- Email: [email protected]
Su1428 The Effect of Small Intestinal Bacterial Overgrowth on Lactose Intolerance Breath Test in Subjects With Non-Irritable Bowel Syndrome
AGA Abstracts
baseline, both the control (1.35±0.67) and CdtB group (1.54±0.67) had equal titers of antiCdtB (P=0.54). However, at the conclusion of the study, the CdtB group titer was greater (3.38±0.22) compared to the control group (1.97±1.00) (P<0.01). In the ileum, 9 of 10 rats in the CdtB group had total bacterial counts greater than 1.9x107 compared to only 4 in the control group (P=0.029 by Fisher's exact test). The opposite was seen with M. smithii such that lower stratified counts were seen in the ileum among CdtB immunized rats (P= 0.03). Among the rats with the higher stratified bacterial counts, their stool was wetter with 63±3% water compared to lower total bacterial (61±2%) (P=0.08). Based on a Spearman rank correlation, the level of total bacteria had a significant inverse relationship with ckit levels in the ileal wall (R=-0.35, P<0.05). Conclusions: Cytolethal distending toxin B immunization alone results in changes in stool wet weight and ileal microbial populations that depend on c-kit levels. These data begin to substantiate previous data suggesting that CdtB is important in the development of bowel changes in post-infectious IBS through toxin induced immune mediated events.
lactulose followed by a further rise of greater than 15 ppm within 180 minutes was a positive test for SIBO; 2) The new Proposed Criteria for a positive result: a hydrogen concentration of greater than 20 ppm from a baseline less than 10 ppm by either 60 or 80 minutes after ingestion of 10 g lactulose followed by a further rise of greater than 15 ppm during the 180 minutes test. Patients ingested 10 grams of lactulose in 120 cc of water after two baseline breath samples were collected followed by breath samples obtained every 20 minutes for 180 minutes. All patients who had a baseline hydrogen or methane greater than or equal to 10 ppm at baseline were excluded. The LBT equipment was a Quintron BreathTracker SC Digital Microlyzer with carbon dioxide calibration. All LBT analysis were performed by two investigators independently (RM, JS). Results: 153 LBTs were analyzed from a university motility center from 2011 to 2013 for the indication of suspected SIBO. Symptoms included gas, bloating, abdominal distension, diarrhea, constipation, abdominal pain, nausea and vomiting. Mean age was 54.6 years (range 23 to 86) and 84.3% were female. Based on the Current Guidelines protocol, 40 (26.1%) patients tested positive by 100 minutes. Based on the Proposed Criteria protocol, 18 (11.8%) tested positive by 60 minutes and 28 (18.3%) by 80 minutes. All patients who tested positive had a subsequent second peak of greater than 15 ppm above the first noted peak. The percentage of positive LBTs at 60 and 80 minutes was significantly less than for the 100 minutes criteria (p < 0.05). Conclusions: 1) New criteria to interpret the LBT based on the reality of lactulose cecal arrival times are required; 2) Our proposal that the first peak increase in hydrogen occur by 60 minutes is a conservative recommendation to increase the specificity of LBT for SIBO; 3) Future studies combining small bowel culture with LBT data will help clarify its accuracy for SIBO.
Su1425 For Glucose Breath Testing to Identify Small Bowel Bacterial Overgrowth, Addition of Methane Detection Has a Low Yield Emery C. Lin, Benson T. Massey BACKGROUND AND AIM: Breath testing is a commonly used test for the diagnosis of small bowel bacterial overgrowth (SBBO). A theoretical concern for hydrogen breath testing with both lactulose and glucose is missing methane production from SBBO. However, methane production normally occurs during colonic fermentation and this is not prevented by standard dietary restrictions used in most breath test protocols. Thus, strict criteria for an appropriately timed rising methane curve are necessary to consider methane values as potentially indicative of SBBO. The aim of this study is to assess the increased yield for diagnosis of SBBO using methane measurements during glucose breath testing, particularly with the use of concurrent scintigraphy for equivocal cases. METHODS: A total of 535 consecutive glucose breath test studies performed at the Medical College of Wisconsin between January 2003 and August 2013 were retrospectively reviewed. The tests were performed with gas chromatography. Methane and hydrogen levels were tracked every 15 minutes over a period of 3 hours. Results based on rise in both hydrogen and methane were classified separately as follows: 1) Negative study - no steady rise by >15ppm within first 90 minutes, 2) Definitive SBBO - initial rise at 15 minutes, with steady rise by >15ppm over baseline within 90 minutes, and no prior surgery 3) Indeterminate (pattern potentially consistent with SBBO) - all other cases. If concurrent scintigraphy was available, indeterminate studies were further classified into SBBO (rise prior to arrival of glucose load at the cecum) or rapid transit (rise after glucose load arrives at the cecum). Changes in classification based on the use of methane criteria in addition to hydrogen criteria were assessed. RESULTS: Results of classification via both hydrogen and methane criteria are shown in Table 1. 64% of all patients studied were methane producers (>3ppm), but only 9 patients showed a pattern of methane rise potentially consistent with SBBO (1 definitive SBBO, 8 indeterminate). Of the 4 indeterminate patients whom had concurrent scintigraphy, none were consistent with SBBO and 4 were consistent with rapid transit. Addition of methane criteria to hydrogen criteria identified 1 new case of SBBO, but in the absence of scintigraphy could potentially have identified 2 new false positive (rapid transit) cases. CONCLUSION: While methanogenic bacteria are prevalent, the pattern of methane production during glucose breath testing is more consistent with on-going colonic fermentation than SBBO in the vast majority of patients. Although methane breath testing rarely may detect cases of SBBO that would otherwise be undetected by hydrogen breath testing, it can also result in new false positive results in patients with rapid transit. Classification of studies via hydrogen and methane criteria
Su1427 Demographic and Clinical Factors Associated With Small Intestinal Bacterial Overgrowth (SIBO) Carolyn Newberry, Oleg Shulik, Ann Tierney, Octavia E. Pickett-Blakely BACKGROUND: Small Intestinal Bacterial Overgrowth (SIBO) is increasingly diagnosed in individuals presenting for evaluation of gastrointestinal symptoms. Although there are well recognized gastrointestinal conditions predisposing patients to SIBO, there is a paucity of literature examining other factors that may contribute to its development. In particular, studies evaluating the association between age, sex, and body mass index (BMI) and SIBO are few. Therefore, the aim of this study is investigate whether there is an association between demographic and clinical factors and the diagnosis of SIBO. METHODS: We conducted a retrospective, cross-sectional analysis of a large university-based population cohort utilizing our institutional electronic medical record. The study sample included all patients who underwent lactulose hydrogen breath testing (LHBT) between 6/1/2009 and 6/1/2013. Chart review was performed to obtain clinical data needed for the analysis. Patients were excluded from the analysis if data was missing. The primary outcome variable was LHBT result which was designated as negative, positive, or equivocal. The predictor variables were age, sex, and BMI. Multinomial logistic regression analysis was performed with models adjusted for proton pump inhibitor (PPI) use, history of gastroparesis, and history of gastrointestinal surgery. RESULTS: The study sample included 797 patients. Breath test results were negative, positive, or equivocal in 37%, 51%, and 12% respectively. Among the three LHBT groups, there was no significant difference in the mean age, sex (% female), or mean BMI. In the adjusted analysis there was an increased odds of having a positive LHBT compared with a negative LHBT in females as age increased [OR 0.90, 95% CI: 0.821- 0.987]. However, this finding was not observed in males [OR 0.974, 95% CI: 0.864- 1.098]. When examined alone, female sex was not associated with LHBT result. Although there was no statistically significant association observed between BMI and positive LHBT compared with a negative breath test, the result approached statistical significance [OR 0.976, CI: 0.951- 1.001]. CONCLUSIONS: This analysis shows that although there was not a significant association of sex and LHBT alone, there was an association between a positive LHBT result and increasing age in females but not males. Additionally, contrary to previous reports of increased frequency of SIBO in obese patients, in this study BMI was not statistically associated with a positive LHBT result, but closely approached clinical significance. Additional studies examining the association between demographic and clinical factors such as BMI and SIBO are needed to confirm these findings. However, clinicians should have a high index of suspicion to test for SIBO in older women as this subgroup may be at higher risk. Su1428 The Effect of Small Intestinal Bacterial Overgrowth on Lactose Intolerance Breath Test in Subjects With Non-Irritable Bowel Syndrome Tsachi Tsadok Perets, Dalal Hamouda, Einav Shporn, Yaron Niv, Ram Dickman Background: Irritable bowel syndrome (IBS) is a common chronic disorder of unclear origin characterized by abdominal pain, bloating and altered bowel features. In IBS patients with small intestinal bacterial overgrowth (SIBO), breath tests for lactose intolerance (LI) may be falsely abnormal. Aim: To assess the influence of SIBO on the results of breath tests to lactose in non-IBS subjects. Methods: A total of 348 non-IBS subjects with suspected LI underwent SIBO and LI testing by hydrogen breath test (HBT). We used 15 gr of lactulose dissolved in 50 ml of water, and 50 gr of lactose dissolved in 250 ml of water for the SIBO and LI-HBTs, respectively. The test result was considered positive when there was a rise above baseline in hydrogen concentration of 10 parts per million (ppm) for SIBO, and 20 ppm for LI. Results: Of the 348 subjects, 90 (26%) were negative for both SIBO and LI, 59 (17%) were positive for SIBO and negative for LI, 98 (28%) were negative for SIBO and positive for LI and 101 (29%) were positive for both SIBO and LI. Of those 101 SIBO and LI positive patients, 82 (81%) had an increase of hydrogen measurement above threshold between 30-90 minutes during their LI-HBT, implying SIBO. In contrast, subjects who were negative for SIBO and positive for LI showed an increase of hydrogen measurement above threshold between 120-180 minutes during their LI-HBT. Conclusions: Small intestinal bacterial overgrowth may affect the results of breath tests for LI in non-IBS subjects. We suggest that symptomatic patients with or without IBS should undergo SIBO testing and eradication if diagnosis was positive, prior to LI-HBT evaluation.
Su1426 Re-Evaluation of the Interpretation of the Lactulose Breath Test in the Diagnosis of Small Intestinal Bacterial Overgrowth - Guideline to Enhance Specificity Joseph Sunny, Cesar J. Garcia, Richard W. McCallum Introduction: Current guidelines for interpreting a positive lactulose breath test (LBT) in diagnosing small intestinal bacterial overgrowth (SIBO) rely on an initial peak value of hydrogen within 100 minutes of lactulose ingestion with a second peak before 180 minutes. Scintigraphic transit testing for lactulose by us and others indicates that mean cecal arrival time varied from 75 to 100 minutes and individual arrival times ranged from 30 to 139 minutes. Therefore, our goal was to propose new criteria for analysing the LBT for SIBO to overcome false positives which represent arrival of lactulose in the cecum. Methods: LBTs from our referral center were interpreted utilizing the following rules: 1) The Current Guidelines: a hydrogen concentration of greater than 20 parts per million (ppm) from a baseline less than 10 ppm achieved by 100 minutes after ingestion of 10 grams (g) of
AGA Abstracts
S-466
baseline, both the control (1.35±0.67) and CdtB group (1.54±0.67) had equal titers of antiCdtB (P=0.54). However, at the conclusion of the study, the CdtB group titer was greater (3.38±0.22) compared to the control group (1.97±1.00) (P<0.01). In the ileum, 9 of 10 rats in the CdtB group had total bacterial counts greater than 1.9x107 compared to only 4 in the control group (P=0.029 by Fisher's exact test). The opposite was seen with M. smithii such that lower stratified counts were seen in the ileum among CdtB immunized rats (P= 0.03). Among the rats with the higher stratified bacterial counts, their stool was wetter with 63±3% water compared to lower total bacterial (61±2%) (P=0.08). Based on a Spearman rank correlation, the level of total bacteria had a significant inverse relationship with ckit levels in the ileal wall (R=-0.35, P<0.05). Conclusions: Cytolethal distending toxin B immunization alone results in changes in stool wet weight and ileal microbial populations that depend on c-kit levels. These data begin to substantiate previous data suggesting that CdtB is important in the development of bowel changes in post-infectious IBS through toxin induced immune mediated events.
lactulose followed by a further rise of greater than 15 ppm within 180 minutes was a positive test for SIBO; 2) The new Proposed Criteria for a positive result: a hydrogen concentration of greater than 20 ppm from a baseline less than 10 ppm by either 60 or 80 minutes after ingestion of 10 g lactulose followed by a further rise of greater than 15 ppm during the 180 minutes test. Patients ingested 10 grams of lactulose in 120 cc of water after two baseline breath samples were collected followed by breath samples obtained every 20 minutes for 180 minutes. All patients who had a baseline hydrogen or methane greater than or equal to 10 ppm at baseline were excluded. The LBT equipment was a Quintron BreathTracker SC Digital Microlyzer with carbon dioxide calibration. All LBT analysis were performed by two investigators independently (RM, JS). Results: 153 LBTs were analyzed from a university motility center from 2011 to 2013 for the indication of suspected SIBO. Symptoms included gas, bloating, abdominal distension, diarrhea, constipation, abdominal pain, nausea and vomiting. Mean age was 54.6 years (range 23 to 86) and 84.3% were female. Based on the Current Guidelines protocol, 40 (26.1%) patients tested positive by 100 minutes. Based on the Proposed Criteria protocol, 18 (11.8%) tested positive by 60 minutes and 28 (18.3%) by 80 minutes. All patients who tested positive had a subsequent second peak of greater than 15 ppm above the first noted peak. The percentage of positive LBTs at 60 and 80 minutes was significantly less than for the 100 minutes criteria (p < 0.05). Conclusions: 1) New criteria to interpret the LBT based on the reality of lactulose cecal arrival times are required; 2) Our proposal that the first peak increase in hydrogen occur by 60 minutes is a conservative recommendation to increase the specificity of LBT for SIBO; 3) Future studies combining small bowel culture with LBT data will help clarify its accuracy for SIBO.
Su1425 For Glucose Breath Testing to Identify Small Bowel Bacterial Overgrowth, Addition of Methane Detection Has a Low Yield Emery C. Lin, Benson T. Massey BACKGROUND AND AIM: Breath testing is a commonly used test for the diagnosis of small bowel bacterial overgrowth (SBBO). A theoretical concern for hydrogen breath testing with both lactulose and glucose is missing methane production from SBBO. However, methane production normally occurs during colonic fermentation and this is not prevented by standard dietary restrictions used in most breath test protocols. Thus, strict criteria for an appropriately timed rising methane curve are necessary to consider methane values as potentially indicative of SBBO. The aim of this study is to assess the increased yield for diagnosis of SBBO using methane measurements during glucose breath testing, particularly with the use of concurrent scintigraphy for equivocal cases. METHODS: A total of 535 consecutive glucose breath test studies performed at the Medical College of Wisconsin between January 2003 and August 2013 were retrospectively reviewed. The tests were performed with gas chromatography. Methane and hydrogen levels were tracked every 15 minutes over a period of 3 hours. Results based on rise in both hydrogen and methane were classified separately as follows: 1) Negative study - no steady rise by >15ppm within first 90 minutes, 2) Definitive SBBO - initial rise at 15 minutes, with steady rise by >15ppm over baseline within 90 minutes, and no prior surgery 3) Indeterminate (pattern potentially consistent with SBBO) - all other cases. If concurrent scintigraphy was available, indeterminate studies were further classified into SBBO (rise prior to arrival of glucose load at the cecum) or rapid transit (rise after glucose load arrives at the cecum). Changes in classification based on the use of methane criteria in addition to hydrogen criteria were assessed. RESULTS: Results of classification via both hydrogen and methane criteria are shown in Table 1. 64% of all patients studied were methane producers (>3ppm), but only 9 patients showed a pattern of methane rise potentially consistent with SBBO (1 definitive SBBO, 8 indeterminate). Of the 4 indeterminate patients whom had concurrent scintigraphy, none were consistent with SBBO and 4 were consistent with rapid transit. Addition of methane criteria to hydrogen criteria identified 1 new case of SBBO, but in the absence of scintigraphy could potentially have identified 2 new false positive (rapid transit) cases. CONCLUSION: While methanogenic bacteria are prevalent, the pattern of methane production during glucose breath testing is more consistent with on-going colonic fermentation than SBBO in the vast majority of patients. Although methane breath testing rarely may detect cases of SBBO that would otherwise be undetected by hydrogen breath testing, it can also result in new false positive results in patients with rapid transit. Classification of studies via hydrogen and methane criteria
Su1427 Demographic and Clinical Factors Associated With Small Intestinal Bacterial Overgrowth (SIBO) Carolyn Newberry, Oleg Shulik, Ann Tierney, Octavia E. Pickett-Blakely BACKGROUND: Small Intestinal Bacterial Overgrowth (SIBO) is increasingly diagnosed in individuals presenting for evaluation of gastrointestinal symptoms. Although there are well recognized gastrointestinal conditions predisposing patients to SIBO, there is a paucity of literature examining other factors that may contribute to its development. In particular, studies evaluating the association between age, sex, and body mass index (BMI) and SIBO are few. Therefore, the aim of this study is investigate whether there is an association between demographic and clinical factors and the diagnosis of SIBO. METHODS: We conducted a retrospective, cross-sectional analysis of a large university-based population cohort utilizing our institutional electronic medical record. The study sample included all patients who underwent lactulose hydrogen breath testing (LHBT) between 6/1/2009 and 6/1/2013. Chart review was performed to obtain clinical data needed for the analysis. Patients were excluded from the analysis if data was missing. The primary outcome variable was LHBT result which was designated as negative, positive, or equivocal. The predictor variables were age, sex, and BMI. Multinomial logistic regression analysis was performed with models adjusted for proton pump inhibitor (PPI) use, history of gastroparesis, and history of gastrointestinal surgery. RESULTS: The study sample included 797 patients. Breath test results were negative, positive, or equivocal in 37%, 51%, and 12% respectively. Among the three LHBT groups, there was no significant difference in the mean age, sex (% female), or mean BMI. In the adjusted analysis there was an increased odds of having a positive LHBT compared with a negative LHBT in females as age increased [OR 0.90, 95% CI: 0.821- 0.987]. However, this finding was not observed in males [OR 0.974, 95% CI: 0.864- 1.098]. When examined alone, female sex was not associated with LHBT result. Although there was no statistically significant association observed between BMI and positive LHBT compared with a negative breath test, the result approached statistical significance [OR 0.976, CI: 0.951- 1.001]. CONCLUSIONS: This analysis shows that although there was not a significant association of sex and LHBT alone, there was an association between a positive LHBT result and increasing age in females but not males. Additionally, contrary to previous reports of increased frequency of SIBO in obese patients, in this study BMI was not statistically associated with a positive LHBT result, but closely approached clinical significance. Additional studies examining the association between demographic and clinical factors such as BMI and SIBO are needed to confirm these findings. However, clinicians should have a high index of suspicion to test for SIBO in older women as this subgroup may be at higher risk. Su1428 The Effect of Small Intestinal Bacterial Overgrowth on Lactose Intolerance Breath Test in Subjects With Non-Irritable Bowel Syndrome Tsachi Tsadok Perets, Dalal Hamouda, Einav Shporn, Yaron Niv, Ram Dickman Background: Irritable bowel syndrome (IBS) is a common chronic disorder of unclear origin characterized by abdominal pain, bloating and altered bowel features. In IBS patients with small intestinal bacterial overgrowth (SIBO), breath tests for lactose intolerance (LI) may be falsely abnormal. Aim: To assess the influence of SIBO on the results of breath tests to lactose in non-IBS subjects. Methods: A total of 348 non-IBS subjects with suspected LI underwent SIBO and LI testing by hydrogen breath test (HBT). We used 15 gr of lactulose dissolved in 50 ml of water, and 50 gr of lactose dissolved in 250 ml of water for the SIBO and LI-HBTs, respectively. The test result was considered positive when there was a rise above baseline in hydrogen concentration of 10 parts per million (ppm) for SIBO, and 20 ppm for LI. Results: Of the 348 subjects, 90 (26%) were negative for both SIBO and LI, 59 (17%) were positive for SIBO and negative for LI, 98 (28%) were negative for SIBO and positive for LI and 101 (29%) were positive for both SIBO and LI. Of those 101 SIBO and LI positive patients, 82 (81%) had an increase of hydrogen measurement above threshold between 30-90 minutes during their LI-HBT, implying SIBO. In contrast, subjects who were negative for SIBO and positive for LI showed an increase of hydrogen measurement above threshold between 120-180 minutes during their LI-HBT. Conclusions: Small intestinal bacterial overgrowth may affect the results of breath tests for LI in non-IBS subjects. We suggest that symptomatic patients with or without IBS should undergo SIBO testing and eradication if diagnosis was positive, prior to LI-HBT evaluation.
Su1426 Re-Evaluation of the Interpretation of the Lactulose Breath Test in the Diagnosis of Small Intestinal Bacterial Overgrowth - Guideline to Enhance Specificity Joseph Sunny, Cesar J. Garcia, Richard W. McCallum Introduction: Current guidelines for interpreting a positive lactulose breath test (LBT) in diagnosing small intestinal bacterial overgrowth (SIBO) rely on an initial peak value of hydrogen within 100 minutes of lactulose ingestion with a second peak before 180 minutes. Scintigraphic transit testing for lactulose by us and others indicates that mean cecal arrival time varied from 75 to 100 minutes and individual arrival times ranged from 30 to 139 minutes. Therefore, our goal was to propose new criteria for analysing the LBT for SIBO to overcome false positives which represent arrival of lactulose in the cecum. Methods: LBTs from our referral center were interpreted utilizing the following rules: 1) The Current Guidelines: a hydrogen concentration of greater than 20 parts per million (ppm) from a baseline less than 10 ppm achieved by 100 minutes after ingestion of 10 grams (g) of
AGA Abstracts
S-466