Factors influencing the eradication of Helicobacter pylori with triple therapy

Comparative study of Helicobacter pylori eradication rates of twice-versus four-times-daily amoxicillin administered with proton pump inhibitor and clarithromycin: a randomized study

BACKGROUND

Proton pump inhibitor (PPI)-containing triple therapy with clarithromycin and amoxicillin is now a standard regimen for Helicobacter pylori eradication in Korea. Amoxicillin has time-dependent bactericidal activity against H. pylori; we therefore assumed a dosing schedule of amoxicillin would affect the eradication rate of H. pylori. The purpose of this study was to evaluate and compare the efficacy of different amoxicillin dosing schedules for the eradication of H. pylori.

MATERIALS AND METHODS

One hundred and eighty-six patients with H. pylori infection were eligible for this study. Patients were randomly assigned to one of two regimens: amoxicillin 1000 mg with clarithromycin 500 mg and omeprazole 20 mg twice daily for 2 weeks (BID group, n = 93), or amoxicillin 500 mg four times daily with clarithromycin 500 mg and omeprazole 20 mg twice daily for 2 weeks (QID group, n = 93). The success of H. pylori eradication was evaluated 4-5 weeks after completing treatment.

RESULTS

Overall eradication rate was 90.3%, and eradication rates were 91.4% in the BID group and 89.2% in the QID group (p = 0.62). Compliances was 95.7% in the BID group and 93.5% in the QID group (p = 0.516); this was the only factor that significantly affected H. pylori eradication in this study. Side effects in both groups were generally mild.

CONCLUSIONS

Amoxicillin regimens with PPI and clarithromycin are found to be equally effective and safe in both the BID and QID groups for H. pylori eradication. Therefore, considering patient's comfort, we recommend a twice daily amoxicillin regimen.

Providing an endoscopy report to patients after a procedure: a low-cost intervention with high returns

BACKGROUND

Providing a procedure report to patients after endoscopy is inconsistently practiced by clinicians.

OBJECTIVE

To evaluate the effect of providing a procedure report to patients after an outpatient endoscopy.

OUTCOME MEASUREMENTS

Demographic data, including age, sex, race, and endoscopic procedures. Assessments one week after the procedure included anxiety, satisfaction, recall of endoscopic findings and recommendations, and compliance.

DESIGN

A prospective, randomized, single-center, investigator-blinded study. Anxiety was measured by using the Beck Anxiety Inventory; satisfaction was measured with a modified American Society for Gastrointestinal Endoscopy survey, which was validated as part of this study, and recall and compliance was measured by a patient interview, during which responses were compared with the original endoscopy report.

SETTING AND PATIENTS

Single university outpatient endoscopy laboratory. Between June and September 2005, 115 patients were randomized, and 83 completed this protocol.

RESULTS

The two groups were equally matched, except the intervention group (received report) was older (54.4 vs 50.7 years; P = .037). Receipt of an endoscopy report reduced postprocedure anxiety (P = .001) and improved recall of findings and recommendations (P = .001 for both). Satisfaction was very high for all patients and was unaffected by receipt of a report. Patients older than 60 years had significantly lower satisfaction scores by approximately 6 points (P = .004). Some subcategories of compliance were significantly better in the intervention group, but there was no effect on the number of patients who complied with all recommendations.

LIMITATION

Small number of patients.

CONCLUSIONS

The receipt of an endoscopy report at discharge reduces postprocedure anxiety, improves recall of findings and recommendations, and may increase compliance. This inexpensive and safe practice should be routinely adopted.

Double-dose, new-generation proton pump inhibitors do not improve Helicobacter pylori eradication rate

BACKGROUND

Up to present, omeprazole plus two antibiotics are used for Helicobacter pylori eradication therapy . Few studies have compared double-dose new-generation, proton pump inhibitors (PPI) with omeprazole. Therefore, we conducted a randomized, prospective study to evaluate differences in H. pylori eradication rates by PPI type.

MATERIAL AND METHODS

Between January 2006 and December 2006, 576 consecutive patients with proven H. pylori infection were enrolled prospectively. Four different PPIs [omeprazole 20 mg b.i.d. (old generation), or pantoprazole 40 mg b.i.d., rabeprazole 20 mg b.i.d., or esomeprazole 40 mg b.i.d. (new generation)] were added to clarithromycin (500 mg b.i.d.) and amoxicillin (1 g b.i.d.) for 1 week.

RESULTS

By intention-to-treat analysis, no difference was found between the eradication rates of these four PPIs: 64.9% (omeprazole, n = 148), 69.3% (pantoprazole, n = 140), 69.3% (rabeprazole, n = 140), and 72.9% (esomoprazole, n = 148). When eradication rates were analyzed according to whether patients had an ulcer or not on a per-protocol basis, no difference was found between the eradication rates of the four PPIs. However, side-effects were more common in the esomeprazole-based triple therapy group than in the other groups (p < .05).

CONCLUSIONS

No convincing evidence was obtained that double-dose new-generation PPIs have better H. pylori eradication rates and tolerability than omeprazole.

High eradication rate of H. pylori with moxifloxacin-based treatment: a randomized controlled trial

INTRODUCTION

Eradication of Helicobacter pylori remains a problematic treatment issue in clinical practice. The intention is to find a treatment that achieves a high rate of eradication at a low price and treatment options that are now used give us the opportunity to achieve this goal. Recently published results showing a low rate of resistance and better compliance with moxifloxacin-based treatment regimens indicate the need to investigate its efficacy in H. pylori eradication. This study is based on proving the efficacy of moxifloxacin in H. pylori eradication within the triple therapy.

AIMS AND METHODS

The aim of the study was to compare the efficacy of one week of moxifloxacin-based treatment with the standard treatment for H. pylori eradication. Patients with H. pylori infection and non-ulcer dyspepsia (n = 277) were randomly divided into four groups to receive: moxifloxacin 400 mg/d, metronidazole 400 mg twice daily, lansoprazole 30 mg twice daily (MML group); moxifloxacin 400 mg/d, amoxicillin 1 g twice daily, lansoprazole 30 mg twice daily (MAL group); clarithromycin 500 mg twice daily, metronidazole 400 mg twice daily, lansoprazole 30 mg twice daily (CML group); clarithromycin 500 mg twice daily, amoxicillin 1 g twice daily, lansoprazole 30 mg twice daily (CAL group). The patients were assessed for prevalence of H. pylori using the CLO test, histology and culture on gastric biopsy samples obtained during upper gastrointestinal endoscopy before randomization and 4-6 weeks after completion of treatment. Bacterial sensitivity to clarithromycin and moxifloxacin was determined with the E-test.

RESULTS

265 (95.6%) patients completed the study forming the basis for PP analysis. Eradication rates of H. pylori in ITT and in PP analyses were: in the MML group 93.5% (58/62) and 96.7% (58/60), respectively; in the MAL group 86.4% (57/66) and 90.5% (57/63); in the CML group 70.4% (50/71) and 75.8% (50/66); and in the CAL group 78.2% (61/78) and 80.2% (61/76). Moxifloxacin treatment protocols were significantly more effective on both ITT and PP analyses than the clarithromycin based protocols with only one exception (MAL vs. CAL on ITT analysis). Among 238 patients (86% of the entire study group), strains showing primary resistance to clarithromycin were found in 10.8% and to moxifloxacin in 5.9%. Eradication of moxifloxacin sensitive/resistant strains was 98.1%/75% for MML (p < 0.01) and 91.1%/66.7% for MAL (p = n.s.); comparison of eradication of sensitive strains in MML and MAL regimens was 98.1%/91.1% (p < 0.05), and for resistant strains 75%/66.7% (p = n.s.). CML and CAL protocols did not differ in efficacy of eradication of clarithromycin sensitive or resistant strains.

CONCLUSION

Moxifloxacin-based triple therapies showed higher eradication rates with few side effects and good drug compliance when compared with standard H. pylori treatments. Moreover, the increased prevalence of clarithromycin resistance suggests that moxifloxacin-based regimens could be safe and effective options in treatment of H. pylori infection.

The need for long-term treatment of peptic ulcer

Some 10% of the population in Western countries will suffer a duodenal ulcer or gastric ulcer at some time in their lives. Although there has been an improvement in the survival rate of patients with peptic ulcer haemorrhage, the mortality is still approximately 10%. There is evidence to suggest that peptic ulcer disease is a life-long condition and that ulcers remain active with an unchanged potential for complications such as haemorrhage and perforation. Over the past 15 years anti-ulcer drugs with different mechanisms of action have been developed, and their use results in complete healing of an ulcer in four to eight weeks. However, most patients experience recurrence of their peptic ulcer after discontinuation of the healing therapy. Studies of continuous H2-receptor antagonist therapy have shown that recurrence occurs less frequently than in untreated patients, is largely asymptomatic, and is rarely characterized by haemorrhagic complications. Limited data on therapy for the eradication of Helicobacter pylori suggest that this may be an alternative approach for selected patients. As protection afforded by H2-receptor antagonists remains undiminished over the course of several years and is also observed in ulcers which have bled in the past, the implementation of long-term management with these agents constitutes a rational policy.

Effective regimens for the treatment of Helicobacter pylori infection

Successful Helicobacter pylori eradication therapy remains a challenge in medical practice. Currently, a proton pump inhibitor-based triple therapy containing clarithromycin, amoxicillin or nitroimidazole for 7 days is the recommended first-line treatment approach with an expected eradication success rate of approximately 80%. As a second-line treatment option in the case of failure, a ranitidine bismuth citrate-based quadruple therapy is currently recommended curing another 80% of patients, leaving a subset of patients with persistent H. pylori infection. For these patients, promising rescue options have been evaluated including regimens that contain rifabutin, quinolones, furazolidone or high-dose amoxicillin. The role of susceptibility testing is still under discussion. It is not generally recommended prior to first-line treatment but guidelines propose a role for culture and antibiotic sensitivity testing after failure of the second attempt. Meanwhile, data on the geographic distribution of resistance pattern are available and may guide therapeutic decisions with regard to the combination of antibiotics chosen for the individual patients aiming at 100% cure rate in each individual patient.

Antibiotic-taking experiences of undergraduate college students

PURPOSE

The purpose of this qualitative descriptive study was to explore the medication-taking experiences of undergraduate college students prescribed short-term antibiotic therapies and to describe factors influencing their adherence.

DATA SOURCES

Thirty-four undergraduate students prescribed antibiotics for treatment of an acute infectious illness at a large university health center were recruited to participate in this study. Semistructured telephone interviews were conducted after students finished their course of treatment. Qualitative descriptive content analysis was used to analyze the transcripts typed from the audio-taped phone interviews.

CONCLUSIONS

The main theme that emerged from the data was antibiotic-taking self-management. Most participants were able to adapt medication regimens into their daily routines, and used events in their day and specific reminder strategies to help them to remember to take their medications. This occurred despite an ever-changing class and work schedule and being prescribed complex, lengthy antibiotic regimens. Most dosing errors occurred during times when schedules changed or students were off campus during weekends or college breaks. A small number of students discontinued therapy early because of side effects or forgetfulness.

IMPLICATIONS FOR PRACTICE

By understanding factors that influence antibiotic adherence from a college student perspective, healthcare providers can suggest strategies to promote adherence that are tailored to the specific needs of this unique population.

In vitro activity of a novel antimicrobial agent, TG44, for treatment of Helicobacter pylori infection

Due to concerns about the current therapeutic modalities for Helicobacter pylori infection, e.g., the increased emergence of drug-resistant strains and the adverse reactions of drugs currently administered, there is a need to develop an anti-H. pylori agent with higher efficacy and less toxicity. The antibacterial activity of TG44, an anti-H. pylori agent with a novel structural formula, against 54 clinical isolates of H. pylori was examined and compared with those of amoxicillin (AMX), clarithromycin (CLR), and metronidazole (MNZ). Consequently, TG44 inhibited the growth of H. pylori in an MIC range of 0.0625 to 1 microg/ml. The MIC ranges of AMX, CLR, and MNZ were 0.0078 to 8 microg/ml, 0.0156 to 64 microg/ml, and 2 to 128 microg/ml, respectively. The antibacterial activity of TG44 against AMX-, CLR-, and MNZ-resistant strains was nearly comparable to that against drug-susceptible ones. In a pH range of 3 to 7, TG44 at 3.13 to 12.5 microg/ml exhibited potent bactericidal activity against H. pylori in the stationary phase of growth as early as 1 h after treatment began, in contrast to AMX, which showed no bactericidal activity at concentrations of up to 50 microg/ml at the same time point of treatment. TG44 at 25 microg/ml exhibited no antibacterial activity against 13 strains of aerobic bacteria, suggesting that its antibacterial activity against H. pylori is potent and highly specific. The present study indicated that TG44 possesses antibacterial activity which manifests quickly and is potentially useful for eradicating not only the antibiotic-susceptible but also the antibiotic-resistant strains of H. pylori by monotherapy.

Systematic review and meta-analysis: importance of CagA status for successful eradication of Helicobacter pylori infection

BACKGROUND

Some, but not all studies have provided evidence that the CagA status of Helicobacter pylori strains is a predictive factor for the outcome of eradication therapy.

AIM

To clarify the association between CagA status and eradication outcome.

METHODS

We included studies reporting the numbers of successful and failed cases in H. pylori-eradication therapy according to the CagA status. Fourteen studies (1529 patients) were included of 325 articles identified in the search. The pooled risk ratio for H. pylori-eradication failure in CagA-negative relative to CagA-positive strains and the pooled risk difference in eradication success between the two groups were used as summary statistics. Meta-regression was used for examining the source of heterogeneity.

RESULTS

The summary risk ratio for eradication failure in CagA-negative relative to CagA-positive was 2.0 (95% CI: 1.6-2.4, P < 0.001), corresponding with the summary risk difference for eradication success between the groups of 11% (95% CI: 3-19%, P = 0.011). Meta-regression analysis demonstrated that usage of polymerase chain reaction examination for CagA status and a high proportion of non-ulcer dyspepsia patients were factors for heterogeneity among studies.

CONCLUSIONS

Our meta-analysis confirmed the importance of the presence of CagA as a predictor for successful eradication of H. pylori.

Influence of smoking and CYP2C19 genotypes on H. pylori eradication success

CYP2C19 polymorphisms and smoking influence the efficacy of H. pylori eradication therapy, but interaction between the two have hitherto not been examined. A total of 142 H. pylori-positive patients who received triple drug therapy with lansoprazole, amoxicillin and clarithromycin were categorized into three groups with regard to diplotypes of CYP2C19: homozygous extensive metabolizer (homEM), heterozygous EM (hetEM), and poor metabolizer (PM). The overall success rate was 61.3%. Smoking was an independent risk factor of eradication failure (OR 2.81, 95% CI 1.14-6.91), whereas CYP2C19 polymorphisms were less influential. Among non-smokers, the homEM and hetEM groups showed worse eradication rates (58.5 and 67.3%) relative to PM (76.2%) as expected; however, an opposite trend was observed among smokers (homEM 50.0%, hetEM 46.7%, PM 20.0%), indicating possible interactions with CYP2C19 polymorphisms. Smoking has a greater influence on H. pylori eradication than the CYP2C19 genotype. Interaction between smoking and CYP2C19 should be examined in the future.

Efficacy of one-day quadruple therapy for H pylori infection in Chinese patients

AIM: To compare the efficacies of one-day quadruple therapy and seven-day triple therapy in Chinese patients.

METHODS: Sixty consecutive patients with nonulcer dyspepsia and confirmed H pylori infection were randomized to receive either omeprazole 40 mg, amoxycillin 1 g, and furazolidone 100 mg, all twice a day for 7 d or omeprazole 20 mg (at breakfast and dinner), amoxicillin 1 g, furazolidone 200 mg, and colloidal bismuth subcitrate 220 mg four times for only one day. H pylori status was determined before and at least 5 weeks after therapy by endoscopy with antral and corpus biopsies for rapid urease test and histology.

RESULTS: H pylori eradication was successful in 66.67% (20/30) patients in the 7-d group and in 36.67% (11/30) patients in the 1-day group (P = 0.037). Side effects were induced by the treatment in 13.3% (4/30) patients of each group, but these were all self-limiting, short-lasting, and did not require any specific treatment.

CONCLUSION: The one-day quadruple therapy is less effective than the one-week regimen in curing H pylori infection in Chinese patients.

Is there any correlation between 13C-urea breath test values and response to first-line and rescue Helicobacter pylori eradication therapies?

AIM

To study if there is a correlation between 13C-urea breath test values prior to treatment and the response to first-line and rescue Helicobacter pylori eradication therapies.

METHODS

Six-hundred patients with peptic ulcer or functional dyspepsia infected by H. pylori were prospectively studied. Pre-treatment H. pylori infection was established by 13C-urea breath test. Three-hundred and twelve patients were treated with first-line eradication regimen, and 288 received a rescue regimen. H. pylori eradication was defined as a negative 13C-urea breath test, 8 weeks after completion of treatment.

RESULTS

H. pylori eradication was achieved in 444 patients. No statistically significant differences were demonstrated when mean delta 13C-urea breath test values were compared between patients with eradication success and failure (49.4+/-33 versus 49.2+/-31). Differences in mean pre-treatment delta 13CO2 between patients with eradication success/failure were not demonstrated either when first-line or rescue regimens were prescribed. With the cut-off point of pre-treatment delta 13CO2 set at 35 units, sensitivity and specificity for the prediction of H. pylori eradication success was 43 and 60%. The area under the receiver operating characteristic curve evaluating all the cut-off points of the pre-treatment delta 13CO2 for the diagnosis of H. pylori eradication was 0.5. Finally, delta 13CO2 values did not influence the eradication in the logistic regression model.

CONCLUSION

No correlation was observed between 13C-urea breath test values before treatment and the response to first-line and rescue H. pylori eradication therapies. Therefore, we conclude that the quantification of delta 13CO2 prior to treatment is not useful to predict the success or failure of eradicating therapy.

Smoking increases the treatment failure for Helicobacter pylori eradication

PURPOSE

Treatment failure for Helicobacter pylori (H. pylori) eradication is encountered in approximately 10-20% of patients, and many studies have pointed to a link with smoking. To investigate the effects of smoking on eradication outcome, we performed a meta-analysis.

METHODS

A PubMed search was performed to retrieve articles published up to August 2005. Pooled odds ratio (OR) and differences rate for H. pylori eradication failure in smokers compared with nonsmokers were used as summary statistics. Meta-regression was used for examining the source of heterogeneity.

RESULTS

Twenty-two published studies (5538 patients), which provided information on eradication failure according to smoking status, were included in the analysis. The summary OR for eradication failure among smokers relative to nonsmokers was 1.95 (95% confidence interval [CI]: 1.55-2.45; P <.01). It corresponds with the differences in eradication rates between smokers and nonsmokers (8.4% [95% CI: 3.3-13.5%, P <.01]). Meta-regression analysis demonstrated that a high proportion of nonulcer dyspepsia patients in studies revealed a higher failure rate among smokers, compared with a low proportion of nonulcer dyspepsia.

CONCLUSIONS

Our meta-analysis demonstrated that smoking increases the treatment failure rate for H. pylori eradication.

Levofloxacin-based triple therapy versus bismuth-based quadruple therapy for persistent Helicobacter pylori infection: a meta-analysis

BACKGROUND

Levofloxacin-based triple therapy has been suggested as an alternative salvage therapy to bismuth-based quadruple therapy for persistent Helicobacter pylori (H. pylori) infection.

METHODS

A search of PUBMED, EMBASE, EBM Review databases and abstracts from recent Digestive Disease Week, United European Gastroenterology Week, and European Helicobacter Study Group conferences was performed. Randomized controlled trials (RCTs) comparing levofloxacin-based triple salvage therapy (levofloxacin + amoxicillin + PPI) to bismuth-based quadruple salvage therapy (bismuth + tetracycline + metronidazole + PPI) were selected for meta-analysis. Additionally, all prospective trials evaluating this levofloxacin-based triple therapy as salvage therapy were pooled to analyze optimal levofloxacin treatment duration and dosing. All selected trials confirmed prior treatment failure and post-salvage treatment eradication.

RESULTS

Four RCTs compared a 10-day regimen of levofloxacin-based triple therapy to 7-day bismuth-based quadruple therapy (n = 391 patients). Levofloxacin-based triple therapy was superior to quadruple therapy (RR = 1.41 [95% CI: 1.25-1.59]). Levofloxacin-based triple therapy was better tolerated than quadruple therapy with a lower incidence of side effects (RR = 0.51 [95% CI: 0.34-0.75]) and side effects prompting discontinuation of therapy (RR = 0.30 [95% CI: 0.10-0.89]). Eleven trials (n = 547 patients) evaluating levofloxacin-based triple therapy demonstrated higher eradication rates with 10-day versus 7-day regimen (87%[95% CI: 82%-92%]vs 68%[95% CI: 62%-74%]) yet eight trials (n = 477 patients) demonstrated no difference with 500 mg daily versus 250 mg b.i.d. dosing of levofloxacin (81%[95% CI: 78%-89%]vs 84%[95% CI: 66%-97%]).

CONCLUSIONS

A 10-day course levofloxacin triple therapy is more effective and better tolerated than 7-day bismuth-based quadruple therapy in the treatment of persistent H. pylori infection.

A study of 4- and 7-day triple therapy with rabeprazole, high-dose levofloxacin and tinidazole rescue treatment for Helicobacter pylori eradication

BACKGROUND

Helicobacter pylori treatment failure is becoming an emergent problem in clinical practice. Shorter treatment duration should improve compliance to therapy and keep an acceptable H. pylori eradication rate.

AIMS

To evaluate the efficacy of two rabeprazole, high-dose levofloxacin and tinidazole-based regimens as 'rescue' treatment for H. pylori eradication in an open-label, randomized, pilot study carried out in a clinical practice setting.

METHODS

Eighty-five consecutive patients who have previously failed at least one H. pylori eradication attempt were randomized to receive rabeprazole (20 mg, b.d.), levofloxacin (500 mg, b.d.) and tinidazole (500 mg, b.d.) either for 4 (4-day RLT, n = 42) or 7 days (7-day RLT, n = 43). Cure of H. pylori infection was assessed by means of 13C-urea breath test.

RESULTS

The 7-day RLT achieved 84% (95% CI: 69-93%) and 86% (95% CI: 72-95%) eradication rates in intention-to-treat and per-protocol analyses respectively. The shorter treatment obtained an 83% (95% CI: 69-93%) eradication rate in both intention-to-treat and per-protocol analysis. Both regimens were well tolerated, although patients who received the 4-day RLT reported fewer side-effects.

CONCLUSIONS

In patients who have previously failed at least one H. pylori eradication attempt, both 4- and 7-day rabeprazole, high-dose levofloxacin, tinidazole-based regimens are effective in curing the infection in more than 80% of patients.

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 delta 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.

A furazolidone-based quadruple therapy for Helicobacter pylori retreatment in patients with peptic ulcer disease

PURPOSE

Many of the currently used eradication regimens against Helicobacter pylori fail to cure the infection either due to antimicrobial resistance or to poor patient compliance. The infection leads to increased risk of developing potentially severe complications, such as gastric cancer. This study was aimed at assessing the efficacy and safety of a quadruple therapy with furazolidone for H. pylori retreatment.

METHODS

Patients who had failed one or more eradication regimens against H. pylori infection underwent upper gastrointestinal endoscopy. Biopsy specimens were taken from the gastric antrum and corpus for histology and for a urease test and. Patients received omeprazole 20 mg, bismuth citrate 240 mg, tetracycline 500 mg, and furazolidone 200 mg, all twice daily for 7 days. Therapeutic success was evaluated by endoscopy and biopsies 8 weeks after the end of treatment.

RESULTS

Sixty two patients were enrolled, and 58 completed the study. Under this protocol, H. pylori eradication was achieved in 39/58 patients (67%). Mild adverse events were reported.

CONCLUSION

The short quadruple therapy course with furazolidone is well tolerated, inexpensive, and effective in retreatment for H. pylori infection. It is a good option for developing countries.

Antibacterial activity of highly negative charged polyoxotungstates, K27[KAs4W40O140] and K18[KSb9W21O86], and Keggin-structural polyoxotungstates against Helicobacter pylori

The antibacterial activity of polyoxometalates (PMs) against Helicobacter pylori was investigated based on determinations of minimum inhibitory concentration (MIC) and fractional inhibitory concentration (FIC), time-killing of the bacteria, bacterial morphology and PM-uptake into the bacteria cell. The result of MIC values revealed that, of 13 PMs used in this study, highly negative-charged polyoxotungstates, such as K27[KAs4W40O140] and K18[KSb9W21O86], and Keggin-structural polyoxotungstates exhibited a potent antibacterial activity with the MIC values of less than 256 microg/ml. The former was the most active, and superior to metronidazole (MTZ) against MTZ-susceptible and resistant strains and also to clarithromycin (CLR) against CLR-resistant strains. In contrast, most of polyoxomolybdates showed little antibacterial activity with the MIC values of more than 256 microg/ml. The result of FIC index values indicated that the antibacterial polyoxotungstates had partially synergistic effect in combination with MTZ and CLR but indifferent effect in combination with amoxicillin (AMX). From the results of the time-killing and scanning electron microscope images, K27[KAs4W40O140] and K18[KSb9W21O86] proved the concentration-dependent bactericidal activity with the morphological change from bacillary form to coccoid form, while Keggin-structural K5[SiV(V)W11O40] showed the bacteriostatic activity with small change of morphology to coccoid form. The fluorescent X-ray analysis demonstrated that these polyoxotungstates were taken into the bacteria cell. It is pointed out that the Keggin-structure and/or high negativity polyoxotungstates are an important factor for the antibacterial activity against H. pylori.

Effectiveness of antiinfectives

BACKGROUND

Helicobacter pylori is one of the most common infections of mankind, with persistent colonization causing significant morbidity and mortality.

TREATMENT

First-line therapy, consisting of 7-day treatment with a proton pump inhibitor or ranitidine bismuth citrate, amoxicillin and clarithromycin, with second-line therapy, consisting of a proton pump inhibitor, bismuth, metronidazole, and tetracycline, in the case of failure, is chosen as the most cost-effective method of H. pylori eradication.

CONCLUSION

The effectiveness of these antiinfectives is limited by lack of compliance with treatment regimens, and increasing antibiotic resistance.

The relation of Helicobacter pylori to gastric adenocarcinoma and lymphoma: pathophysiology, epidemiology, screening, clinical presentation, treatment, and prevention

Helicobacter pylori infection may be the most common chronic bacterial infection worldwide; however, the prevalence varies between countries and is usually linked to socioeconomic conditions. Gastric cancer is one of the most frequent cancers in developing countries and usually about the seventh most common in developed countries. This article explores the relation of H. pylori to gastric adenocarcinoma and lymphoma. The pathophysiology, epidemiology, screening, clinical presentation, treatment, and prevention are discussed.

Comparison of the clinical feasibility of three rapid urease tests in the diagnosis of Helicobacter pylori infection

Rapid urease tests (RUTs) are a fast, accurate, and inexpensive method to diagnose H. pylori infection in the endoscopy suite. Of these, the CLO test is both common and widely used. The aim of our study was to evaluate the accuracy and positive reaction times of two new rapid urease tests (ProntoDry and HpONE) in comparison with the CLO test. Fifty-one patients (26 men, 25 women; mean age, 52.4 years) were included in this study, and all underwent esophagogastroduodenoscopy (EGD). None of the patients had received any prior H. pylori eradication therapy. H. pylori infection status was evaluated by histology, culture, 13C-UBT, and RUT. H. pylori infection was considered to be positive if the culture was positive or if two of the other three tests (histology, RUT, and 13C-UBT) were positive. If culture was negative and only one of the other three tests was positive, or if all four tests were negative, the result was interpreted as negative. Of these 51 patients, 2 were excluded and 29 (59.1%) were infected with H. pylori. The sensitivities, specificities, positive predictive values, and negative predictive values of the three RUTs were not significantly different. The mean positive reaction times of the three RUTs (CLO test, ProntoDry, and HpONE) were 67.8+/-12.0, 16.5+/-2.2, and 17.8+/-2.1 min, respectively. ProntoDry (P < 0.001) and HpONE (P < 0.001) had significantly faster reaction times than the CLO test, but there was no significant difference between ProntoDry and HpONE. Different media of RUTs may influence the rapidity of a positive reaction time. Both ProntoDry and HpONE were superior to the CLO test in terms of accuracy, reaction time, and cost-effectiveness.

Twice-daily standard dose of omeprazole achieves the necessary level of acid inhibition for Helicobacter pylori eradication. A randomized controlled trial using standard and double doses of omeprazole in triple therapy

Antibiotic resistances and level of acid inhibition may affect the outcome of eradicating regimens for H. pylori. To evaluate the impact of different degrees of acid inhibition on the efficacy of triple treatment, we treated 323 patients with H. pylori infection with clarithromycin and tinidazole plus omeprazole, either 20 mg bid or 40 mg bid. Gastric biopsies and antimicrobial susceptibility testing were performed. Eradication was evaluated by means of breath test. Eradication rates were (intention to treat and per protocol) 83.3 and 84.3% in patients receiving 40 mg omeprazole and 81.9 and 84.1% in those receiving 80 mg omeprazole. Culture was successful in 218 patients (68.7%). Resistance to clarithromycin and metronidazole were found in 13.7 and 20.6%, respectively. Eighteen further patients (8.2%) presented double resistance. Resistance was comparable across the two groups. In resistant patients the eradication rate was significantly lower (66.6% [95% CI, 56-76%], vs 86% [95% CI, 78-91%]; P = 0.001). Antibiotic resistance (OR, 2.73; 95% CI, 1.4-5.3) and smoking (OR, 2.68; 95% CI, 1.4-5.2) were independent predictors of eradication failure. Omeprazole, 20 mg bid, achieves the optimal acid inhibition in H. pylori eradication. Increasing antisecretory activity does not significantly enhance cure rates.

Synthesis and in vitro selective anti-Helicobacter pylori activity of pyrazoline derivatives

In order to develop new anti-Helicobacter pylori agents, a series of N1-substituted 3,5-diphenyl pyrazolines P1-P13 was prepared and evaluated for their antibacterial activity. All synthesized compounds showed little or no activity against different species of Gram-positive and Gram-negative bacteria of clinical relevance and against various strains of pathogenic fungi. The same derivatives exhibited a significant degree of activity against a range of H. pylori strains, including those resistant to the reference compound metronidazole. Among the prepared compounds those with an N1-acetyl group and a 4-methoxy substituent in the 5-phenyl ring showed the best activity against H. pylori metronidazole resistant strains in the 1-4 microg/mL MIC range.

Meta-analysis: the efficacy, adverse events, and adherence related to first-line anti-Helicobacter pylori quadruple therapies

BACKGROUND

Owing to rising drug-resistant Helicobacter pylori infections, currently recommended proton-pump inhibitor-based triple therapies are losing their efficacy, and regimens efficacious in the presence of drug resistance are needed.

AIMS

To summarize the efficacy, safety and adherence of first-line quadruple H. pylori therapies in adults.

METHODS

Meta-regression models identified factors explaining variation in the efficacy of first-line quadruple therapies from 145 treatment arms. Estimates of average efficacy were calculated within homogeneous groups.

RESULTS

Quadruple therapy containing a gastric acid inhibitor, bismuth, metronidazole and tetracycline was enhanced when omeprazole was included, treatment duration lasted 10-14 days, and when therapy took place in the Netherlands, Hong Kong and Australia. Treatment efficacy decreased as the prevalence of metronidazole resistance increased. Even in areas with a high prevalence of metronidazole resistance, this quadruple regimen eradicated more than 85% of H. pylori infections when it contained omeprazole and was given for 10-14 days. Furthermore, in the presence of clarithromycin resistance, this quadruple regimen eradicated 90-100% of H. pylori infections, while the currently recommended triple therapy containing clarithromycin, amoxicillin and a proton-pump inhibitor eradicated only 25-61% (P < 0.001). Adherence and adverse events for quadruple therapy were similar to currently recommended triple therapies.

CONCLUSIONS

Guidelines should include quadruple therapy with a proton-pump inhibitor, a bismuth compound, metronidazole and tetracycline among recommended first-line anti-H. pylori therapies.

13C-urea breath test for diagnosis of Helicobacter pylori infection in the elderly

Helicobacter pylori infection has a high prevalence in the elderly, but its characteristics and treatment in the geriatric population are not well defined. The aims of the study were to characterize geriatric patients according to referral patterns and results of the 13C-urea breath test (13C-UBT) and to investigate the results of treatment combinations for H. pylori eradiction. The 13C-UBT was performed with 75 mg urea labeled with 13C. Physicians who ordered the test completed a questionnaire covering demographic data, indication for the test, chronic use of a proton pump inhibitor, or nonsteroidal anti-inflammatory drug, and type of eradiction therapy. The study sample consisted of 2128 patients, aged 70-102 years, 958 (45%) men, referred for 13C-UBT. The test was positive on 697 (33%). History of peptic disease was the main indication for referral, following by validation of successful eradication, Israeli origin screening for gastric cancer, treatment with regimen containing metronidazole, history of peptic disease, and recurrence of symptoms were predictive factors for a positive 13C-UBT. Multivariate logistic regression analysis revealed a significant influence of eradication therapy on negative results. History of peptic disease and validation of successful eradication are the main indications for referral of the elderly for 13C-UBT. Our results are in accordance with the increase in metronidazole resistance of H. pylori stains and the cohort effect of H. pylori infection on the elderly Israeli-born population.

Use of imidazole-based eradication regimens for Helicobacter pylori should be abandoned in North India regardless of in vitro antibiotic sensitivity

BACKGROUND AND AIM

The purpose of this study was to compare the efficacy of tinidazole- versus clarithromycin-based triple regimens for eradication of Helicobacter pylori in North Indian patients of peptic ulcer disease, and to correlate the outcome with in vitro antibiotic susceptibility.

METHODS

One hundred and forty-six H. pylori-infected patients with active ulcer were included in the prospective, randomized study. A total of 70 patients received lansoprazole 30 mg b.d., amoxycillin 1000 mg b.d. and tinidazole 500 mg b.d. (LAT), and 76 patients received lansoprazole 30 mg b.d., amoxycillin 1000 mg b.d. and clarithromycin 500 mg b.d. (LAC) for 14 days. The H. pylori status was assessed by urea breath test, rapid urease test, and histology and antibiotic sensitivity pattern by Epsilometer test.

RESULTS

In per-protocol analysis of 112 patients the H. pylori eradication rate was 42.3% (95% confidence interval (CI): 0.29-0.56) in LAT, and 64.8% (95%CI: 0.52-0.78) in LAC (95%CI of difference of proportions: 0.13-0.33, P = 0.01). Ulcer healed in 69.2% in the LAT group (95%CI: 0.57-0.82) and 81.7% in the LAC group (95%CI: 0.72-0.92; P = 0.02). Antibiotic susceptibility testing was done in 31 patients. Metronidazole resistance was present in 41.9% isolates but was unrelated to the outcome of the LAT regimen.

CONCLUSION

Imidazole-based eradication regimens should be abandoned in North India regardless of in vitro susceptibility results.

Childhood H. pylori: disappearing disease or chronic infection?

Helicobacter pylori is one of the commonest chronic bacterial infections worldwide. It is acquired during childhood and its persistence has implications for health in later life. In adults, it is the principle cause of duodenal ulcer disease and there is evidence of an association between H. pylori and gastric cancer. However, most colonized people are asymptomatic. The prevalence of H. pylori increases with age but there is a striking difference between the rates in developed and developing countries. As no significant non-human or environmental source for this infection has been identified, person to person spread is almost certainly the main mode of transmission. Community nurses should be aware of this micro-organism as a potential cause of illness in children, and that they can play a role in promoting hygiene practices and educating families so that the risk of acquisition may be reduced. This review discusses the clinical features, prevalence, risk factors for transmission, diagnosis and treatment of H. pylori.

Comparison of H2-Receptor Antagonist-and Proton-Pump Inhibitor-Based Triple Regimens for the Eradication of Helicobacter Pylori in Chinese Patients with Gastritis or Peptic Ulcer

This study compared the efficacy of an H2-receptor antagonist (H2RA)- and a proton-pump inhibitor (PPI)-based triple regimen for the eradication of Helicobacter pylori infection. Chinese patients with H. pylori-associated gastritis or peptic ulcer were randomized to receive the H2RA-based triple regimen (20 mg famotidine, 1.0 g amoxicillin and 0.4 g metronidazole) or the PPI-based triple regimen (20 mg omeprazole, 1.0 g amoxicillin and 0.4 g metronidazole) both twice daily for 1 or 2 weeks. Successful eradication of H. pylori was determined by the 13C-urea breath test and gastric mucosa histology at least 4 weeks after completion of antibiotic therapy. Eradication rates were 56.0% and 76.9% for the 1-week H2RA- and PPI-based triple regimens, respectively, and 81.6% and 82.1% for the 2-week regimens, respectively. The H. pylori eradication rate for the 2-week H2RA regimen was significantly higher than that for the 1-week regimen, but there were no significant differences between the 1- and 2-week PPI regimens. The two regimens proved equally effective in eradicating H. pylori infection.

Role of antibiotic sensitivity testing before first-line Helicobacter pylori eradication treatments

BACKGROUND

The resistance of Helicobacter pylori to antibiotics has been advocated as a major cause of treatment failure, and antimicrobial sensitivity testing has been proposed to improve efficacy; however, its role before first-line therapy has not been investigated in detail.

AIM

To assess whether antimicrobial sensitivity testing improves the eradication rate of first-line anti-Helicobacter treatments and to compare the effectiveness of ranitidine bismuth citrate and omeprazole in the presence of H. pylori resistance to antibiotics.

METHODS

Two hundred and forty-two patients were assigned to either empirical or antimicrobial sensitivity testing-based treatment; within each group, subjects were further randomized to receive ranitidine bismuth citrate, 400 mg b.d., tinidazole, 500 mg b.d., and clarithromycin, 500 mg b.d., or omeprazole, 20 mg b.d., clarithromycin, 500 mg b.d., and amoxicillin, 1 g b.d., for 1 week, with substitution of the resistant antibiotic in the antimicrobial sensitivity testing-based treatment group.

RESULTS

Eradication rates were 67% [confidence interval (CI), 55-79%] in the empirical treatment group and 76% (CI, 65-87%) in the antimicrobial sensitivity testing-based group (P=N.S.). The overall success rate was 60% (CI, 51-69%) with omeprazole and 82% (CI, 73-91%) with ranitidine bismuth citrate (P<0.03); the latter overcame antibiotic resistance in 12 of 15 strains vs. zero of eight strains by omeprazole.

CONCLUSIONS

Antimicrobial sensitivity testing before first-line treatment does not improve the eradication rate, which is greater when ranitidine bismuth citrate is included in the treatment.

Randomized study of different 'second-line' therapies for Helicobacter pylori infection after failure of the standard 'Maastricht triple therapy'

BACKGROUND

Triple therapy with proton pump inhibitor, clarithromycin and amoxicillin and, in the event of eradication failure, quadruple therapy with proton pump inhibitor, bismuth, tetracycline and metronidazole have been proposed in Maastricht as the optimal sequential treatment of Helicobacter pylori infection.

AIM

To compare two second-line regimens with quadruple therapy.

METHODS

One hundred and eighty patients with a previous failed course of standard therapy were randomly given one of the following 7-day treatments: ranitidine bismuth citrate 400 mg b.d. plus amoxicillin 1 g b.d. and tinidazole 500 mg b.d. (RBCAT), pantoprazole 40 mg b.d. plus amoxicillin 1 g b.d. and levofloxacin 500 mg/day (PAL) and pantoprazole 40 mg b.d., bismuth citrate 240 mg b.d., tetracycline 500 mg q.d.s. and metronidazole 500 mg b.d. (PBTM). The eradication rate was assessed by 13C-urea breath test. Side-effects and compliance were evaluated by a standardized questionnaire and by counting returned medication.

RESULTS

The RBCAT, PAL and PBTM groups achieved mean intention-to-treat eradication rates of 85%, 63% and 83%, respectively (P<0.05 for PAL vs. either RBCAT or PBTM). Compliance was optimal in all patients, although side-effects were more commonly observed in the PBTM group than in the other two patient groups (P<0.0001).

CONCLUSIONS

Both RBCAT and PBTM can be used as second-line therapies. Conversely, PAL did not achieve satisfactory eradication rates.

Diagnostic methods for Helicobacter pylori detection and eradication

Helicobacter pylori is the principal cause of peptic ulcer disease and an important risk factor for the development of gastric cancer. The efficacy of 1 week triple therapies, which often have eradication rates of>90%, is undermined by poor patient compliance and bacterial antimicrobial resistance. The development of new anti-H. pylori therapies presents enormous challenges to clinical pharmacologists, not only in the identification of novel targets, but also in ensuring adequate drug delivery to the unique gastric mucus niche of H. pylori. Animal models of H. pylori infection have been developed but their clinical validity has yet to be established. Vaccination, to prevent or treat infection, has been demonstrated in animal models, but human studies have not been so encouraging.

13C-urea breath test, referral patterns, and results in children

BACKGROUND

The family is the core unit for Helicobacter pylori (Hp) infection. In most instances, Hp colonization occurs in early childhood, and correlates with socioeconomic parameters. Helicobacter pylori infection is highly prevalent in many countries, and may cause chronic gastritis and peptic ulcer in adults and in children. Gastritis induced by Hp may be associated with recurrent abdominal pain in children, and eradication of the bacterium may improve the clinical symptoms. AIM The primary aim of this study is to characterize the group of pediatric patients according to the referral patterns and results of 13C-urea breath test (13C -UBT) in our laboratory. The secondary aim is to investigate the result of different treatment combinations for Hp eradication.

METHODS

The 13C-UBT was performed with 75 mg urea labeled with 13C in 200 mL orange juice. Breath samples were collected at 0 and 30 minutes, and the results expressed as the change in the 13C/12C ratio at T30' minus T0' The cutoff for Hp eradication was 3.5. The physicians who ordered the test completed a questionnaire covering demographic data (age, gender, and origin), indication for the test was use of a proton pump inhibitor (PPI), and type of combination eradication therapy.

RESULTS

The study sample consisted of 1655 children, aged 1 to 18 years, 992 (59.9%) boys and 663 (40.1%) girls, from all parts of the country. The 13C-UBT was positive in 763 (46.1%). The prevalence of positive results was directly correlated with age. History of peptic disease was the main indication for the test, in 1346 (81.4%) cases. Details on eradication therapy were available for 435 children of whom 42.5% had a positive 13C-UBT, indicating a successful eradication rate of 57.5%. Compared with Israeli and American-European origin, children of Asian-African origin had a higher rate of referrals for reason of validation of successful Hp eradication, greater long-term PPI use, and a higher rate of 13C-UBT positivity. No significant difference was demonstrated between the triple therapy regimens used.

CONCLUSION

13C-UBT may be performed in children of all age groups. The main indication is a history of peptic ulcer disease. The prevalence of Hp infection increased with age and the only factor associated with increased Hp infection was Asian-African origin. The most frequent eradication therapy used in children is a combination of omeprazole, amoxicillin, and clarithromycin.

Treatment options for patients with Helicobacter pylori infection resistant to one or more eradication attempts

Proton pump inhibitor-based triple regimens fail to cure Helicobacter pylori infection in at least 10-23% of treated patients. Re-treatment strategies after initial failure remain poorly defined. Of the factors leading to eradication failure, patients' compliance, gender, primary resistance to clarithromycin and metronidazole, and intragastric bacterial load appear to be the most important in determining treatment outcome. Empirical re-treatment should depend mainly upon the antibiotics initially used, as re-administration of the same compound (namely, metronidazole and clarithromycin) is not recommended. Quadruple therapy is usually suggested in this situation, but there is some reluctance to use it in clinical practice on account of the high number of tablets to be taken and concern about side-effects. The use of ranitidine bismuth citrate instead of a proton pump inhibitor plus a bismuth compound in triple second-line regimens has recently proven to be highly effective. Finally, rifabutin-based triple therapies have been shown to be a promising rescue strategy in patients who have failed two or more eradication attempts.

Studies of compliance with delayed-release mesalazine therapy in patients with inflammatory bowel disease

BACKGROUND

Non-compliance with maintenance mesalazine therapy may be a risk factor for relapse in inflammatory bowel disease, but the prevalence and determinants of non-compliance are unknown.

AIM

To study the prevalence and determinants of non-compliance in patients with inflammatory bowel disease.

METHODS

Out-patients receiving delayed-release mesalazine were studied. Compliance was determined by direct enquiry and by analysis of urine samples for 5-aminosalicylic acid/N-acetyl-5-aminosalicylic acid. Potential determinants of compliance were assessed.

RESULTS

Ninety-eight patients were studied. Forty-two patients (43%) reported taking <80% of their prescribed dose. Logistic regression revealed the independent predictors of non-compliance to be three-times daily dosing [odds ratio (OR), 3.1; 95% confidence interval (CI), 1.8-8.4] and full-time employment (OR, 2.7; 95% CI, 1.1-6.9). Urine from 12 patients (12%) contained no detectable 5-aminosalicylic acid/N-acetyl-5-aminosalicylic acid, and 18 patients (18%) had levels below those expected. Depression was the only independent predictor of complete non-compliance (OR, 10.5; 95% CI, 1.8-79.0), and three-times daily dosing was the only independent predictor of partial non-compliance (OR, 3.7; 95% CI, 1.8-8.9). Self-reporting correctly identified 66% of patients judged to be non-compliant on urinary drug measurement.

CONCLUSIONS

Non-compliance with maintenance mesalazine therapy is common in patients with inflammatory bowel disease. Three-times daily dosing and full-time employment are predictors of partial non-compliance, whilst depression is associated with complete non-compliance. Self-reporting detects most non-compliant patients.

Is antimicrobial susceptibility testing necessary before second-line treatment for Helicobacter pylori infection?

BACKGROUND

An antimicrobial susceptibility test for Helicobacter pylori before second-line treatment is often performed, although whether the test is truly necessary remains unknown.

PATIENTS AND METHODS

Eighty-two patients with H. pylori infection for whom first-line treatment with a 1-week proton pump inhibitor/amoxicillin-clarithromycin (AC) regimen had failed were randomly assigned to two groups: those having or not having the susceptibility test before re-treatment. The cure rates for these two groups were compared.

RESULTS

Five of the 82 patients were excluded from the analysis. For 38 patients in the susceptibility-test group, we used what we considered the best regimen based on susceptibility testing: 10 patients [no resistance to clarithromycin (CAM)] received the lansoprazole-amoxicillin-clarithromycin regimen, 22 patients [19 CAM resistant, metronidazole (MNZ) susceptible; three failure of culture] were given the lansoprazole-amoxicillin-metronidazole (LAM) regimen, and six patients (both MNZ and CAM resistant) received dual therapy with omeprazole (OPZ) and amoxicillin (AMOX) in which the OPZ dose was determined by the CYP2C19 gene polymorphism. For 39 patients in the group with no susceptibility testing, LAM regimens were prescribed. The intention-to-treat (ITT)-based cure rates in the groups with and without susceptibility testing were 81.6% (95% confidence interval; 66-92%) and 92.4% (79-98%), respectively, and there was no significant difference between these two groups.

CONCLUSION

Susceptibility testing is not necessarily required before second-line therapy if the first-line treatment has been performed using proton pump inhibitor/AC regimens.

Triple vs. quadruple therapy for treating Helicobacter pylori infection: a meta-analysis

BACKGROUND

Triple therapy (proton pump inhibitor, clarithromycin and amoxicillin or an imidazole) is the first-line treatment for Helicobacter pylori infection. However, the effectiveness of triple therapy is decreasing due to the increase in antibiotic resistance. Quadruple therapy (proton pump inhibitor, tetracycline, metronidazole and a bismuth salt) is a very effective regimen even in areas of high prevalence of antibiotic resistance, and may be an alternative first-line treatment.

AIM

To compare triple vs. quadruple therapy for the first-line treatment of H. pylori infection.

METHODS

An extensive literature search was performed to identify randomized trials comparing triple vs. quadruple therapy. Selected trials were included in a meta-analysis using Review Manager 4.1.

RESULTS

Four studies met the inclusion criteria. Eradication rates with quadruple therapy were slightly higher in both the intention-to-treat (81% vs. 78%; odds ratio, 0.83; 95% confidence interval, 0.61-1.14) and per protocol (88% vs. 85%; odds ratio, 0.81; 95% confidence interval, 0.55-1.20) analysis, although the differences were not statistically significant. Nor were there significant differences in compliance or adverse effects between the therapies.

CONCLUSION

Triple and quadruple therapies seem to be roughly equivalent in terms of effectiveness, compliance and side-effects profile when administered as first-line treatment for H. pylori infection.

The use of proton pump inhibitors in children: a comprehensive review

Proton pump inhibitors (PPIs) belong to a group of chemically related compounds whose primary function is the inhibition of acid production in the final common metabolic pathway of gastric parietal cells. PPIs are highly selective and effective in their action and have few short- or long-term adverse effects. These pharmacologic features have made the development of PPIs the most significant advancement in the management of acid peptic related disorders in the last two decades. There are numerous published adult studies that describe the pharmacology, efficacy and safety of these anti-secretory agents; however, in the pediatric population, there are very few comparable studies, particularly multicenter studies with significant patient enrollment. In preparing this article, our aim was to perform a comprehensive review of the literature on the clinical pharmacology and use of PPIs in the pediatric population, and to briefly review some recent articles. Relevant literature was identified by performing MEDLINE/Pubmed searches from January 1990 to December 2001. Combinations of the following search terms were use to analyze these databases: proton pump inhibitor, children, pediatrics, gastroesophageal reflux disease (GERD), esophagitis, intestinal metaplasia, Helicobacter pylori, omeprazole, lansoprazole, pantoprazole, rabeprazole, esomeprazole, and safety. Abstracts from the 14th annual conference of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) 2001, and the Disease and Digestive Week 2001, were also included in the review. All pediatric studies reviewed were limited to either omeprazole or lansoprazole. The dosage range used for the management of GERD and related disorders with lansoprazole was 0.73-1.66 mg/kg/day (maximum 30 mg/day). The dosage range for GERD management using omeprazole was 0.3-3.5 mg/kg (maximum 80 mg/day). The dosage range for omeprazole used for H. pylori was 0.5-1.5 mg/kg/day, with a maximum dosage of 40 mg/day, and lansoprazole-containing regimens for H. pylori eradication used dosages ranging from 0.6-1.2 mg/kg/day, with a maximum dosage of 30 mg/day. Few severe adverse events were reported with the use of either drug. Eradication rates for H. pylori were 56-87% for lansoprazole-based triple therapy, and 75-94% for omeprazole-based eradication regimens. To date, there are no published controlled trials of sufficient power comparing the efficacy of the five commercially available PPIs in children, for a variety of acid peptic diseases. Studies suggest that PPIs are highly effective for the management of GERD and related disorders, and are a critically needed component of triple therapy to eradicate H. pylori. PPIs have a very good tolerability profile in adults and children, but long-term tolerability studies are needed, particularly in the pediatric population. Multicenter studies are critically needed to evaluate the second-generation PPIs, to compare PPI efficacy to each other, and to assess the importance of developmental and genetic pharmacology of these drugs in children with acid-peptic disease.

Effect of different proton pump inhibitors, differences in CYP2C19 genotype and antibiotic resistance on the eradication rate of Helicobacter pylori infection by a 1-week regimen of proton pump inhibitor, amoxicillin and clarithromycin

AIM

To investigate the effect of different proton pump inhibitors, S-mephenytoin 4'-hydroxylase (CYP2C19) genotype and antibiotic susceptibility on the eradication rate of Helicobacter pylori.

METHODS

One hundred and eighty-seven H. pylori-infected peptic ulcer patients were randomly treated with either rabeprazole (10 mg b.d.) or lansoprazole (30 mg b.d.) plus amoxicillin (750 mg b.d.) and clarithromycin (400 mg b.d.) for 1 week. The antibiotic susceptibility and CYP2C19 genotype (extensive or poor metabolizer) were investigated.

RESULTS

The eradication rates in the rabeprazole-amoxicillin-clarithromycin (RAC) and lansoprazole-amoxicillin-clarithromycin (LAC) groups were 75% and 69%, respectively, on an intention-to-treat basis, and 80% and 75%, respectively, on a per protocol basis. The eradication rate for clarithromycin-resistant strains was significantly lower than that for clarithromycin-sensitive strains (24% vs. 86%, P < 0.05). For clarithromycin-sensitive strains in the LAC group, there was a tendency for a lower eradication rate in extensive than poor metabolizers. The eradication rate in extensive metabolizers in the RAC group tended to be higher than that in extensive metabolizers in the LAC group (89% vs. 78%, P = 0.079726).

CONCLUSIONS

The success of the 1-week proton pump inhibitor-amoxicillin-clarithromycin regimen depends on the susceptibility of H. pylori to clarithromycin. Moreover, differences in CYP2C19 genotype influence the eradication rates of lansoprazole-based therapy, and the rabeprazole-based regimen has an advantage especially in extensive metabolizers.

Impact of clarithromycin resistance and CYP2C19 genetic polymorphism on treatment efficacy of Helicobacter pylori infection with lansoprazole- or rabeprazole-based triple therapy in Japan

OBJECTIVE

Helicobacter pylori treatment failure is thought to be due mainly to polymorphic cytochrome P450 2C19 (CPY2C19) genetic polymorphism, associated with proton pump inhibitor metabolism, and antimicrobial susceptibility. This report has ascertained which was more important, CPY2C19 polymorphism or antimicrobial susceptibility, when using 1-week lansoprazole-based or rabeprazole-based triple therapy in Japan.

DESIGN

An open, randomized, parallel group study.

SETTING

One hundred and forty-five subjects with H. pylori-positive gastritis or peptic ulcers were randomly assigned to receive 30 mg lansoprazole twice daily (LAC group), 10 mg rabeprazole twice daily (RAC20 group), or 20 mg rabeprazole twice daily (RAC40 group), with 1000 mg amoxicillin twice daily and 400 mg clarithromycin twice daily for 1 week. Antimicrobial resistance testing was performed by E-test. More than 4 weeks after completion of treatment, H. pylori status was assessed by 13C-urea breath test, histology, and culture.

RESULTS

Cure rates expressed as intention-to-treat and per-protocol analyses, respectively, were 79.6 and 83.0% with LAC, 85.4 and 89.1% with RAC20, and 83.3 and 88.9% with RAC40. In the case of clarithromycin-sensitive strains, the cure rates were more than 97%, regardless of CPY2C19 polymorphism. However, treatment succeeded in only one out of 16 clarithromycin-resistant strains.

CONCLUSIONS

The key to successful eradication of H. pylori, using lansoprazole or rabeprazole with clarithromycin and amoxicillin, is clarithromycin susceptibility, not CPY2C19 polymorphism.