Urea Breath Test Values Research Articles

Comparative diagnostic performance of rapid urease test with the sweeping method versus tissue sampling method after Helicobacter pylori eradication (with video)

The rapid urease test (RUT) is widely used to detect Helicobacter pylori infection; however, it is not preferred as a monitoring strategy after eradication owing to its low sensitivity. In this study, we evaluated the diagnostic performance of RUT using the sweeping method, which overcomes the limitations of conventional tissue sampling methods after eradication. Patients who received H pylori eradication treatment were enrolled. Each of the sweeping and conventional methods was performed on the same patients to compare diagnostic performance. Urea breath test (UBT), histology, and polymerase chain reaction were performed to determine true infection. Logistic regression analysis was conducted to investigate reasons for discrepancies between the results of the 2 methods. In 216 patients, the eradication success rate was 68.1%, and the sensitivity and specificity of the sweeping method were 0.812 and 0.912, respectively, whereas those of the conventional method were 0.391 and 0.993, respectively (P< .05 for all). The area under the receiver operating characteristic curve for the sweeping method was higher than that for the conventional method (0.862 vs 0.692, P< .001). The mean time to H pylori detection for the sweeping method was 4.7 ± 4.4 minutes and 12.3 ± 16.1 minutes for the conventional method (P< .001). The risk for inconsistent results between the 2 methods was the highest for UBT values of 1.4‰ to 2.4‰ (odds ratio, 3.8; P= .016). The RUT with the sweeping method could potentially replace the tissue sampling method as a test to confirm H pylori eradication and be an alternative option to UBT for patients requiring endoscopy.

Effectiveness of Probiotic on Eradication Helicobacter Pylori Gastritis in Children

Background: Helicobacter pylori (H. pylori) is one of the causes of intestinal and gastric ulcers or one of the factors causing gastric malignancy. The prevalence of H. pylori infection is more than 80% in developing countries. Probiotics provide beneficial effects on the host?s health when administered in an adequate amount. Lactobacillus and Bifidobacteria are the most commonly used as probiotics. H.pylori colonization is interfered with by regular ingestion of L. acidophilus, and the urea breath test values decreased by approximately 10% four weeks after treatment. Objective: To assess the effectiveness of probiotic in eradication of H. pylori gastritis in children along with triple therapy Methods: This clinical trial design in children with H. pylori gastritis in a network hospital in Medan. Sampling was carried out from August 2019 - April 2020 with randomization techniques and double-blind in children suffering from H. pylori gastritis based on history, physical examination, H. pylori stool antigen (HpSA) test and endoscopy. Mc Nemar test analysis was performed to assess the difference effectiveness of drugs in the two groups. Result: From 33 children who received probiotics 31 children eradicated and from 31 children who did not receive probiotics, 29 children were eradicated. From 33 children who received probiotics, 6 children had side effects. From 31 children who did not receive probiotics, 22 children had side effects such as nausea/vomiting, abdominal pain, and diarrhea. There was no significant difference between probiotics and triple therapy with only triple therapy (p = 1,000). However, there was a significant difference in reducing the side effects of nausea/vomiting and diarrhea in the probiotic group (p = 0.015). Conclusion: There were no significant differences between administering probiotics plus triple therapy with triple therapy only to eradicate H. pylori gastritis in children. However, there were significant differences in the probiotic group in reducing the symptoms of side effects.

Sex differences in urea breath test results for the diagnosis of Helicobacter pylori infection: a large cross-sectional study

BackgroundHelicobacter pylori causes peptic ulcer disease and gastric cancer only in a subset of infected persons. Sex differences were shown in results of urea breath test (UBT), a commonly used test for the diagnosis of H. pylori infection. However, factors that might explain these differences, or affect UBT values, are not fully understood. We examined differences in UBT values between H. pylori-infected men and women while adjusting for background characteristics such as age, body mass index (BMI), and smoking.MethodsA cross-sectional study was undertaken using coded data from the computerized database of Maccabi Health Services in Israel. Included were adults examined for UBT during 2002–2012 and were found H. pylori positive (UBT > 3.5‰). Multivariable linear mixed models were performed to assess the relationship between sex and UBT quantitative results, while adjusting for background characteristics.ResultsA total of 76,403 patients were included (52% of examined patients during the study period). Adjusted mean UBT value was significantly higher in women 33.8‰ (95% CI 33.4, 34.1) than in men 24.9‰ (95% CI 24.5, 25.3). A significant (P < 0.001) interaction was found between sex and smoking, showing diminished sex-differences in UBT results in smokers. Adjusted mean UBT values increased significantly with age and decreased with BMI, and it was higher in people who lived in low vs high socioeconomic status communities and lower in smokers vs non-smokers.ConclusionsSystemic differences exist between men and women in quantitative UBT results. Host-related and environmental factors might affect UBT quantitative results. These findings have clinical implications regarding confirmation of the success of H. pylori eradication after treatment in various subgroups.

Accuracy of urea breath test in Helicobacter pylori infection: meta-analysis.

To quantitatively summarize and appraise the available evidence of urea breath test (UBT) use to diagnose Helicobacter pylori (H. pylori) infection in patients with dyspepsia and provide pooled diagnostic accuracy measures. We searched MEDLINE, EMBASE, Cochrane library and other databases for studies addressing the value of UBT in the diagnosis of H. pylori infection. We included cross-sectional studies that evaluated the diagnostic accuracy of UBT in adult patients with dyspeptic symptoms. Risk of bias was assessed using QUADAS (Quality Assessment of Diagnostic Accuracy Studies)-2 tool. Diagnostic accuracy measures were pooled using the random-effects model. Subgroup analysis was conducted by UBT type (13C vs 14C) and by measurement technique (Infrared spectrometry vs Isotope Ratio Mass Spectrometry). Out of 1380 studies identified, only 23 met the eligibility criteria. Fourteen studies (61%) evaluated 13C UBT and 9 studies (39%) evaluated 14C UBT. There was significant variation in the type of reference standard tests used across studies.Pooled sensitivity was 0.96 (95%CI: 0.95-0.97) andpooled specificity was 0.93 (95%CI: 0.91-0.94). Likelihood ratio for a positive test was 12 and for a negative test was 0.05 with an area under thecurve of 0.985. Meta-analyses were associated with a significant statistical heterogeneity that remained unexplained after subgroup analysis. The included studies had a moderate risk of bias. UBT has high diagnostic accuracy for detecting H. pylori infection in patients with dyspepsia. The reliability of diagnostic meta-analytic estimates however is limited by significant heterogeneity.

Value of the &lt;sup&gt;13&lt;/sup&gt;C-Urea Breath Test for Detection of Gastric &lt;i&gt;Helicobacter&lt;/i&gt; spp. Infection in Dogs Undergoing Endoscopic Examination

Urea breath test (UBT) using an infrared spectral analyzer is widely used for non-invasive and rapid detection of gastric Helicobacter spp. in human, but not veterinary medicine. The main purposes of this study were to determine the reference range of the UBT in dogs and to evaluate its clinical usefulness. To address the first aim, 6 healthy laboratory beagles were subjected to UBT and upper gastrointestinal endoscopy. Gastric endoscopic biopsy samples from the antrum, corpus and fundus were examined for Helicobacter spp. by polymerase chain reaction (PCR) testing, rapid urease test (RUT), histology and cytology. Amoxicillin, metronidazole and omeprazole were given to infected dogs for 14 days, and dogs that became Helicobacter-negative were used to determine the reference range for UBT. To address the second aim, 32 canine patients underwent UBT before upper gastrointestinal endoscopy, and the sensitivity and specificity of UBT were calculated based on our newly determined reference range using PCR as the gold standard for detection of Helicobacter spp. Initially, all 6 laboratory beagles were infected in all gastric regions and became uninfected after eradication. The mean ± 2 SD UBT value after eradication was 0.6 ± 1.8‰, and the reference range for UBT was determined to be less than 2.5‰. UBT was completed successfully in 27 patients. Using our reference range, UBT displayed 89% (16/18) sensitivity and 89% (8/9) specificity, indicating that UBT was quite useful for the detection of gastric Helicobacter spp. infection in dogs.

A Rapid Continuous-real-time 13C-Urea Breath Test for the Detection of Helicobacter pylori in Patients After Partial Gastrectomy

Before the development of efficient medications for peptic ulcer disease many patients were treated surgically by partial gastrectomy. The pathogenetic role of Helicobacter pylori was also not known yet. Some of these patients may therefore still harbor H. pylori in their remnant stomach as a carcinogenic agent for gastric cancer. This could be even more relevant for patients who were operated for tumors in the stomach. The efficacy of the urea breath test (UBT) is not clear in this population. To study the prevalence of H. pylori and to evaluate the sensitivity and specificity of the continuous UBT (BreathID) in postgastrectomized patients in Israel. In this system, the pH of the stomach is lowered by the addition of citric acid that may be beneficial in the smaller and more alkalic stomach. We compared retrospectively the results of our continous UBT with a rapid urease test (RUT) and the histology in all our patients who underwent gastroscopy for any clinical indication, and had a history of partial gastrectomy during the years 2002 to 2010. Only patients in whom H. pylori was tested by all the 3 methods during the same day were included in the study. We identified 76 such patients older than 18 years and performed a statistical analysis of all possibly related clinical data. The 3 methods were compared with each other. H. pylori was positive in 14/76 (18.4%) patients when histology was considered as the gold standard method. The positive predictive value of the continuous UBT and the RUT was 0.64 and 0.35, respectively. The negative predictive value was high by both the methods, 0.92 and 0.95, respectively. Weight loss was correlated with positivity for H. pylori (P=0.032) and a longer gastric stump was marginally related to H. pylori (P=0.071). There was no difference for H. pylori positivity between patients with Billroth I or Billroth II operations. Prevalence of H. pylori was not lower in patients who had partial gastrectomy several years earlier. The prevalence of H. pylori is considerable even several years after partial gastrectomy. The BreathID is reliable to exclude H. pylori after partial gastrectomy. The positive predictive value of the UBT is not very high but better than the RUT. We suggest that all positive patients found by the breath test should be treated. Our results support the view that alternative noninvasive methods, such as the stool antigen test should be further studied and compared with the BreathID in larger populations.

Effect of ecabet sodium treatment on urea breath test and stool antigen tests in volunteers with Helicobacter pylori infection

Ecabet sodium is reported to have a bactericidal effect on Helicobacter pylori and inhibit urease activity in vitro. Seven male volunteers (mean age, 51.3 years; range, 45-55 years) with H. pylori infection were medicated with 1 g ecabet sodium t.i.d. for 4 weeks. The urea breath test (UBT) was performed 10 times per person: before medication, seven times in 2 weeks, and once in the third and fourth weeks. Stool antigen tests (HpSA PLUS and Testmate pylori antigen) were performed five times per person: before medication and weekly during medication. The premedication UBT value ranged from 4.9 ‰ to 77.4 ‰ and from 2.9 ‰ to 44 ‰ at the end of the treatment period. Not one of the subjects had a negative UBT result during medication. The optical densities of the HpSA and Testmate pylori antigen tests ranged from 0.4 to > 3.0 premedication and from 0.0 to > 3.0 at the end of treatment. HpSA and Testmate pylori antigen were negative in two cases. In this study, ecabet sodium did not effect the results of UBT in volunteers with H. pylori infection. Ecabet sodium may influence stool antigens because in two of seven cases the H. pylori stool antigen tests returned negative results.

Influence of proton pump inhibitor treatment onHelicobacter pyloristool antigen test

To investigate the effects of proton pump inhibitor (PPI) treatment on stool antigen test using the TestMate pylori enzyme immunoassay. This study assessed 28 patients [16 men and 12 women; mean age (63.1 ± 5.9) years; range, 25-84 years] who underwent stool antigen test and urea breath test (UBT) before and after PPI administration. Using the UBT as the standard, the sensitivity, specificity and agreement of the stool antigen test in all 28 patients were 95.2%, 71.4%, and 89.3%, respectively, before PPI administration, and 88.9%, 90.9%, and 89.3%, respectively, after PPI treatment. Mean UBT values were 23.98% ± 5.33% before and 16.19% ± 4.75% after PPI treatment and, in 15 patients treated for ≥ 4 wk, were significantly lower after than before 4 wk of PPI treatment (12.58% ± 4.49% vs 24.53% ± 8.53%, P = 0.048). The mean optical density (A(450/630)) ratios on the stool antigen test were 1.16 ± 0.20 before and 1.17 ± 0.24 after PPI treatment (P = 0.989), and were 1.02 ± 0.26 and 0.69 ± 0.28, respectively, in the group treated for > 4 wk (P = 0.099). The stool antigen test was equally sensitive to the UBT, making it a useful and reliable diagnostic method, even during PPI administration.

Age and gender differences in urea breath test results

(13) C urea breath test (UBT) results, used for the diagnosis of Helicobacter pylori infection, fluctuate in different age groups. We characterized both the age- and gender-based trends of UBT results, from early childhood through late adulthood. A national H. pylori referral laboratory was screened for all positive UBTs during 2007-2008, determined as a delta over baseline (DOB) ≥ 3·5. Data were analysed with respect to both age and gender. In the studied period, 61,060 UBTs were performed and 24,237 were positive. After excluding multiple testing for an individual, a total of 21,767 positive results were analysed. The male/female ratio for positive UBTs was 1 : 1·77. DOB results decreased as age increased from a maximum of 38·6 ± 21 at age 3-5 years to 21·1 ± 12 at age 19-30 in females (P < 0·001) and from 30·0 ± 16 at age 6-10 years to 14·7 ± 8 at age 19-30 years in males (P < 0·0001). At this point, the values reached a nadir for both genders. In patients older than 60 years, old test results increased moderately (P < 0·003). In all age groups, except 6-10 years old, females had significantly higher UBT results than males. The decrease in mean UBT values already occurs during the first decade of life, and results increase following the sixth decade. Females have significantly higher results than males even in early childhood and throughout old age.

Helicobacter pylori antibiotic resistance and [13C]urea breath test values

A correlation between delta over baseline (DOB) values of the [(13)C]urea breath test (UBT) and Helicobacter pylori clarithromycin resistance has been reported, suggesting a possible predictive role of UBT in therapeutic outcome. However, available data are limited and conflicting. This study aimed to clarify this issue, assessing the possible relationship between H. pylori resistance towards different antibiotics (clarithromycin, metronidazole and levofloxacin) and UBT values. The data showed similar DOB values between susceptible and resistant strains for clarithromycin (46.9+/-32.3 vs 45.7+/-30.6; P=0.8), metronidazole (46.4+/-29.6 vs 47.4+/-37.9; P=0.8), and levofloxacin (45.0+/-30.2 vs 54.2+/-38.4; P=0.08). Likewise, comparable DOB values were observed between susceptible and multidrug-resistant strains (45.4+/-29.6 vs 54.8+/-44.8; P=0.1). In conclusion, our data failed to find a significant correlation between UBT values and H. pylori antibiotic resistance.

The effect of mastic gum on Helicobacter pylori: A randomized pilot study

Our aim was to study the effect of pure mastic gum on Helicobacter pylori (H. pylori) eradication in patients suffering from an H. pylori infection Fifty two patients were randomized to receive either 350mg three times a day (tid) of pure mastic gum for 14 days (Group A), or 1,05g tid of pure mastic gum (Group B) for 14 days, or pantoprazole 20mg twice a day (bd) plus pure mastic gum 350mg tid for 14 days (Group C) or pantoprazole 20mg bd plus amoxicillin 1g bd plus clarithromycin 500mg bd for 10 days (Group D). All patients harboured H. pylori before entering the study and that was confirmed by a (13)C urea breath test (UBT). H. pylori eradication was tested by a UBT 5 weeks after completion of the eradication regime. Eradication of H. pylori was confirmed in 4/13 patients in Group A and in 5/13 in Grour B. No patient in Group C achieved eradication whereas 10/13 patients in Group D had a negative UBT. There were no statistically significant differences in mean UBT values in Groups A, B, C although there was a trend in Group A (p=0.08) and in Group B (p=0.064). The difference was significant in Group D (p=0.01). All patients tolerated mastic gum well and no serious adverse events were reported. Mastic gum has bactericidal activity on H. pylori in vivo.

Urease-positive bacteria in the stomach induce a false-positive reaction in a urea breath test for diagnosis of Helicobacter pylori infection

This study investigated the influence of urease-positive non-Helicobacter pylori bacteria on the results of a urea breath test (UBT) to evaluate the diagnostic utility of a UBT using film-coated [(13)C]urea tablets. The UBT was performed in 102 patients treated with a proton pump inhibitor and antibiotics for the eradication of H. pylori. Urease-producing bacteria other than H. pylori were isolated and identified from the oral cavity and stomach. In 4/102 patients, the UBT gave false-positive results. These false-positive results were found to be caused by the presence of urease-positive bacteria in the oral cavity and stomach. Five bacterial species with urease activity (Proteus mirabilis, Citrobacter freundii, Klebsiella pneumoniae, Enterobacter cloacae and Staphylococcus aureus) were subsequently isolated from the oral cavity and/or stomach. As there was no correlation between the in vitro urease activity of urease-positive non-H. pylori bacteria and the UBT value, and all of the patients with a false-positive UBT result were suffering from atrophic gastritis, it is possible that the false-positive results in the UBT were a result of colonization of urease-positive bacteria and gastric hypochlorhydric conditions. Thus, for the diagnosis of H. pylori infection using a UBT, the influence of stomach bacteria must be considered when interpreting the results.

Interpretation of the 13C-urea breath test in the choice of second- and third-line eradication of Helicobacter pylori infection

The urea breath test (UBT) is one of the most accurate methods of assessing Helicobacter pylori status. The predictive value of the test is, however, uncertain. This study was a serial, prospective analysis of the change over time of UBT values after first-, second- and third-line treatments of patients with failed eradication therapy. One hundred thirty-four duodenal ulcer patients with persisting H. pylori infection after first-line triple therapy were enrolled in a cross-over manner to receive either pantoprazole (40 mg twice daily), amoxicillin (1000 mg twice daily), and clarithromycin (500 mg) or ranitidine bismuth citrate (400 mg twice daily), metronidazole (250 mg twice daily), and clarithromycin (500 mg twice daily) for 7 days. Forty-one patients with failed second-line treatment were randomized to receive third-line quadruple therapies with pantoprazole + amoxicillin and tetracycline (500 mg four times daily) and either nitrofurantoin (100 mg three times daily) or bismuth subsalicylate (120 mg four times daily). Breath tests were performed 6 weeks after therapy. The delta(13)CO(2) values ( per thousand) after primary, secondary, and tertiary treatment were analyzed, and the correlation between pretreatment values and the rate of H. pylori eradication was assessed. In patients with successful second-line treatment, UBT values decreased from 12.4 per thousand [confidence interval (CI), 9.7-15.7)] to 2.8 per thousand (CI, 0.9-2.5) (P=0.001), and in those with persistent infection, they increased from 13.2 per thousand (CI, 7.3-19.1) to 19.2 per thousand (CI, 13.4-25.0) (P=0.03). After a failed quadruple regimen, UBT values increased from 19.3 per thousand (CI, 16.2-22.4) to 25.8 per thousand (CI, 19.8-312.8) (P=0.03). The correlation between the pretreatment UBT values and the rate of eradication was negative for both second- and third-line therapies. Serial assessment showed that UBT values after successive treatments showed a marked tendency to increase over time in failed cases. The significance of this phenomenon must be further studied. It might indicate increased colonization, ongoing resistance, or urease gene overexpression. Higher pretreatment UBT values were associated with lower (<60%) eradication rates. In these cases, alternative/rescue therapies should be chosen.

Effect of Bifidobacterium bifidum Fermented Milk on Helicobacter pylori and Serum Pepsinogen Levels in Humans

Helicobacter pylori infection is an important risk factor for gastric diseases. Some probiotics are useful for suppressing H. pylori infection. Bifidobacterium bifidum YIT 4007 can improve the experimental gastric injury in rats and the disease stages on the gastric mucosa in peptic ulcer patients. We evaluated the fermented milk using a clone (BF-1) having the stronger ability to survive in the product than this parent strain to clarify the in vitro suppressive effect of BF-1 on H. pylori and the in vivo efficacy of BF-1 fermented milk on H. pylori and gastric health. In the mixed culture assay of BF-1 and H. pylori, the number of pathogens was decreased such that it was not detected after 48h in the Brucella broth with a decrease in pH values. In the cell culture experiment with human gastric cells, the H. pylori infection-induced IL-8 secretion was suppressed by the preincubation of BF-1. In a human study of 12-wk ingestion (BF-1 group, n=40; placebo group, n=39) with a randomized double-blind placebo-control design, the H. pylori urease activity and gastric situation were evaluated using a urea breath test (UBT) and the serum pepsinogen (PG) levels as biomarkers for inflammation or atrophy, respectively. In the H. pylori-positive subjects, the difference (ΔUBT) of the UBT value from the baseline value in the BF-1 group (n=34) was lower than that in the placebo group (n=35) at 8 wk. The baseline UBT values showed a negative correlation with ΔUBT values at 8 and 12 wk in the BF-1 group but not in the placebo. In the PG-positive subjects classified by the PG test method, the BF-1 group was lower in ΔUBT values than the placebo group at 8 and 12 wk. In the active gastritis class by PG levels, the BF-1 group was lower in their ΔUBT values than the placebo at 8 and 12 wk. The PG I levels in the BF-1 group were lower than the placebo at 12 wk. The PG II levels in the BF-1 group did not change during the ingestion period, but the placebo was increased. The PG I/II ratios slightly decreased from baseline at 12 and 20 wk in the BF-1 and placebo groups. These patterns were also observed in the H. pylori-positive subjects. The improving rates of upper gastrointestinal symptomatic subjects and total symptom numbers in the BF-1 group were higher than those in the placebo. These results indicate that BF-1 fermented milk may affect H. pylori infection or its activity, gastric mucosal situation, and the emergence of upper gastrointestinal symptoms.

Effect of the Folk Remedy, Bainiku‐ekisu, a Concentrate of Prunus mume Juice, on Helicobacter pylori Infection in Humans

Bainiku-ekisu, a concentrate of Japanese apricot (Prunus mume) juice, is a traditional Japanese folk remedy for treatment of dyspepsia since more than a thousand years ago. Fujita et al. previously reported in vitro antibacterial effect of Bainiku-ekisu to Helicobacter pylori. We conducted an in vivo pilot study to evaluate the possibility that Bainiku-ekisu may have an antibacterial effect on H. pylori in the human stomach. Consecutive 18 H. pylori-positive subjects were included. Approximately 130 mL 1% Bainiku-ekisu solution was ingested by the subjects twice a day for 12 weeks. Urea breath test (UBT) was performed before ingestion, and 2 and 12 weeks after starting ingestion of Bainiku-ekisu, and UBT values were compared. Bainiku-ekisu therapy resulted in a slight fall in UBT values after 2 weeks (from 30.1 +/- 6 to 23.5 +/- 6 in ITT analysis, p = .094; from 31.2 +/- 6 to 24.7 +/- 6 in PP analysis, p = .124) (data are shown with mean +/- SE). In two instances (11%), the UBT values became negative. Fourteen subjects completed the trial for 12 weeks and there was no significant change in UBT values (from 30.1 +/- 6 to 25.9 +/- 6 in ITT analysis, p = .450; from 35.6 +/- 6 to 31.4 +/- 7 in PP analysis, p = .555). Our results are consistent with the antibacterial effect of Bainiku-ekisu on H. pylori in the human stomach. However, the bacteria were not successfully eradicated with 2- or 12-week ingestion of a Bainiku-ekisu solution. Subsequent studies will need to identify a clinically useful regimen.

13C-urea breath test in the management of Helicobacterpylori infection

The urea breath test is a noninvasive and very accurate test for the diagnosis of Helicobacter pylori infection. However, false negative urea breath test results have been reported to occur in a considerable percentage of the individuals taking proton pump inhibitors; the interval needed to be completely confident that false negative tests had been excluded has varied among the different studies between 6 and 14 days. The impact of H 2-receptor antagonists on the accuracy of urea breath test remains controversial, although, in contrast with proton pump inhibitors, the data suggest that H 2-receptor antagonists, for the most part, have little effect on the result of the urea breath test. The urea breath test does not represent a suitable tool for estimating the density of H. pylori colonization. The only quantitative information to be obtained from the urea breath test is that the higher the δ value, the lower the probability of a false-positive urea breath test result. Although some authors have demonstrated a correlation between urea breath test values and histological lesions of the gastric mucosa, the practical utility of this relationship remains unclear. It has been suggested that the pretreatment urea breath test has the potential to identify patients who require modification of the standard therapeutic regimen (for example, prolonging the duration of treatment or increasing the pharmacological dose when bacterial density is high), but other studies could not confirm this relationship. Some studies have shown that the urea breath test is less accurate in patients who have undergone partial gastrectomy. Finally, in contrast with biopsy-based methods, which are responsible for a high number of false-negative results when used to diagnose H. pylori infection in patients with upper gastrointestinal bleeding, urea breath test seems not to be negatively influenced by the presence of this complication.

Effect of the Carbonic Anhydrase Inhibitor, Acetazolamide, on Helicobacter pylori Infection in vivo: A Pilot Study

Carbonic anhydrase inhibitors have been successfully used to treat peptic ulcers. Although carbonic anhydrase restriction does not inhibit Helicobacter pylori in vitro, recent studies suggest that carbonic anhydrase inhibition reduces the ability of H. pylori to survive in an acid environment as present in the stomach. In a pilot study, we examined the effect of acetazolamide 500 mg as twice a day for 4 days in volunteers with active H. pylori infection. Effectiveness was judged by changes in the results of the urea breath test. Eight H. pylori infected volunteers completed the test. No urea breath test reverted to negative and there was a trend for the urea breath test value to increase [e.g. delta over baseline (DOB) mean +/- SE increased from 50.9 +/- 13 at baseline to 64.9 +/- 13 at day 5] during treatment with acetazolamide. The potential effect of carbonic anhydrase inhibitors on acid secretion may prevent effect on H. pylori in vivo and/or the sites of infection at the surface of the stomach may have a pH higher for any postulated acid-dependent effect to have an effect clinically.

Suppressive Effect of Functional Drinking Yogurt Containing Specific Egg Yolk Immunoglobulin on Helicobacter pylori in Humans

Helicobacter pylori is a human pathogen that infects over 50% of the population worldwide. It is the most important etiologic agent of gastroduodenal ulcers and malignancies. Helicobacter pylori urease enzyme is considered the main factor for the organism's colonization in the gastroduodenal mucosa. Hens immunized with the purified urease produce a highly specific anti-H. pylori urease immunoglobulin (IgY-urease) in their egg yolks. Immunoglobulin Y-urease was stable at 60 to 65°C for 30min and at pH 4.0 for 7h. Its activity was lost at 80°C for 20min and at pH 2 for 4h. Specially designed functional drinking yogurt containing Lactobacillus acidophilus and Bifidobacterium spp. with 1% egg yolk IgY-urease was produced commercially. Immunoglobulin Y-urease activity showed stability in the product up to 7 d, and then decreased to 85% after 3 wk of storage. A clinical study was conducted to determine the effectiveness of IgY-urease yogurt to suppress infection in humans. Forty-two volunteers who tested positive for H. pylori using a 13C-urea breath test were recruited. A total of 450mL of IgY-urease (test group) or IgY-urease–free yogurt (control group) was consumed in 150-mL portions 3 times daily for 4 wk. Volunteers were tested after 2 and 4 wk; urea breath test values significantly decreased in the test group compared with the control group. The results indicate that suppression of H. pylori infection in humans could be achieved by consumption of drinking yogurt fortified with IgY-urease.

Dietary Amelioration of Helicobacter pylori Infection: Design Criteria for a Clinical Trial

Abstract The longitudinal stability of the urea breath test (UBT), which measures urease as a biomarker for infection with Helicobacter pylori (a major risk factor for gastric cancer), was evaluated in the environs of Tsukuba, Japan. 13C-UBT measurements were monitored at four time points in 46 free-living, H. pylori–infected, asymptomatic volunteers over a period of 7 weeks. Subjects were asked to refrain from eating cruciferous vegetables, which might confound interpretation of results. Their compliance was monitored using both dietary records and direct biochemical testing of overnight urine. There was large between-subject UBT variation in this population (logUBT mean, 3.34; SD, 0.67). Within-subject (longitudinal) UBT values were remarkably stable in about one-quarter of the subjects (coefficients of variations for these individuals were &amp;lt;21%), whereas coefficients of variations in the highest quartile of variability ranged from 40% to 80%. About half of the sequential UBTs (63 of 138 such measurement pairs) changed &amp;gt;10‰ “delta over baseline” between measurements. This study provides the elements to optimize the design of a clinical trial in this population to examine the efficacy of a dietary intervention to reduce H. pylori infection. The number of subjects required to detect a 30% difference in average UBT value is highly dependent on the baseline stability of UBT measurements. For the least variable quartile, as few as 12 subjects would be needed; for the most variable quartile, at least 147 subjects would be required in each arm.

Incidence and factors influencing on Helicobacter pylori infection recurrence

a) To determine the rate of H. pylori reinfection after successful eradication in a 4-year follow-up study; and b) To evaluate the contribution of different factors in the infection relapse. A total of 208 patients (age range 18-81 years; average 50 years; 87 women) who had been successfully treated for H. pylori infection were included. Annually, urea breath test was assessed to determine H. pylori status after eradication. Age, sex, rural/urban environment, smoking habit, treatment regimens against H. pylori and urea breath test values were evaluated. reinfection occurred in 9,6% of patients observed, 6,7% (14/208) in the first year, 1,9% (4/208) in the second year, 1% (2/208) in the third and 0% in the forth. Risk factors for infection recurrence were younger age and higher values of urea breath test in the multivariante analysis. annual reinfection rate was 2,4 pacients-year. Younger patients and higher values of urea breath test were factors associated with a higher rate of reinfection relapse. Annually, urea breath test should be performed to detect reinfection in order to avoid ulcer complications.