Factors affecting the validity of the 13C-urea breath test for in vivo determination of Helicobacter pylori infection status in a mouse model

Background. The mouse model using a human isolate of Helicobacter pylori is being widely accepted as an economical means of studying gastric infection. A noninvasive monitoring method would be useful for repeated testing to establish the time course of infection and the efficacy of treatments. In this study, we describe factors that affect interpretation of ¹³C urea breath test results for the assessment of H. pylori infection status in this model.
Materials and Methods. Female C57Bl/6 mice that underwent gavage with H. pylori or saline were breath-tested using 50 μg of ¹³C urea at intervals up to 2 months after inoculation. The generation of ¹³CO₂ (excess δ¹³CO₂) by infected mice was compared to that of uninfected controls. The effects of diet, fasting, and coprophagy on the reliability of the ¹³C urea breath test were quantitated.
Results. Both commercial and synthetic mouse diets exhibited marked in vitro urease activity. A minimum fasting time of 13 hours prior to breath testing significantly reduced this dietary contribution to excess δ¹³CO₂ values. The coprophagic tendency of the mice caused spuriously high excess δ¹³CO₂ counts in the breath of both control and H. pylori –infected mice.
Conclusions. Although the dietary contribution to spuriously high values of excess δ¹³CO₂ in mice breath-tested for H. pylori infection was reduced by fasting, the high nonspecific urease activity generated by coprophagy severely limited the reliability of the urea breath test in the assessment of H. pylori infection status.     

Four-day, twice daily, quadruple therapy with amoxicillin, clarithromycin, tinidazole and omeprazole to cure Helicobacter pylori infection: a pilot study

Background. The best regimen for the treatment of Helicobacter pylori infection has yet to be defined. Four-day quadruple therapy with tetracycline, metronidazole, bismuth, and a proton pump inhibitor has been shown to obtain a very high cure rate. However, the fact that it must be taken four times daily may interfere with compliance. The objective of the study was to test the efficacy and tolerability of a new 4-day therapy with 4 drugs taken every 12 hours to cure H. pylori infection.
Patients and Methods. Fifty-six consecutive patients with peptic ulcer disease and H. pylori infection were treated with an oral 4-day course with omeprazole (20 mg/12 hours), clarithromycin (500 mg/12 hours), amoxicillin (1 g/12 hours) and tinidazole (500 mg/12 hours). Efficacy of the treatment was determined at least 2 months after therapy either by biopsy (in the case of gastric ulcer) or by ¹³C-urea breath test. A second breath test was performed at least 6 months after therapy.
Results. Two patients were lost to follow-up. Forty-nine of the remaining 54 patients were cured at the first control [intention-to-treat cure rate: 87.5% (CI 95% 75–94%); per protocol cure rate: 90.7% (CI 95% 81–98%)]. Forty-three of these 49 cured patients returned for a second ¹³C urea breath-test at 6–12 months. Two of them were not cured, giving a long-term cure rate of 85.5% per protocol and 73.2% by intention-to-treat. Compliance was good, although 25 patients had mild side effects.
Conclusion. This particular four-day therapy is well tolerated, easy to follow, and achieves an acceptably high cure rate.     

Eradication of H. pylori with pantoprazole, clarithromycin, and metronidazole in duodenal ulcer patients: a head-to-head comparison between two regimens of different duration

Background. The study was conducted to compare the efficacy and tolerability of two pantoprazole-based triple therapies of different length in the eradication of H. pylori.
Methods. In this double-blind, multicenter parallel group comparison, H. pylori -positive patients were randomly assigned to either the PCM-7 group (7 days of pantoprazole 40 mg bid, clarithromycin 500 mg bid, metronidazole 500 mg bid) or the PCM-14 m group (modified 14 day therapy of the same regimen with metronidazole only given for 10 days due to labeling reasons). H. pylori status was determined by urease test, histology, culture, and ¹³C-urea breath test. Treatment outcome was assessed 6 weeks after intake of the last study medication.
Results. The following eradication rates were achieved: for PCM-7 in the MITT population 83% (89/107), in the PP population 84% (81/97); for PCM-14 m in MITT 87% (92/106), in PP 88% (91/104). Ulcer healing rates were: for PCM-7 in MITT population 99% (106/107), in the PP population 99% (96/97); for PCM-14 m in MITT 99% (105/106), in PP 99% (103/104). Gastrointestinal symptoms and gastritis scores decreased in both treatment groups. Equivalence of treatment regimens could be proven for all populations. In total, 64 patients reported adverse events. Five serious adverse events occurred, all unrelated to the study medication.
Conclusion. The two pantoprazole-based triple therapies tested in this study are equally effective in H. pylori eradication, ulcer healing and relief from ulcer pain. It is concluded that 7 days of triple therapy are generally sufficient.     

13C urea breath test with nondispersive isotope-selective infrared spectrometry: reproducibility and importance of the fasting status

Background. The ¹³C urea breath test (¹³C-UBT) is the most convenient method for diagnosing Helicobacter pylori infection noninvasively. Nondispersive isotope-selective infrared spectrometry (NDIRS) is an inexpensive and easy alternative to mass spectrometry. The objective of this study was to evaluate: (1) the reproducibility of the ¹³C-UBT as performed by using the NDIRS method; (2) the repeatability of bags analysis and the impact of delayed analysis; and (3) the need for fasting status for the ¹³C-UBT.
Methods. The ¹³C-UBT was performed with 75 mg urea labeled with ¹³C, with breath samples collected at times 0 and 30 minutes. Results are expressed as delta over baseline (0/00). Fifty-three patients underwent two successive ¹³C-UBTs with an interval of 48 to 72 hours. The 106 collected bags were randomly reanalyzed immediately or 72 hours later. In 26 volunteer subjects, the ¹³C-UBT was performed both in a fasting condition and after a nonstandardized meal. The reproducibility was assessed by the method of Bland and Altman.
Results. The mean of difference between two successive tests was 0.14 0/00 (standard deviation, 0.90), and the coefficient of repeatability was 1.80 (confidence interval, 95%). The difference between two successive analyses was always less than 2.2% of the initial value. The coefficient of variation between two successive tests for the influence of a meal was 11.24.
Conclusion. The ¹³C-UBT as performed by using NDIRS is reproducible, analyses can be delayed up to 72 hours, and the test must be performed in fasting conditions.     

Comparison of One or Two Weeks of Lansoprazole, Amoxicillin, and Clarithromycin in the Treatment of Helicobacter pylori

Background The simplest, most effective, and least expensive Helicobacter pylori therapy remains to be determined. Two weeks of 30 mg lansoprazole bid, 1 gm amoxicillin bid, and 500 mg clarithromycin bid (LAC2) had been shown to be an effective therapy for H. pylori. The aim of this study was to assess whether 1 week of this regimen (LAC1) would have a similar efficacy.
Materials and Methods. H. pylori -positive patients assessed histologically, by rapid urease test, microbiologically, and by a ¹³C-urea breath test (¹³C-UBT) were randomized to receive either LAC1 or LAC2 in a single-center open study. Patients were interviewed 1 to 3 days after completion of therapy to evaluate adverse events and compliance. Efficacy was determined by ¹³C-UBT at least 4 weeks after antibiotic therapy.
Results. Seventy evaluable patients were randomized to receive LAC1 (n = 33) and LAC2 (n = 37). Of the 33 LAC1 patients, 30 (91%) were treated successfully (95% confidence interval (CI) = 76–98%), compared with 32 of 37 (86%) in the LAC2 group (95% CI = 71–96%). There was no difference in efficacy between the two groups (Fisher's exact test p = 1.0; 95% CI =–10.3%–19.2%). Patients taking LAC1 experienced significantly fewer severe adverse events than those taking LAC2 (Mann-Whitney U test). One of 64 patients had primary resistance to clarithromycin, and treatment was unsuccessful in this case. Six of the 7 remaining treatment failures developed secondary resistance to clarithromycin.
Conclusions. LAC1 is as effective as LAC2 and is associated with less toxicity. Posttreatment clarithromycin resistance is common in patients who do not experience success with therapy.     

Twenty-Minute Fasting Version of the US 13C-Urea Breath Test for the Diagnosis of H. pylori Infection

Background. In large-scale multi-center clinical trials, the US ¹³C-urea breath test (UBT) has proven to have a sensitivity and specificity of approximately 95%. Ingestion of a meal to delay gastric emptying has advantages of increasing the level of signal as well as prolonging the duration of significantly increased ¹³C excretion, at the expense of requiring 40 to 60 minutes to complete the test. Our aim was to explore the utility of the ¹³C-UBT with a total duration of 30 minutes or less.
Methods. After a baseline breath sample was obtained, 125 mg of ¹³C-urea was given in 100 ml of water, and additional breath samples were taken after 20 and 30 minutes. The results of the UBT were compared to histological assessment, culture, and the rapid urease test. ¹³C-UBTs were carried out on normal volunteers who underwent gastroscopy during which six mucosal biopsies were taken. Three biopsies were for histological evaluation (Genta stain), two for culture, and one was for agar gel rapid urease testing. The UBT was conducted 2 to 3 days either before or after the endoscopic procedure.
Results. The cutoff value for a positive UBT was enrichment of 2.4Δ%₀ (delta over baseline). Of the 66 tests, 51%₀ were Helicobacter pylori -positive. There were no false positive UBTs and only two false negative UBTs at 20 minutes (sensitivity, 96%; specificity, 100%). At 30 minutes, one other UBT was false negative (gray zone of 2.36%₀.) (sensitivity, 94%; specificity, 100%).
Conclusion. These results suggest that omission of the meal and shortening the duration of the US ¹³C-UBT to 20 minutes still may maintain excellent specificity and sensitivity of the test.     

Controlled trial of the effect of cinnamon extract on Helicobacter pylori

Background. Helicobacter pylori has been associated with the pathogenesis of antral gastritis, duodenal ulcer, and gastric lymphoma. Eradication of H. pylori has been shown to reverse or prevent relapse of these diseases. Antimicrobials employed in the eradication of H. pylori are not without adverse effects. Newer treatment modalities, therefore, are required. In vitro studies have shown the effectiveness of cinnamon extract against H. pylori and its urease. In this pilot study, we tested the activity of an alcoholic extract of cinnamon in a group of patients infected with H. pylori.
Materials and Methods. Fifteen patients (11 women, 4 men) aged 16 to 79 years were given 40 mg of an alcoholic cinnamon extract twice daily for 4 weeks; eight patients aged 35 to 79 (7 women, 1 man) received placebo. The amount of H. pylori colonization was measured by the ¹³C urea breath test before and after therapy.
Results. The mean urea breath test counts in the study and control groups before and after therapy were 22.1 and 23.9 versus 24.4 and 25.9, respectively. The cinnamon extract was well tolerated, and side effects were minimal.
Conclusions. We concluded that cinnamon extract, at a concentration of 80 mg /day as a single agent, is ineffective in eradicating H. pylori. Combination of cinnamon with other antimicrobials, or cinnamon extract at a higher concentration, however, may prove useful.     

Inhibition of Helicobacter pylori Infection in Humans by Lactobacillus reuteri ATCC 55730 and Effect on Eradication Therapy: A Pilot Study

Background:  Several studies report an inhibitory effect of probiotics on Helicobacter pylori .
Aim:  To test whether Lactobacillus reuteri ATCC 55730 reduces H. pylori intragastric load in vivo, decreases dyspeptic symptoms, and affects eradication rates after conventional treatment.
Materials and Methods:  In a double-blind placebo-controlled study, 40 H. pylori -positive subjects were given L. reuteri once a day for 4 weeks or placebo. All underwent upper endoscopy, ¹³C-urea breath test, and H. pylori stool antigen determination at entry and ¹³C-urea breath test and H. pylori stool antigen (used as both qualitative and semiquantitative markers) after 4 weeks of treatment. Sequential treatment was administered subsequently to all.
Results:  In vivo, L. reuteri reduces H. pylori load as semiquantitatively assessed by both ¹³C-urea breath test δ -value and H. pylori stool antigen quantification after 4 weeks of treatment ( p <  .05). No change was shown in patients receiving placebo. L. reuteri administration was followed by a significant decrease in the Gastrointestinal Symptom Rating Scale as compared to pretreatment value ( p <  .05) that was not present in those receiving placebo ( p =  not significant). No difference in eradication rates was observed.
Conclusions:  L. reuteri effectively suppresses H. pylori infection in humans and decreases the occurrence of dyspeptic symptoms. Nevertheless, it does not seem to affect antibiotic therapy outcome.     

13C-urea breath test and gastric mucosal colonization by Helicobacter pylori in children: quantitative relation and usefulness for diagnosis of infection

Objective. Because in children Helicobacter pylori colonization could differ as compared to that in adults, gastric metabolism of urea and the reliability of the breath test must be evaluated. The aim of this study was to quantify the relationship between breath test and colonization.
Methodology. We studied data from 50 endoscopies performed in 39 children and adolescents (20 girls, 19 boys, aged 3–18 years); 28 were infected with H. pylori. Biopsies were analyzed for histological and microbiological diagnosis of infection and for quantitative antral culture of H. pylori. A ¹³C urea breath test was performed on the same day as that of endoscopy ( n = 33) or delayed between 2 and 90 days ( n = 17).
Results. Using a cut-off value of 3 δ‰, sensitivity was 96.5%, and specificity was 91.5%. The three children showing discrepancies between breath test and biopsy results had a δ‰ value close to the cut-off. For the 26 cases with a positive culture, we noted a significant correlation (r = 0.63; p < .001) that was not affected by the delay between breath test and gastroscopy.
Conclusion. This quantitative relation between bacterial density and δ‰ permits increasing the reliability of the test by interpreting carefully those results that approach the cut-off value.     

The Ideal Therapy Must Be Def ined in Each Geographical Area: Experience with a Quadruple Therapy in Spain

Background. Multiple therapeutic combinations have been tested to determine the optimal regimen(s) for Helicobacter pylori eradication, leading to very different results depending on the geographical area. Our goal was to evaluate the efficacy of a "quadruple" therapy with omeprazole, tetracycline, bismuth and metronidazole in our area.
Materials and Methods. We investigate 106 consecutive patients with active peptic ulcer disease (duodenal, gastric or both) and Helicobacter pylori infection. One-week therapy with omeprazole 20 mg b.i.d., tetracycline hydrochloride 500 mg q.i.d., colloidal bismuth subcitrate 120 mg q.i.d., and metronidazole 250 mg t.i.d was prescribed. Between the days 30 and 40 after treatment ended follow-up endoscopy was performed. Eradication was defined as both negative urease test and histology. Between days 90 and 360 a ¹³C urea breath test was performed in 100 patients.
Results. Of the 106 patients in the study, 91 had duodenal ulcer, 12 had gastric ulcer, and 3 had both. Side effects were observed in 25% of the cases. Eradication was achieved in 87.7% (93/106; CI 79.9–93.3). Healing was obtained in 95.2% (100/105; CI 89.2–98.4); 97.8% (CI 92.4–99.7) in those eradicated and 75% (CI 42.8–94.5) in non-eradicated ( p < .01).
Conclusions. Quadruple therapy with omeprazole, tetracycline, bismuth subcitrate and metronidazole achieves healing rates up to 95–100%. The 87.7% eradication rate obtained suggests that the regimen we used is a reasonable therapeutic alternative in our area.     

Addition of metronidazole to rabeprazole-amoxicillin-clarithromycin regimen for Helicobacter pylori infection provides an excellent cure rate with five-day therapy

Background. New triple therapy for eradication of Helicobacter pylori based on a proton pump inhibitor (PPI) provides a cure rate of approximately 90% with few adverse effects. Recently, a PPI-based quadruple therapy, which consists of a PPI plus bismuth-based triple therapy for 7 days, has been studied, and a sufficient eradication rate has been achieved. However, a shorter duration results in improved compliance. In this study, newly developed short-term, simple twice-daily quadruple therapy consisting of rabeprazole, amoxicillin, clarithromycin, and metronidazole (RACM) was compared with a PPI-based triple-therapy regimen for eradication of H. pylori.
Patients and Methods. This study was designed as a randomized open, prospective single-center study. Of a total of 105 H. pylori –positive patients, 55 received the RACM regimen for 5 days (rabeprazole, 10 mg bid; amoxicillin, 750 mg bid; clarithromycin, 200 mg bid; and metronidazole, 250 mg bid), and 50 received the RAC regimen for 5 days (rabeprazole, 10 mg bid; amoxicillin, 750 mg bid; and clarithromycin, 200 mg bid). Cure of the infection was assessed by HpSA ( H. pylori stool antigen immunoassay) 1 month after completion of therapy.
Results. The rates of eradication of H. pylori by RACM versus RAC were 94.5% (95% CI, 85–99) versus 80.0% (95% CI, 66–90) by intention-to-treat analysis; 98.1% (95% CI, 90–100) versus 87.0% (95% CI, 74–95) by all-patients-treated analysis; and 98.1% (95% CI, 90–100) versus 86.7% (95% CI, 73–95) by per-protocol analysis. No major adverse effects were reported, and 98.0% of patients reported complete compliance.
Conclusions. The simple twice-daily and short-term quadruple regimen for only 5 days provided an excellent eradication rate. Compliance with the regimen was high, and serious adverse effects were few. Therefore, the RACM regimen can be considered as safe and effective.     

Urea Breath Test in Children: The United States Prospective, Multicenter Study

Background: The urea breath test (UBT) is generally considered the gold standard for the diagnosis of Helicobacter pylori infections in adults.
Goals: To investigate the utility and accuracy of urea breath testing in children from the United States.
Methods: Children scheduled to undergo upper gastrointestinal endoscopy for various clinical symptoms underwent a ¹³C-UBT using the US standard protocol for adults. Results were compared with rapid urease testing (RUT), culture, and histology. H. pylori positivity was defined according to the FDA, Division of Anti-Infective Drug Products criteria, i.e. positive culture and/or positive RUT and histology. H. pylori negativity was defined as all tests negative. Results were evaluated by delta over baseline (DOB) and urea hydrolysis rate (UHR).
Results: A total of 176 children from five centers were evaluated; 48 were infected. Compared to the defined standard, the results with the UBT based on delta over baseline (DOB) cut-off value (positive: ≥ 2.4‰) showed that the sensitivity and specificity of the UBT were 97.9% and 96.1%, respectively. Based on the UHR cut-off value (positive: ≥ 10.0 µg/min), the sensitivity and specificity were 95.8% and 99.2%. In young children (2- to 5-year olds), sensitivity and specificity of UHR method were higher than the DOB method (100% and 100% vs 100% and 82.4%, respectively).
Conclusion: The US standard ¹³C-UBT proved to be both simple and accurate for the diagnosis of H. pylori infections in children. The UHR method to calculate of ¹³C-UBT result provided excellent results for children of all ages.     

Factors that affect results of the 13C urea breath test in Japanese patients

Background. The ¹³C urea breath test (UBT) is considered to be the most accurate way of diagnosing Helicobacter pylori infection. Our objective was to investigate the accuracy of the UBT in Japanese patients and the association of UBT values with histological findings.
Materials and Methods. A total of 169 consecutive patients were studied by endoscopy with histology, by serology with IgG antibody and test serum pepsinogen (PG), and by UBT. The association between UBT values and histological findings and the PG I / II ratio were analyzed in H. pylori –positive patients.
Results. Of 169 Japanese patients, 135 were H. pylori –positive on both histology and serology analysis, 27 were H. pylori –negative on both histology and serology analysis, and 7 patients showed differing results. Using a cutoff value of 2.5‰, test sensitivity was 100%, while specificity was 96%. Among the 135 H. pylori –positive patients, a significant relation was observed between UBT value and H. pylori colonization density of the corpus and antrum, neutrophil activity of the antrum, atrophy, and intestinal metaplasia of the corpus in the H. pylori –positive patients. Also, UBT values correlated with the PG I /II ratio. In multivariate analysis, the PG I /II ratio was the most important factor related to UBT values (odds ration [OR], 4.99; 95% confidence interval, 1.60–15.55).
Conclusions. The UBT is an accurate method for detecting H. pylori infection in the Japanese population, which shows a high prevalence of atrophic gastritis. Values are affected by H. pylori infection and by the severity of atrophic gastritis.     

δ13C variability of benthic algae: effects of water colour via modulation by stream current

1. Increased water motion is expected to reduce boundary layer diffusion resistance of autotrophs, thereby enabling greater isotopic discrimination against ¹³C such that lower δ¹³C values (ratio of ¹³C : ¹²C) should ensue. A field test of this hypothesis was undertaken by sampling benthic algae in streams of differing current speed.
2. Contrary to the expected negative relationship between δ¹³C and water motion, filamentous benthic algae were found to exhibit higher δ¹³C values in rapid water.
3. Under conditions of low current in the streams studied, concentrations of dissolved organic carbon as measured by water colour are elevated through the microbial decomposition of largely terrestrial organic matter. Photoassimilation of this respired carbon by benthic filamentous algae generates ¹³C‐depletion and lower δ¹³C values, and appears to be substantial enough in the streams used in the present study to override the competing influence of water motion on boundary layer thickness.     

Effect of Smoking and Histological Gastritis Severity on the Rate of H. pylori Eradication with Omeprazole, Amoxicillin, and Clarithromycin

Background. The combination of omeprazole, amoxicillin, and clarithromycin is a common regimen against Helicobacter pylori. Several recent studies have shown that smoking, high intragastric acidity, and the degree of histological gastritis are associated with H. pylori eradication failure.
Materials and Methods. One hundred and thirty-seven H. pylori –positive patients were treated with a 1-week regimen composed of omeprazole, 20 mg once daily; amoxicillin, 500 mg; and clarithromycin, 200 mg thrice daily. Success of the treatment was evaluated by histology and the ¹³C-urea breath test at least 4 weeks after completion of therapy. Data about age, gender, alcohol intake, smoking habits, and previous proton pump inhibitor intake were collected in patient interviews. We evaluated fasting gastric pH and the degree of histological gastritis before eradication of H. pylori.
Results. The overall eradication of H. pylori at 4 weeks was successful in 98 of 137 patients (72%). On the multivariate analysis, a low grade of inflammation in the antrum ( p ≤ .01; 95% confidence interval [CI], 2.34–16.75), low grade of activity in the fundus ( p ≤ .05; 95% CI, 1.31–9.65), and smoking ( p ≤ .05; 95% CI, 1.27–6.82) were the significant independent factors predicting treatment failure.
Conclusions. These findings indicate that H. pylori eradication therapy with omeprazole, amoxicillin, and clarithromycin is less effective in patients who smoke and more effective in patients with high scores of antral inflammation and fundal activity at baseline biopsy.     

Changes in feeding niche widths of perch and roach following biomanipulation, revealed by stable isotope analysis

1. We made an empirical test of a recent proposal that feeding niche widths might be determined as variance of stable isotope values. We determined δ ¹³C and δ ¹⁵N values of perch ( Perca fluviatilis ), roach ( Rutilus rutilus ) and their prey from a biomanipulated lake, when the mass removal of fish led to reduced inter- and intra-specific competition and increases in zooplankton abundance and body size.
2. After the first fish removals, both perch and roach mean δ ¹³C values decreased and mean δ ¹⁵N values increased, indicating a greater diet contribution from pelagic sources.
3. Variances of both δ ¹³C and δ ¹⁵N values first increased in both fish populations, indicating a wider food spectrum and expanded feeding niche width following reduced fish abundances. Observed changes were greater for the perch population than for roach.
4. In 2006, the perch population abruptly changed its diet so that most individuals were primarily consuming the abundant young-of-the-year fish, and this was reflected in significantly reduced variances of both δ ¹³C and δ ¹⁵N values.
5. We conclude that isotopic variance can indeed reflect changes in feeding niche width and offers a promising way to study such general ecological concepts.     

Seasonal and annual changes in leaf δ13C in two co-occurring Mediterranean oaks: relations to leaf growth and drought progression

1. Changes of δ¹³C and its relation to leaf development, biochemical content and water stress were monitored over a 2 year period in two co-occurring Mediterranean oak species: the deciduous Quercus pubescens and the evergreen Quercus ilex .
2. The time course of leaf δ¹³C showed different patterns in the two species. Young Q. pubescens leaves had a high δ¹³C and a marked decrease occurred during leaf growth. In contrast, leaves at budburst and maturity did not differ significantly in the case of Q. ilex . We suggest that the difference between δ¹³C of young leaves was linked to differential use of reserves of carbon compounds in the two species.
3. δ¹³C values of mature leaves were negatively correlated with minimum seasonal values of predawn water potential, suggesting that a functional adjustment to water resources occurred.
4. There was a significant correlation between individual δ¹³C values for two successive years. This interannual dependence showed that δ¹³C rankings between trees were constant through time.     

Impact of Quadruple Regimen of Clarithromycin Added to Metronidazole-Containing Triple Therapy Against Helicobacter pylori Infection Following Clarithromycin-Containing Triple-Therapy Failure

Background: The establishment of an optimal second-line regimen for Helicobacter pylori infection is required. Although quadruple therapy should overcome resistance to either clarithromycin or metronidazole, the effects of a quadruple regimen in second-line therapy are unknown. This study aims to evaluate the efficacy of triple therapy composed of proton pump inhibitor/amoxicillin plus metronidazole with the combined additive effects of clarithromycin as a second-line quadruple therapy against H. pylori infection.
Materials and Methods: Participants were 104 patients in whom first-line therapy containing proton pump inhibitor-amoxicillin-clarithromycin failed. Before starting second-line therapy, patients underwent endoscopy to obtain H. pylori strain for antibiotic susceptibility tests. Patients were randomized to receive rabeprazole (10 mg), amoxicillin (750 mg), and metronidazole (250 mg), either with clarithromycin (200 mg; RAMC group) or without (RAM group); all treatments were administered twice daily for 7 days. H. pylori eradication was confirmed by ¹³C-urea breath tests performed 2 to 3 months post-therapy.
Results: As shown by intention-to-treat/per-protocol analyses, the cure rates for H. pylori infection were 88.5%/93.9% and 82.7%/84.3% for the RAMC and RAM groups. Although the study probably had an insufficient power to show a significant difference between the cure rates of the two regimens, the eradication rates showed a clear trend in favor of the RAMC group. There were no severe side-effects in any group.
Conclusions: In Japan, the RAMC regimen is thought to be a promising alternative strategy for second-line eradication of H. pylori infection.     

Comparative Treatment of Helicobacter pylori–Positive Duodenal Ulcer Using Pantoprazole at Low and High Doses Versus Omeprazole in Triple Therapy

Background. Helicobacter pylori eradication has become the standard treatment for peptic ulcer disease. H. pylori –eradicating triple therapy with omeprazole plus two antibiotics has been used until recently; however, the efficacy of pantoprazole and antibiotics for H. pylori eradication has not been researched thoroughly until now. The aim of this randomized clinical trial was to verify the efficacy of triple oral therapy comparing the effects of pantoprazole using two different doses versus omeprazole twice daily in H. pylori eradication, in ulcer healing and relapses, and in gastritis improvement.
Materials and Methods. We enrolled 243 patients with H. pylori– positive duodenal ulcer and randomized them into three treatment groups: 84 patients (group Ome40) were assigned to receive omeprazole, 20 mg twice daily, plus amoxicillin, 1 gm twice daily, and clarithromycin, 500 mg twice daily for 10 days; 79 patients (group Pan40) were treated with pantoprazole, 40 mg daily, plus amoxicillin and clarithromycin at the same doses as those of group Ome40; and 80 patients (group Pan80) were treated with pantoprazole, 40 mg twice daily, plus amoxicillin and clarithromycin at the same doses as those of group Ome40.
Results. Ulcer healing was observed in 81 of 84 patients (96.4%) in group Ome40; in 66 of 79 patients (83.5%) in group Pan40; and in 77 of 80 patients (96.2%) in group Pan80. H. pylori was eradicated in 79 of 84 patients (94%) in group Ome40; in 63 of 79 patients (79.7%) in group Pan40; and in 75 of 80 patients (93.7%) in group Pan80.
Conclusions. We found that 10-day triple therapy with amoxicillin, clarithromycin, and either pantoprazole, 80 mg daily, or omeprazole, 40 mg daily, is highly effective in ulcer healing and is very well tolerated, achieving the 90% cure recommended for an ideal first-line anti– H. pylori positive duodenal ulcer treatment regimen.     

Comparison of 7-day and 14-day proton pump inhibitor-containing triple therapy for Helicobacter pylori eradication: neither treatment duration provides acceptable eradication rate in Korea

BACKGROUND AND AIMS: Although triple combination therapy containing a proton pump inhibitor (PPI) and two antibiotics is considered as a standard regimen for the first-line anti-Helicobacter pylori treatment, there are still debates on the ideal duration of treatment. The aim of this study was to compare the efficacies of 7-day and 14-day PPI-containing triple therapy. MATERIALS AND METHODS: This study was performed in a randomized, multicenter, prospective manner. After upper gastrointestinal endoscopy, H. pylori-infected patients with a gastric ulcer and/or a duodenal ulcer were randomly assigned to a PAC7 group (omeprazole 20 mg or equivalent dose of other PPIs, amoxicillin 1000 mg, and clarithromycin 500 mg twice daily for 7 days) or to a PAC14 group (the same regimen as the PAC7 group but for 14 days). H. pylori status was evaluated by (13)C urea breath test 5 weeks after anti-ulcer treatment completion. RESULTS: A total of 598 patients were enrolled; 337 were randomized to the PAC7 group and 261 to the PAC14 group. The two groups were comparable in terms of baseline characteristics. The eradication rates of the PAC7 group were not inferior to those of the PAC14 group in both intention-to-treat analysis (71.2% vs. 75.5%) and per-protocol analysis (83.6% vs. 86.6%). Incidences of adverse events were comparable. CONCLUSIONS: Although the 7-day PPI-containing triple anti-H. pylori therapy is not inferior to the 14-day therapy, neither treatment duration provides acceptable eradication rate reaching 90% in per-protocol analysis. New combination regimen with higher efficacy should be developed as a first-line eradication therapy for H. pylori in Korea.