Showing papers on "Breath test published in 2005"
TL;DR: The lactulose breath test is a reliable and non‐invasive test for the diagnosis of small intestinal bacterial overgrowth and sugar malabsorption and may play a role in irritable bowel syndrome.
Abstract: Background Small intestinal bacterial overgrowth and sugar malabsorption (lactose, fructose, sorbitol) may play a role in irritable bowel syndrome. The lactulose breath test is a reliable and non-invasive test for the diagnosis of small intestinal bacterial overgrowth. The lactose, fructose and sorbitol hydrogen breath tests are widely used to detect specific sugar malabsorption. Aim To assess the extent to which small intestinal bacterial overgrowth may influence the results of hydrogen sugar breath tests in irritable bowel syndrome patients. Methods We enrolled 98 consecutive irritable bowel syndrome patients. All subjects underwent hydrogen lactulose, lactose, fructose and sorbitol hydrogen breath tests. Small intestinal bacterial overgrowth patients were treated with 1-week course of antibiotics. All tests were repeated 1 month after the end of therapy. Results A positive lactulose breath test was found in 64 of 98 (65%) subjects; these small intestinal bacterial overgrowth patients showed a significantly higher prevalence of positivity to the lactose breath test (P Conclusions In irritable bowel syndrome patients with small intestinal bacterial overgrowth, sugar breath tests may be falsely abnormal. Eradication of small intestinal bacterial overgrowth normalizes sugar breath tests in the majority of patients. Testing for small intestinal bacterial overgrowth should be performed before other sugar breath tests tests to avoid sugar malabsorption misdiagnosis.
189 citations
TL;DR: No data exist on small intestinal bacterial overgrowth prevalence in a significant population of healthy non‐irritable bowel syndrome subjects, and differences in criteria to define irritable bowel Syndrome patients and methods to assess small intestinal bacteria overgrowth may explain different results.
Abstract: Summary
Background: Studies assessing the prevalence of small intestinal bacterial overgrowth in irritable bowel syndrome gave contrasting results. Differences in criteria to define irritable bowel syndrome patients and methods to assess small intestinal bacterial overgrowth may explain different results. Moreover, no data exist on small intestinal bacterial overgrowth prevalence in a significant population of healthy non-irritable bowel syndrome subjects.
Aim: To assess the prevalence of small intestinal bacterial overgrowth by glucose breath test in patients with irritable bowel syndrome symptoms with respect to a consistent control group.
Methods: Consecutive patients with irritable bowel syndrome according to Rome II criteria were enrolled. The control population consisted of 102 sex- and age-matched healthy subjects without irritable bowel syndrome symptoms. All subjects underwent glucose breath test. A peak of H2 values >10 p.p.m above the basal value after 50 g of glucose ingestion was considered suggestive of small intestinal bacterial overgrowth.
Results: A total of 65 irritable bowel syndrome patients and 102 healthy controls were enrolled. Positivity to glucose breath test was found in 31% of irritable bowel syndrome patients with respect to 4% in the control group, the difference between groups resulting statistically significant (OR: 2.65; 95% CI: 3.5–33.7, P < 0.00001).
Conclusions: The present case–control study showed an epidemiological association between irritable bowel syndrome and small intestinal bacterial overgrowth. Placebo-controlled small intestinal bacterial overgrowth-eradication studies are necessary to clarify the real impact of small intestinal bacterial overgrowth on irritable bowel syndrome symptoms.
178 citations
TL;DR: The lactulose breath test did not reliably detect a common association between bacterial overgrowth and IBS in the patient population of Rome II positive IBS patients and compared it to the 14C-d-xylose Breath test, a test with acknowledged greater specificity for bacterial over growth.
163 citations
TL;DR: In a setting where desensitisation played no role, erythromycin enhanced gastric emptying was not associated with a beneficial effect on meal related symptom severity.
Abstract: Background and aims: Although delayed gastric emptying is considered a major pathophysiological mechanism in functional dyspepsia, the efficacy of prokinetic drugs has not been established. Recent studies using macrolide prokinetics were negative but receptor desensitisation may have played a role. The aim of the present study was to evaluate the influence on meal induced symptoms of acutely administered erythromycin in patients with gastroparesis.
Methods: In 20 patients with functional dyspepsia, gastric emptying was studied twice using the 14C octanoic acid and 13C glycin breath test to establish the reproducibility of the test. Breath samples were taken before the meal and at 15 minute intervals for a period of 240 minutes postprandially. At each breath sampling, the patient was asked to grade the intensity (0–3) of six dyspeptic symptoms. Twenty four patients (three men, mean age 43.5 (3) years) with dyspeptic symptoms and delayed gastric emptying were studied twice after pretreatment with saline or erythromycin intravenously.
Results: Meal related symptom severity scores were reproducible. Treatment with erythromycin significantly enhanced solid and liquid gastric emptying (t1/2 146 (27) v 72 (7) minutes, respectively (p<0.01), and 87 (6) v 63 (5) minutes (p<0.001)). Only the severity of bloating was significantly improved by erythromycin (23 (3.9) v 14.5 (2.7); p<0.01); all other symptoms and the cumulative meal related symptom score were not altered by erythromycin.
Conclusions: In a setting where desensitisation played no role, erythromycin enhanced gastric emptying was not associated with a beneficial effect on meal related symptom severity.
146 citations
TL;DR: It is postulated that cranberry juice would be effective in the suppression of H. pylori in an endemically infected population at high risk for gastric cancer.
Abstract: Background. Helicobacter pylori infection is a major cause of peptic ulcer disease and gastric cancer. This study postulated that cranberry juice would be effective in the suppression of H. pylori in an endemically infected population at high risk for gastric cancer.
Materials and methods. A prospective, randomized, double-blind, placebo-controlled trial was conducted in Linqu County of Shandong Province, China, where 189 adults aged 48.9 ± 11.2 years (mean ± SD) with H. pylori infection were randomly divided into two groups: cranberry juice (n = 97) and placebo (n = 92). Participants were assigned to orally receive two 250-ml juice boxes of cranberry juice or matching placebo beverage daily for 90 days. The degree of H. pylori infection was determined using the 13C-urea breath test before randomization at 35 and 90 days of intervention to assess the efficacy of cranberry juice in alleviating infection.
Results. A total of 189 subjects with positive 13C-urea breath test results prior to randomization completed the study. At day 35 of intervention, 14 of the 97 (14.43%) from the the cranberry juice treatment group and 5 of the 92 (5.44%) of the placebo recipients had negative 13C-urea breath test results. After 90 days, the study concluded that 14 of the 97 subjects in the cranberry juice treatment group versus 5 of the 92 in the placebo group yielded negative test results. Eleven individuals from the cranberry juice treatment group and only two from the placebo group were negative at 35 and 90 days of experiment. These results are significant (p < .05).
Conclusions. Regular consumption of cranberry juice can suppress H. pylori infection in endemically afflicted populations.
127 citations
TL;DR: The OBT detects a significant delay in gastric emptying of a solid test meal in patients with Parkinson's disease and is associated with disease severity.
116 citations
TL;DR: A small number of controlled studies assessing choice and duration of antibiotic therapy for small intestinal bacterial overgrowth are available and these studies suggest that using antibiotics for this purpose is a viable treatment option.
Abstract: SUMMARY Background: Few controlled studies assessing choice and duration of antibiotic therapy for small intestinal bacterial overgrowth are available. Aim: To assess efficacy, safety and tolerability of different doses of rifaximin, a broad spectrum non-absorbable antibiotic, for intestinal bacterial overgrowth eradication. Methods: We enrolled 90 consecutive patients affected by small intestinal bacterial overgrowth. The presence of small intestinal bacterial overgrowth was based on the occurrence of a rise of H2 values >12 p.p.m. above the basal value after 50 g glucose ingestion. Patients were randomized in three 7-day treatment groups: rifaximin 600 mg/day (group 1); rifaximin 800 mg/day (group 2) and rifaximin 1200 mg/day (group 3). Glucose breath test was reassessed 1 month after the end of therapy. Compliance to the treatment and incidence of side-effects were also evaluated. Results: No drop-outs were observed in the three groups. Glucose breath test normalization rate was significantly higher in group 3 (60%) with respect to group 1 (17%; P < 0.001) and group 2 (27%, P < 0.01). No significant differences in patient compliance and incidence of side-effects were found among groups. Conclusions: Higher doses of rifaximin lead to a significant gain in terms of therapeutic efficacy in small intestinal bacterial overgrowth eradication without increasing the incidence of side-effects.
112 citations
TL;DR: The electronic nose is a new biosensor technology that correlates with a clinical pneumonia score that is good correlation with the actual pneumonia score.
Abstract: Background:The authors performed a prospective study to determine whether breath test analysis using an electronic nose correlates with a clinical pneumonia score.Methods:Exhaled gas was sampled from the expiratory limb of the ventilator in mechanically ventilated surgical intensive care patients an
108 citations
TL;DR: Analysis of the −13910 T/C variant can be considered a good test for predicting the presence of lactase non-persistence in a patient population with suspected lactose malabsorption.
Abstract: Background and aims Recent publications have found that the CC genotype of the DNA variant -13910 T/C upstream of the LCT gene is associated with lactase non-persistence. We therefore compared the value of DNA testing for this variant (DNA test) with the lactose hydrogen breath test (H 2 test), which is the clinical standard for the diagnosis of lactase non-persistence. Patients and methods One hundred and twenty-three consecutive patients with suspected lactose malabsorption were tested for the presence of the -13910 T/C variant by polymerase chain reaction-restriction fragment length polymorphism analysis. These patients also underwent the H 2 test after ingestion of 50 g lactose. Results Thirty-seven subjects had a CC genotype of the -13910 T>C polymorphism suggesting lactase non-persistence; 36 (97%) had also a positive H 2 test Eighty-six subjects had either a TC or a TT genotype suggestive of lactase persistence. Seventy-four (86%) of these tested negative on the H 2 test, while 12 patients had a positive H 2 test. In eight of these 12 patients duodenal biopsies showed no evidence of small bowel disease. One patient carrying a CC genotype had a negative H 2 test. In this patient the rise in serum glucose after oral lactose was normal, furthermore H 2 non-excretion was also excluded. Conclusions An excellent correlation is observed between a CC genotype and a positive H 2 test, whereas the correlation between a TC or TT genotype and a negative H 2 test result is less strong. Analysis of the -13910 T/C variant can be considered a good test for predicting the presence of lactase non-persistence in a patient population with suspected lactose malabsorption.
98 citations
TL;DR: The 13C‐methacetin breath test enables the quantitative evaluation of the cytochrome P450‐dependent liver function and can be used as a standalone test for liver function evaluation.
Abstract: BACKGROUND The 13C-methacetin breath test enables the quantitative evaluation of the cytochrome P450-dependent liver function. AIM To find out whether this breath test is sensitive in noncirrhotic patients also with chronic hepatitis C in early stages of fibrosis. METHODS Sixty-one healthy controls and 81 patients with chronic hepatitis C underwent a 13C-methacetin breath test. In all patients, a liver biopsy was performed. The liver histology was classified according to the histology activity index-Knodell score. RESULTS Delta over baseline values of the patients at 15 min significantly differed from controls (19.2 +/- 9.2 per thousand vs. 24.1 +/- 5.7 per thousand; P < 0.003). The cumulative recovery after 30 min in patients was 11.4 +/- 4.8% and in healthy controls 13.8 +/- 2.8% (P < 0.002). However, patients with early fibrosis (histology activity index IVB) did not differ in delta over baseline values of the patients at 15 min (23.2 +/- 7.9 per thousand vs. 22.6 +/- 7.2 per thousand; P = 0.61) or cumulative recovery (13.6 +/- 3.7% vs. 13.2 +/- 3.8%; P = 0.45) from patients with more advanced fibrosis (histology activity index IVC). Patients with clinically nonsymptomatic cirrhosis (histology activity index IVD; Child A) metabolized 13C-methacetin to a significantly lesser extent (delta over baseline values of the patients at 15 min: 8.3 +/- 4.9 per thousand; P < 0.005 and cumulative recovery after 30 min: 5.6 +/- 3.2%; P < 0.003). The 13C-methacetin breath test identified cirrhotic patients with 95.0% sensitivity and 96.7% specificity. CONCLUSION The non-invasive 13C-methacetin breath test reliably distinguishes between early cirrhotic (Child A) and noncirrhotic patients, but fails to detect early stages of fibrosis in patients with chronic hepatitis C.
92 citations
TL;DR: Prevalence of celiac disease seems to be high among patients affected by CD, and this finding should be kept in mind at the time of the first diagnosis of CD; a gluten‐free diet should be promptly started.
Abstract: Background: Recent literature has shown a correlation between Crohn's disease (CD) and celiac disease, but a prospective study has not been performed. Our aim was to evaluate the prevalence of celiac disease in a consecutive series of patients affected by CD, in whom the disease was diagnosed for the first time.
Methods: From January to December 2004, we diagnosed 27 patients affected by CD (13 men and 14 women; mean age, 32.3 yrs; range, 16-69 yrs). In all patients, we performed antigliadin, antiendomysium, and antitransglutaminase antibody tests, and the sorbitol H2 breath test evaluation. In case of antibodies and/or sorbitol positivity, esophagogastroduodenoscopy was performed for a small bowel biopsy.
Results: Antigliadin, antiendomysium, and antitransglutaminase antibody tests were positive in 8/27 (29.63%), 4/27 (14.81%), and 5/27 (18.52%) patients, respectively, whereas the sorbitol H2 breath test was positive in 11/27 (40.74%) patients: all of them underwent esophagogastroduodenoscopy. Nine of 11 patients showed signs of duodenal endoscopic damage, and 5/9 (55.55%) showed histologic features of celiac disease (18.52% of overall CD population studied): 2 showed Marsh IIIc lesions (1 patient affected by ileal CD and 1 affected by ileo-colonic CD), 2 showed Marsh IIIb lesions (all of them affected by ileo-colonic CD), 1 showed a Marsh IIIa lesion (1 patient affected by colonic CD).
Conclusions: Prevalence of celiac disease seems to be high among patients affected by CD, and this finding should be kept in mind at the time of the first diagnosis of CD; a gluten-free diet should be promptly started.
TL;DR: Adolescents with functional dyspepsia demonstrate increased postprandial symptoms after challenge, delayed gastric emptying, and a reduced gastric volume response to feeding.
TL;DR: The recommendations of the German Society of Neurogastroenterology and Motility and of theGerman Society of Digestive and Metabolic Diseases for clinically relevant H 2 - and 1 3 C-breath tests for gastroenterological diseases are presented.
Abstract: H (2)- and (13)C-breath tests are valuable non-invasive diagnostic tools for gastroenterological diseases. H (2)-breath tests are clinically established for the diagnosis of carbohydrate intolerance resulting from malabsorption (H (2)-breath tests with lactose, fructose, saccharose, sorbitol), of bacterial overgrowth (glucose H (2)-breath test) and for measurement of orcoceal transit time (lactulose H (2)-breath test). The (13)C-urea breath test is regarded as the "gold standard" procedure for the diagnosis of Helicobacter pylori infection. Moreover, (13)C-breath tests for measurement of gastric emptying can be considered as clinically established, meanwhile. (13)C-breath tests for the evaluation of pancreatic exocrine function or liver function can also be used clinically; however, they currently offer no substantial advantage over other diagnostic procedures. A major disadvantage of all breath tests is that they lack standardization although modifications of the test meal or solution, of the test performance and of the evaluation of data may markedly influence the results. Thus, this article presents the recommendations of the German Society of Neurogastroenterology and Motility and of the German Society of Digestive and Metabolic Diseases for clinically relevant H (2)- and (13)C-breath tests. Indications for the examinations, the procedures to be followed, the analysis of the obtained data and the conclusions to be drawn are delineated. The literature on which the recommendations are based is reviewed. However, personal experience of the authors is also taken into account since numerous questions regarding optimal test performance are not clarified by adequate studies.
TL;DR: Treatment failure in Helicobacter pylori treatment failure is a growing problem in daily practice and needs to be considered in clinical practice.
Abstract: Summary
Background: Helicobacter pylori treatment failure is a growing problem in daily practice.
Aim: To determine the efficacy of the combination of rabeprazole, levofloxacin and furazolidone as a rescue therapy.
Methods: Duodenal ulcer patients previously submitted, without success, to at least two H. pylori treatment regimens were included. Gastroscopy (urease test, histological examination and culture) and 13C-urea breath test were performed. All patients received a combination of rabeprazole 20 mg, levofloxacin 500 mg and furazolidone 200 mg (two tablets) administered in a single dose in the morning for 10 days. Clinical examination and a new 13C-urea breath test were performed 90 days after therapy.
Results: Twelve patients (eight females and four males), mean age 43 (30–58) years were included. Two patients failed to complete the treatment because of nausea and vomiting. Ten patients completed the study and took all the medications as advised. Culture was obtained in six patients: 100 and 83% of the samples were sensitive to furazolidone and levofloxacin, respectively. Per-protocol and intention-to-treat eradication rates were 100 and 83% (P = 0.019).
Conclusions: the combination of rabeprazole, levofloxacin and furazolidone in a single daily dose for 10 days constitutes a highly-effective and low-cost alternative as a third-line therapy in patients infected with H. pylori.
Journal Article•
TL;DR: An overview of the current knowledge on the 13C-octanoic acid breath test is given with special emphasis on the principle of the test, the mathematics used to analyse the results, and the physiological, pathological, and pharmacological aspects of gastric emptying studied with this new method.
Abstract: Non invasive evaluation of gastric emptying is generally performed by scintigraphy which is, however, difficult to perform and not suitable to children and childbearing women. A new method based on stable isotope breath testing analysis has been introduced in clinical practice: the 13C-octanoic acid breath test. In this paper, an overview of the current knowledge on this technique is given with special emphasis on the principle of the test, the mathematics used to analyse the results, and the physiological, pathological, and pharmacological aspects of gastric emptying studied with this new method.
TL;DR: Evidence of deranged intestinal motility in nondiabetic patients with NAFLD is shown and support the hypothesis that NA FLD could be linked to endotoxin-induced liver damage of intestinal origin.
Abstract: Intestinal bacterial overgrowth (IBO) has been suggested to play a pathogenic role in patients with nonalcoholic fatty liver disease (NAFLD). Delayed intestinal transit may contribute to IBO development. Ten nondiabetic patients with NAFLD and abnormal liver enzymes were recruited. Ten healthy individuals, matched by sex, age, and body mass index, were used as controls. Orocecal transit time (OCTT) was measured by the lactulose breath test. Anti-endotoxin core antibodies (EndoCAb) were determined. The effect of oral norfloxacin (400 mg BID during 2 weeks) on liver enzymes, lactulose breath test, and EndoCAb was also studied. NAFLD patients had higher basal breathed H2 and prolonged OCTT compared to controls (127 ± 61 vs. 57 ± 23 min, respectively; P = 0.0037). EndoCAb titers were similar in NAFLD patients and controls. Norfloxacin administration had no effect on ALT levels, lactulose breath test, or EndoCAb titers in patients with NAFLD. The present data show evidence of deranged intestinal motility in nondiabetic patients with NAFLD and support the hypothesis that NAFLD could be linked to endotoxin-induced liver damage of intestinal origin.
TL;DR: Combination of the tests increased the diagnostic accuracy of either test alone and reached 92.5% specificity and 100% sensitivity for the diagnosis of cirrhosis in patients with chronic liver disease.
TL;DR: The 13C-urea breath test has been validated in children of different age groups in a significant number of infected and noninfected children in several countries and, thus far, is the only noninvasive test that fulfills sensitivity and specificity quality standards.
Abstract: Noninvasive tests can be used for the initial diagnosis of Helicobacter pylori infection and to monitor the success of eradication therapy. In populations with a low prevalence of H pylori infection (children living in North America and Europe), a high sensitivity is required to make the test valuable for clinical practice. The 13C-urea breath test has been validated in children of different age groups in a significant number of infected and noninfected children in several countries and, thus far, is the only noninvasive test that fulfills sensitivity and specificity quality standards. In studies to date, enzyme immunoassays using monoclonal antibodies to detect H pylori antigen in stool provide excellent results, but the number of children tested, particularly post-treatment, is not sufficient to recommend the test. All other noninvasive stool tests or methods based on the detection of specific antibodies in serum, whole blood, urine or saliva have limited accuracy in comparison with the 13C-urea breath test. Therefore, these tests cannot be recommended for clinical decision making in pediatric patients.
TL;DR: The purpose of the present study was to evaluate the diagnostic accuracy of the 13C‐UBT according to age, and to determine the optimal cut‐off value in children.
Abstract: Background and aims The (13)C-urea breath test ((13)C-UBT) is a reliable non-invasive method of diagnosing Helicobacter pylori infection in adults and children. However, only a few validation studies have been performed on the (13)C-UBT in very young children. The purpose of the present study was to evaluate the diagnostic accuracy of the (13)C-UBT according to age, and to determine the optimal cut-off value in children. Methods A total of 307 (13)C-UBT were performed in 274 children. All were compared with the results of endoscopic biopsy-based methods to confirm H. pylori infection. Seventy-five milligrams of (13)C-urea was ingested without a test meal. Two breath samples were collected at 0 and 30 min. The optimal cut-off value of the (13)C-UBT was assessed by determining the sensitivity, specificity, false negative, and false positive results, at cut-off values ranging from 2.0 to 10.0 per thousand. Results The delta over baseline (DOB) values of the (13)C-UBT showed a significant negative correlation with age in both the H. pylori-positive group (r = -0.309; P = 0.005) and the H. pylori-negative group (r = -0.162; P = 0.015). High false positive results and low specificity were noted in children aged 6 years or less compared with children older than 6 years at a cut-off value of 4.0 per thousand (false positives; 8.3%vs 0.85%, specificity; 89.8%vs 98.8%). After adjusting the cut-off value, the optimal cut-off values were found to be 4.0 per thousand in children older than 6 years and 7.0 per thousand in children aged 6 years or less. Conclusions The cut-off value of the (13)C-UBT recommended regardless of age must be adjusted in preschool children to reduce the false positive results.
TL;DR: This non-invasive test can be used to monitor drug-related mitochondrial toxicity in vivo and to discover early and asymptomatic damage of the respiratory chain in HIV-1-infected patients receiving antiretroviral therapy.
Abstract: Objectives: A major side effect of antiretroviral drugs is nucleoside reverse transcriptase inhibitor (NRTI)-related mitochondrial toxicity, the in vivo diagnosis of which is difficult and not yet standardized. We used the [ 13 C]methionine breath test to investigate hepatic mitochondrial oxidation in HIV-1-infected patients receiving antiretroviral therapy. Patients and methods: The [ 13 C]methionine breath test was performed in healthy subjects (n = 10), HIV-infected patients on antiretroviral therapy with (n = 6) and without (n = 15) hyperlactataemia and naive HIV-infected patients (n = 11). After oral administration of [ 13 C]methionine (2 mg/kg body weight), hepatic methionine metabolism was measured by breath 13 CO 2 enrichment, expressed as δ over baseline (DOB) every 15 min for 120 min by mass spectrometry. Results: The four study groups showed a significant difference in 13 CO 2 exhalation (P = 0.001). HIV-infected patients on antiretroviral therapy with normal serum lactate had reduced exhalation of 13 CO 2 compared with healthy subjects (DOB mean peak: 8.82 ± 0.62 versus 11 ± 0.9, P<0.05). HIV patients with hyperlactataemia had even lower values when compared with patients with normal lactataemia (DOB mean peak: 4.98 ± 0.68 versus 8.82 ± 0.62, P < 0.05). Conclusions: The [ 13 C]methionine breath test possibly showed mitochondrial impairment in antiretroviral-treated HIV-positive patients, particularly with hyperlactataemia. This non-invasive test can be used to monitor drug-related mitochondrial toxicity in vivo and to discover early and asymptomatic damage of the respiratory chain.
TL;DR: The aim is to evaluate the correlation between 13C‐UBT values and H. pylori bacterial load.
Abstract: Background. Some authors have reported, using different protocols, that 13C-urea breath test (13C-UBT) is capable of assessing the intragastric Helicobacter pylori bacterial load, whereas others have not confirmed these data. Our aim is to evaluate the correlation between 13C-UBT values and H. pylori bacterial load.
Materials and Methods. One hundred ninety-two patients diagnosed H. pylori-positive by rapid urease test, histology, and 13C-UBT were enrolled. H. pylori bacterial load (H. pylori score) and gastritis activity (activity score) were evaluated according to the Updated Sydney System. 13C-UBT was performed according to the European Standard Protocol. Breath samples were obtained every 10 minutes for 60 minutes in 52 patients and at 30 minutes (T30) in 140 patients and analyzed by mass spectrometry.
Results. At T30, mean ± SD excess delta 13CO2 excretion was 17.4 ± 1.1, 29.9 ± 2.2, and 48.7 ± 4.8 in patients with H. pylori scores 1, 2, and 3, respectively. This difference was statistically significant: H. pylori score 1 versus 2, p < .005; score 1 versus 3, p < .05; score 2 versus 3, p < .05. A significant positive correlation (G = 0.59) was found between H. pylori score and activity score of chronic gastritis. At T40 and T50 significant correlation between mean excess delta 13CO2 excretion and bacterial load was achieved only in patients with H. pylori scores 1 and 3.
Conclusions. 13C-UBT European Standard Protocol values correlate with H. pylori bacterial load and the activity of gastritis at T30 breath sampling time.
TL;DR: The urea breath test is the more accurate and detects products of the enzyme urease produced by live H pylori in the stomach and is 95% sensitive and specific.
Abstract: Urea breath test and stool antigen test are better than serological tests
M anaging dyspepsia costs the NHS over £500m annually.1 European dyspepsia guidelines and those from the National Institute for Clinical Excellence (NICE) say that patients with persistent or recurrent uncomplicated dyspepsia should have a non-invasive Helicobacter pylori test and, if the test is positive, receive triple therapy.2–4 With a policy requiring non-invasive testing and treatment we need to use an accurate test so that the patients receive the correct treatment. The urea breath test and serology were the first non-invasive tests available; the urea breath test is the more accurate. This test detects products of the enzyme urease produced by live H pylori in the stomach and is 95% sensitive and specific.5 The breath test has not been used much in primary care in the United Kingdom, probably because it is time consuming as it requires two breath samples, taken 20 minutes apart.
Serology is the …
TL;DR: Though hepatic mitochondrial function might be impaired in patients with NASH, total octanoic acid remains normal and gender-specific metabolic modifications seem to account for significant differences of the cumulative 13CO2 recovery in women and men.
Abstract: OBJECTIVES Among numerous factors which account for the pathogenesis of non-alcoholic steatohepatitis (NASH), hepatic mitochondrial beta-oxidation is considered to play a pivotal role. We performed a (13)C-based breath test with a medium-chain fatty acid to non-invasively assess total body beta-oxidation in patients with NASH and in healthy controls. METHODS We performed a simplified (13)CO(2)-based breath test in 16 patients with histologically proven NASH and 24 healthy controls. One hundred milligrams of sodium (13)C-octanoate dissolved in 200 ml of water were orally administered and breath samples were collected before and during 3 h following administration. The samples were analysed for the cumulative (13)CO(2) recovery (%-cum-dose) by non-dispersive infrared spectrometry. Additionally, data of 69 patients who had undergone a C-octanoate breath test for the assessment of gastric emptying were retrospectively evaluated for the %-cum-dose. RESULTS The cumulative (13)CO(2) recovery 3 h after the administration of the substrate did not differ among patients with NASH and controls (34.6 +/- 7.0% vs. 34.6 +/- 6.5%, P = 0.90). Compared with men, women yielded a significantly higher cumulative (13)CO(2) excretion in both controls (30.1 +/- 5.7% vs. 38.5 +/- 4.4%, P = 0.0008) and NASH patients (30.2 +/- 5.4% vs. 39.0 +/- 6.5%, P = 0.031). Forty-two of 69 patients (61%) of the gastric emptying group showed a normal gastric emptying rate. Among these patients, women also demonstrated a tendency for a higher (13)CO(2) recovery compared with men (P = 0.055). This was not the case in 27 patients with delayed gastric emptying (P = 0.47). CONCLUSIONS Though hepatic mitochondrial function might be impaired in patients with NASH, total beta-oxidation of octanoic acid remains normal. Gender-specific metabolic modifications seem to account for significant differences of the cumulative (13)CO(2) recovery in women and men. This may have further consequences for the appraisal of (13)C breath tests which involve octanoic acid. Further trials focusing on the assessment of body composition and energy expenditure could contribute essential further information.
TL;DR: In horses, in contrast to most species, dietary fat supplementation may not have a profound effect on gastric motility.
Abstract: Objective—To evaluate the effect of ingestion of a high-carbohydrate versus a high-fat meal on relaxation of the proximal portion of the stomach and subsequent gastric emptying in horses. Animals—6 healthy adult horses. Procedure—The study consisted of 2 phases. In phase I, horses were offered a high-fat (8% fat) or a high-carbohydrate (3% fat) pelleted meal (0.5 g/kg) of identical volume, caloric density, and protein content. In phase II, meals consisted of a commercial sweet feed meal (0.5 g/kg) or this meal supplemented with corn oil (12.3% fat) or an isocaloric amount of glucose (2.9% fat). Proximal gastric tone was measured by variations in volume of an intragastric bag introduced through a gastric cannula and maintained with a constant internal pressure by an electronic barostat. Rate of gastric emptying was measured simultaneously with the 13C-octanoic acid breath test. Interaction between both techniques was studied in additional experiments. Results—Meals with higher carbohydrate content induced ...
TL;DR: The breath test for OMVOCs could potentially provide an objective new test for the assessment of oral malodor, and may account for the increased risk of atherosclerosis, coronary heart disease and stroke associated with periodontal disease.
Abstract: Background: We performed a pilot study of a new method to identify the volatile organic compounds (VOCs) in breath associated with oral malodor, using gas chromatography and mass spectroscopy (GC/MS).
Methods: Oral cavity breath was collected from seven patients with oral malodor. Breath samples (150 ml) were concentrated onto sorbent traps and analyzed by GC/MS.
Results: Organoleptic scores ranged from 3.0 to 4.0 (mean = 3.3) on a scale of 0–5. Twenty-four of 30 (80.0%) of the most abundant oral malodor volatile organic compounds (OMVOCs) were alkanes and methylated alkanes. These VOCs are products of oxidative stress, generated by lipid peroxidation of polyunsaturated fatty acids in cell membranes.
Conclusions: Increased oxidative stress in the oral cavity of patients with oral malodor may account for the increased risk of atherosclerosis, coronary heart disease and stroke associated with periodontal disease. The breath test for OMVOCs could potentially provide an objective new test for the assessment of oral malodor.
TL;DR: MeBT is a simple noninvasive method to detect mitochondrial dysfunction in HIV-infected patients that correlates with mtDNA depletion in PBMCs of ART-treated individuals and may reflect the functional relevance of viral-mediated mitochondrial toxicity.
Abstract: Objective:To assess mitochondrial respiratory chain dysfunction in different treatment groups of HIV-infected patients with normal serum lactate by measuring hepatic mitochondrial decarboxylation capacity by the 13C-methionine breath test (MeBT) and to correlate MeBT results with mitochondrial DNA (
TL;DR: The 13C-ABT method is supported as a reliable and reproducible method to evaluate gastric emptying of liquids in healthy infants and in infants with gastroesophageal reflux in the field of research and in clinical evaluations.
TL;DR: It has long been believed that the relevance of OBT is based on the assumption that GE is the rate-limiting step for CO2 exhalation, but this is thought to be incorrect and the variation in CO2 excretion pattern mainly originates from the variations in GE rather than the postgastric events.
Abstract: To logically reply to these questions, precise kinetics of 13C in the human body should be recalled (Figure 1) (5). 13C-Octanoate is rapidly absorbed once it is emptied from the stomach. Then 13C-octanoate reaches the liver, where it undergoes preferential oxidation to CO2. Subsequently, CO2 appears in the systemic circulation, enters the pulmonary artery, and is exhaled quickly by the lung. As the rate of CO2 exhalation is regulated according to first-order kinetics (6), a certain portion of the CO2 survives the pulmonary elimination, and the survivor circulates throughout the body. Circulating CO2 distributes into the fast and slowly exchanging CO2 pools and is eliminated via the respiratory and nonrespiratory routes. The distribution and the elimination occur simultaneously. Note that the rate at which CO2 appears in the systemic circulation is the surrogate measure of gastric emptying rate in OBT (Figure 1). 1. It has long been believed that the relevance of OBT is based on the assumption that GE is the rate-limiting step for CO2 exhalation (1). However, we think this is incorrect. For the assumption to be correct, the postgastric processes should be much more rapid than GE; in other words, there should be no barriers to the intestinal absorption, the hepatic oxidation, and the pulmonary elimination (7). Previous works elucidated that 13C is transferred from the small gut to the systemic circulation so quickly that the barriers to the absorption and oxidation could effectively be overlooked (1, 8). On the other hand, no studies on OBT have clearly stated whether or not the barrier to elimination exists. Physiologic experiments showed that, both after intraduodenal administration of 13C-octanoate and after an intravenous bolus injection of 13C-sodium bicarbonate, the time-vs.-pulmonary CO2 excretion rate curve exhibits an exponentially decreasing elimination phase, characterized by a half-life of about 60 min (7, 9). Because the route of 13C administration little modifies the CO2 elimination kinetics (10), it is reasonable to consider that it takes 60 min for CO2 to be eliminated by half. The half-elimination time of 60 min is substantially long, indicating the presence of the barrier to the elimination. If GE is more rapid than the elimination (the half-GE time is shorter than 60 min), the elimination step limits the pulmonary CO2 excretion. Supposing the situation is converse, GE is, in turn, the rate-limiting step for CO2 excretion. This phenomenon is a common sense in pharmacokinetics (11). The postgastric processing is more uniform than GE within and between individuals (1, 8, 12). This just warrants an interpretation that the variation in CO2 excretion pattern mainly originates from the variation in GE rather than the postgastric events. On this basis, the relevance of OBT is ensured. 2. Conventionally, it has been explained that the time required for the absorption and oxidation processes is responsible for the apparent discrepancy between the CO2 recovery curve and the scintigraphic GE curve (1). However, this explanation contradicts the fact that the two processes are so rapid as to be bypassed effectively (1, 8). On the other hand, the distribution of CO2 operates much more slowly than the absorption and oxidation (Figure 1). It takes several hours to reach equilibrium between the blood and the slowly exchanging CO2 pool, and CO2 returns to the blood stream much later (7). This slow distribution prolongs the residence time of CO2 in the body, resulting in delayed exhalation of CO2. In addition, the barrier to elimination also delays CO2 exhalation. These are the more likely reasons for the discrepancy between OBT and scintigraphy. Accordingly, the half-emptying time, determined from the CO2 recovery profile, inherently involves the time for not only GE but also the distribution and elimination (3). Thus, the reliability of the halfemptying time is limited, despite its widespread use. For a more realistic estimation of GE, it is necessary to offset the additional time due to distribution and elimination. For this purpose, the deconvolution technique (8) and the Wagner– Nelson method (5) may be available. The deconvolution describes mathematical separation of a GE flow curve from a global CO2 excretion curve, and the separated GE profile yields an accurate half-emptying time comparable with a scintigraphic half-time. The Wagner–Nelson analysis allows estimation of the rate at which CO2 appears
TL;DR: The 13C‐caffeine breath test is a non‐invasive, quantitative test of liver function and can be used as a stand-alone test for liver function evaluation.
Abstract: Summary
Background : The 13C-caffeine breath test is a non-invasive, quantitative test of liver function.
Aim : To determine the utility of the 13C-caffeine breath test in chronic hepatitis B virus and its ability to monitor response to lamivudine.
Methods : Forty-eight chronic hepatitis B virus patients and 24 controls underwent the 13C-caffeine breath test. In 28 patients commenced on lamivudine, 13C-caffeine breath tests were performed at 1 week (n = 12) and after 1 year of therapy.
Results : Patients with Metavir F0–1 fibrosis (2.30 ± 1.02 Δ‰ per 100 mg caffeine) had a 13C-caffeine breath test similar to controls (2.31 ± 0.85, P = 0.96). However, patients with F2–3 fibrosis (1.59 ± 0.78, P = 0.047) and cirrhotic patients (0.99 ± 0.33, P = 0.001) had a decreased 13C-caffeine breath test. Fibrosis correlated best with the 13C-caffeine breath test (rs = −0.62, P < 0.001). The 13C-caffeine breath test independently predicted significant (F ≥ 2) and advanced (F ≥ 3) fibrosis and yielded the greatest area under the receiver operating characteristic curve (0.91 ± 0.04) for predicting advanced fibrosis. The 13C-caffeine breath test was unaltered by 1 week of lamivudine but improved by 61% (P < 0.001) in responders to long-term lamivudine, whereas in those with viraemia and elevated alanine aminotransferase, values remained stable or deteriorated.
Conclusion : The 13C-caffeine breath test distinguishes chronic hepatitis B virus-related fibrosis and detects improvement in liver function in response to long-term lamivudine.
TL;DR: The reproducibility of the 13C‐urea breath test (13C‐UBT) and its ability to reflect the level of Helicobacter pylori‐associated inflammation were assessed.
Abstract: Background: The purpose of the present paper was to assess the reproducibility of the 13C-urea breath test (13C-UBT) and its ability to reflect the level of Helicobacter pylori-associated inflammation.
Methods: Asymptomatic H. pylori-positive subjects (n = 21) performed the 13C-UBT six times. The H. pylori-positive symptomatic subjects (n = 55) performed the 13C-UBT and had antral biopsies taken for histopathology, culture, urease activity assay and myeloperoxidase activity assay.
Results: No significant intraindividual variation in 13C-UBT results were observed for the asymptomatic subjects. The 13C-UBT results were significantly higher in symptomatic subjects with a moderate to severe gastritis compared to a mild gastritis and to no inflammation (34.5 ± 4.4 vs 17.7 ± 2.8 vs 1.7 ± 0.1, respectively, P < 0.01). The 13C-UBT results significantly correlated with urease (r = 0.55) and myeloperoxidase activity (r = 0.82) but not with bacterial load.
Conclusion: The 13C-UBT is a reproducible determinant of H. pylori infection and non-invasively assesses the severity of antral inflammation.
© 2004 Blackwell Publishing Asia Pty Ltd