–84.CrossRefGoogle Scholar
  10. 10.
    Petrone P, Sarkisyan G, Fernández M, et al. Small intestinal bacterial overgrowth in patients with lower gastrointestinal symptoms and a history of previous abdominal surgery. Arch Surg Chic Ill 1960. 2011;146:444–7.Google Scholar
  11. 11.
    Kotler DP, Sherman D, Bloom SR, Holt PR Malnutrition after gastric surgery. Association with exaggerated distal intestinal hormone release. Dig Dis Sci 1985;30:193–199.Google Scholar
  12. 12.
    Franco DL, Disbrow MB, Kahn A, et al. Duodenal aspirates for small intestine bacterial overgrowth: yield, PPIs, and outcomes after treatment at a tertiary academic medical center. Gastroenterol Res Pract. 2015;2015:971582.CrossRefGoogle Scholar
  13. 13.
    Corazza GR, Menozzi MG, Strocchi A, et al. The diagnosis of small bowel bacterial overgrowth. Reliability of jejunal culture and inadequacy of breath hydrogen testing. Gastroenterology. 1990;98:302–9.CrossRefGoogle Scholar
  14. 14.
    Welkos SL, Toskes PP, Baer H. Importance of anaerobic bacteria in the cobalamin malabsorption of the experimental rat blind loop syndrome. Gastroenterology. 1981;80:313–20.PubMedGoogle Scholar
  15. 15.
    Shindo K, Machida M, Koide K, et al. Deconjugation ability of bacteria isolated from the jejunal fluid of patients with progressive systemic sclerosis and its gastric pH. Hepatogastroenterology. 1998;45:1643–50.PubMedGoogle Scholar
  16. 16.
    Wanitschke R, Ammon HV. Effects of dihydroxy bile acids and hydroxy fatty acids on the absorption of oleic acid in the human jejunum. J Clin Invest. 1978;61:178–86.CrossRefGoogle Scholar
  17. 17.
    Russell RM, Krasinski SD, Samloff IM, et al. Folic acid malabsorption in atrophic gastritis. Possible compensation by bacterial folate synthesis. Gastroenterology. 1986;91:1476–82.CrossRefGoogle Scholar
  18. 18.
    Camilo E, Zimmerman J, Mason JB, et al. Folate synthesized by bacteria in the human upper small intestine is assimilated by the host. Gastroenterology. 1996;110:991–8.CrossRefGoogle Scholar
  19. 19.
    Shah SC, Day LW, Somsouk M, et al. Meta-analysis: antibiotic therapy for small intestinal bacterial overgrowth. Aliment Pharmacol Ther. 2013;38:925–34.CrossRefGoogle Scholar
  20. 20.
    Mearin F, Balboa A, Zárate N, et al. Placebo in functional dyspepsia: symptomatic, gastrointestinal motor, and gastric sensorial responses. Am J Gastroenterol. 1999;94:116–25.CrossRefGoogle Scholar
  21. 21.
    Allescher HD, Böckenhoff A, Knapp G, et al. Treatment of non-ulcer dyspepsia: a meta-analysis of placebo-controlled prospective studies. Scand J Gastroenterol. 2001;36:934–41.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Division of Gastroenterology, Hepatology and EndoscopyBrigham and Women’s HospitalBostonUSA
  2. 2.Harvard Medical SchoolBostonUSA
  3. 3.Stony Brook UniversityStony BrookUSA

Personalised recommendations