The Experts below are selected from a list of 10515 Experts worldwide ranked by ideXlab platform

Christopher C Thompson - One of the best experts on this subject based on the ideXlab platform.

  • impact of oral cecal transit time on the interpretation of lactulose Breath Tests after rygb a personalized approach to the diagnosis of sibo
    Obesity Surgery, 2019
    Co-Authors: Pichamol Jirapinyo, Tracy T Makuvire, William Dong, Walter W Chan, Christopher C Thompson
    Abstract:

    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.

  • impact of oral cecal transit time on the interpretation of lactulose Breath Tests after rygb a personalized approach to the diagnosis of sibo
    Obesity Surgery, 2019
    Co-Authors: Pichamol Jirapinyo, Tracy T Makuvire, William Dong, Walter W Chan, Christopher C Thompson
    Abstract:

    BACKGROUND 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. AIM 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. METHODS 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. RESULTS 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). CONCLUSION 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.

Barbara Braden - One of the best experts on this subject based on the ideXlab platform.

  • 13c methacetin and 13c galactose Breath Tests can assess restricted liver function even in early stages of primary biliary cirrhosis
    Scandinavian Journal of Gastroenterology, 2006
    Co-Authors: Julia Holtmeier, M Leuschner, A Schneider, U Leuschner, W F Caspary, Barbara Braden
    Abstract:

    Objective. The 13C-methacetin Breath test quantitatively evaluates cytochrome P450-dependent liver function. The 13C-galactose Breath test non-invasively measures the galactose oxidation capacity of the liver. The aim of this study was to find out whether these Breath Tests are sensitive parameters also in non-cirrhotic patients with primary biliary cirrhosis.Material and methods. Nineteen patients with early-stage primary biliary cirrhosis (no cirrhotic alterations in the liver biopsy, Ludwig stage I–III) and 20 healthy controls underwent the 13C-methacetin and 13C-galactose Breath Tests.Results. Patients with primary biliary cirrhosis metabolized less 13C-methacetin than controls (cumulative recovery within 30 min 7.5±2.4% versus 14.0±2.6%; p  9.8% was used for the cumulative recovery after 30 min, the methacetin Breath test reached 84.2% sensitivity and 95.0 specificity. In the 13C-galactose Breath test, the percentage recovery at 60 min in patients was 3.1±1.3%/h, and 6.3±1.1%/...

  • isotope selective non dispersive infrared spectrometry for detection of helicobacter pylori infection with 13c urea Breath test
    The Lancet, 1995
    Co-Authors: Sibylle Koletzko, Michael Haisch, Barbara Braden, I Seeboth, K Hengels, Berthold Koletzko, P Hering
    Abstract:

    Abstract 13 C-urea Breath Tests were sampled in 51 subjects with an isotope-selective non-dispersive infrared spectrometer (NDIRS) and compared with the results of conventional isotope-ratio mass-spectrometry (IRMS). Delta-over-baseline values of both methods correlated well ( r =0·976 at 15 min and 0·985 at 30 min, both p Helicobacter-pylori -negative and all 15 H-pylori- positive subjects. All infected subjects had values over 11 in all samples with both methods. NDIRS is of equal value as IRMS for the diagnosis of H pylori infection. Because NDIRS gives on-line results and is easier and cheaper, we consider NDIRS useful for clinical practice.

  • clinically feasible stable isotope technique at a reasonable price analysis of 13co2 12co2 abundance in Breath samples with a new isotope selective nondispersive infrared spectrometer
    Zeitschrift Fur Gastroenterologie, 1994
    Co-Authors: Barbara Braden, L P Duan, Michael Haisch, Wolfgang F Caspary, Bernhard Lembcke, Pavel Hering
    Abstract:

    : Up to now, stable isotope analysis of carbon dioxide in Breath samples is carried out with sensitive but very expensive and complex isotope ratio mass spectrometry (IRMS). Aiming at a more widespread application of Breath Tests in gastroenterological diagnostic routine, we tested a newly developed isotope selective non-dispersive infrared spectrometer (NDIRS) in comparison to IRMS. 13C-urea Breath Tests were performed in 63 patients as the routine screening method for Helicobacter pylori infection. Breath samples at baseline and (15) 30 min after administration of the test solution containing 13C-urea were analysed both by NDIRS and conventional IRMS. The correlation between the delta values of both devices was linear and in good agreement (r = 0.96; p < 0.0001; Y = 1.01 X -0.94). Comparing the delta over baseline-values, the correlation was Y = 1.11 X -0.36 (r = 0.98; p < 0.0001). Referring to the diagnosis of Helicobacter pylori infection with IRMS we calculated a sensitivity of 95.0% and an unchanged specificity (100%) for NDIR analysis. In conclusion, NDIRS appears a promising, easy to operate, and low cost potential alternative to conventional IRMS thus encouraging further detailed investigation and more widespread application of the noninvasive stable isotope technique in Breath Tests for gastrointestinal function testing.

Dan Ziegler - One of the best experts on this subject based on the ideXlab platform.

  • application of isotope selective nondispersive infrared spectrometry iris for evaluation of 13c octanoic acid gastric emptying Breath Tests comparison with isotope ratio mass spectrometry irms
    Clinical Chemistry, 1997
    Co-Authors: Peter Schadewaldt, Bernd Schommartz, Gregor Wienrich, Herbert Brosicke, Ralf Piolot, Dan Ziegler
    Abstract:

    Suitability of isotope-selective nondispersive infrared spectrometry (IRIS) for evaluation of [13C]octanoic acid gastric-emptying Breath test was assessed and compared with standard isotope ratio–mass spectrometry (IRMS). The estimated bias of IRMS and IRIS measurements of baseline-corrected 13CO2exhalation amounted to ± 0.1 and ± 0.6 Δδ values (n = 360), respectively. In Breath Tests performed on 60 diabetic patients, the gastric emptying parameters were calculated by nonlinear regression analysis of the time course of 13CO2exhalation: half-emptying time ( t 1/2,Breath, 90 ± 39 min), lag phase ( t lag,Breath, 34 ± 27 min), and gastric emptying coefficient (GEC, 2.9 ± 0.5). A reasonable linear correlation was found between the two methods ( y = IRIS, x = IRMS) with respect to Δδ values ( y = 0.35 + 0.92 x , r = 0.985, S y | x = ±0.6, n = 1116) and a rather good agreement of the computed gastric emptying parameters was obtained ( t 1/2,Breath: y = 0.99 x + 4.06, S y | x = ±6.3; t lag,Breath: y = 0.97 x + 0.96, S y | x = ±3.4; GEC: y = 0.97 x − 0.01, S y | x = ±0.09).

Albert Manninen - One of the best experts on this subject based on the ideXlab platform.

  • oxygen 18 and carbon 13 isotopes in eco 2 and erythrocytes carbonic anhydrase activity of finnish prediabetic population
    Journal of Breath Research, 2021
    Co-Authors: Anna Karlund, Teemu Kaariainen, Vili M Kostamo, Tarja Kokkola, Marjukka Kolehmainen, Timo A Lakka, Jussi Pihlajamaki, Albert Manninen
    Abstract:

    Complex human physiological processes create the stable isotopic composition of exhaled carbon dioxide (eCO2), measurable with noninvasive Breath Tests. Recently, isotope-selective Breath Tests utilizing natural fluctuation in 18O/16O isotope ratio in eCO2 have been proposed for screening prediabetic (PD) individuals. It has been suggested that 18O/16O fractionation patterns reflect shifts in the activity of carbonic anhydrase (CA), an enzyme involved in the metabolic changes in the PD state. To evaluate the applicability of the Breath sampling method in Finnish PD individuals, Breath delta values (BDVs, ‰) of 18O/16O (δ18O) were monitored for 120 min in real-time with a high-precision optical isotope ratio spectrometer, both in the fasting state and during a 2-hour oral glucose tolerance test (2h OGTT) with non-labelled glucose. In addition, the BDV of 13C/12C (δ13C) was measured, and total erythrocyte CA activity was determined. δ18O and CA did not demonstrate any statistically significant differences between PD and non-diabetic control (NDC) participants. Instead, δ13C was significantly lower in PD patients in comparison to NDCs in the fasting state and at time points 90 and 120 min of the 2h OGTT, thus indicating slightly better potential in identifying Finnish PD individuals. However, overlapping values were measured in PD participants and NDCs, and therefore, δ13C cannot be applied as a sole measure in screening prediabetes at an individual level. Thus, because the combination of environmental and lifestyle factors and anthropometric parameters has a greater effect on glucose metabolism and CA activity in comparison to the PD state, 18O/16O and 13C/12C fractionations or CA activity did not prove to be reliable biomarkers for impaired glucose tolerance in Finnish subjects. This study was conducted under the clinicaltrials.gov ID NCT03156478.

L D Faller - One of the best experts on this subject based on the ideXlab platform.

  • feasibility of analysing 13c urea Breath Tests for helicobacter pylori by gas chromatography mass spectrometry in the selected ion monitoring mode
    Alimentary Pharmacology & Therapeutics, 1996
    Co-Authors: V N Kasho, S Cheng, Dennis M Jensen, H Ajie, W N P Lee, L D Faller
    Abstract:

    Background: The [13C]urea Breath test for Helicobacter pylori is nonradioactive, as well as noninvasive, but few clinical laboratories have the expensive isotope ratio mass spectrometer used for analysis. Methods: To demonstrate the feasibility of analysing [13C]urea Breath Tests with a gas chromatograph-mass spectrometer routinely used for drug testing, 13CO2 standards for Breath Tests and Breath samples from patients in a multiple-blind study were analysed. The Breath samples were also analysed by isotope ratio mass spectrometry, and the diagnoses were compared with biopsy results. Results: The precision of the enrichment measurements by gas chromatography–mass spectrometry was 1.1 parts per thousand, and the calculated differences in enrichment between standard gases equaled the certified values. The sensitivity (94%), specificity (94%), and percentage agreement (94%) for diagnosis of Helicobacter pylori (n=34) were as high or higher than for analysis of replicate Breath samples by isotope ratio mass spectrometry and comparable to the values reported for diagnosis of the bacterium by other currently accepted Tests. Conclusions: The study demonstrates that a gas chromatograph–mass spectrometer can be used to analyse [13C]urea Breath Tests, thus potentially lowering the cost of the test and increasing the number of laboratories that can perform the test.