Nitrofurans in the treatment of gastritis associated with Campylobacter pylori. The Gastrointestinal Physiology Working Group of Cayetano Heredia and The Johns Hopkins Universities

Helicobacter pylori: History and facts in Peru

Helicobacter pylori (H. pylori) is a cosmopolite bacteria and the main responsible for the high burden of gastric cancer in developing countries, such as Peru. In this review, we describe some historical facts in the H. Pylori discovery, the first researches of this bacterium in Peru, as well as its epidemiology, clinical characteristics, diagnosis, treatments, and outcomes. Our literature and review of real-life data suggest that several efforts should be conducted in our country to deal with antibiotic-resistance and lack of adherence to treatment in order to reduce our incidence of gastric cancer.

Development and validation of quality of life instruments for chronic diseases-Chronic gastritis version 2 (QLICD-CG V2.0)

Quality of life is an important outcome indicator to evaluate whether treatment is successful or not. Chronic gastritis leads to ongoing deterioration of subjectively perceived quality of life. There are several generic measures, but they are not developed particularly to assess chronic gastritis problems. The Quality of Life Instruments for Chronic Diseases-Chronic Gastritis (QLICD-CG V2.0) questionnaire is a 39-item, multi-dimensional, self-report instrument to assess chronic gastritis patients' perception of their health related quality of life in four domains. The instrument was developed in China. The current study aimed to evaluate the psychometric properties of the QLICD-CG V2.0. 194 patients with chronic gastritis were enrolled from 4 hospitals in China. The QLICD-CG V2.0 was administered to patients by trained research assistants. In addition, their demographic characteristics were also recorded. The psychometric testing included construct validity, convergent validity, discriminant validity, test-retest, and responsiveness. The results showed good internal consistency and acceptable floor and ceiling effects (Cronbach's alpha range from 0.80 to 0.93). CFA showed that the instrument structure has a reasonable fitness (RMSEA = 0.063, 95%CI = [0.057 0.079], CFI = 0.93, GFI = 0.95, SRMR = 0.028). The convergent validity was considered appropriate, with 38 of the 39 items correlated stronger with their assigned scale than a competing scale, except for GPS1. Known groups comparisons showed that the QLICD-CG V2.0 discriminated well between subgroups on the basis of gender, marriage status, and economy status, thus providing evidence of discriminative validity. Convergent validity testing revealed that the QLICD-CG V2.0 domain scores correlated significantly with SF-36 dimension scores, which ranged from 0.21 to 0.58. Test-retest coefficients were satisfactory. A majority of intraclass correlation coefficients were above 0.70, except the psychological domain (0.60) and the items of social support/security (0.61). Responsiveness was tested on 157 patients. Significant differences were found on all QLICD-CG V2.0 domains, between baseline responses and after a treatment, except for the items of appetite and sleep. Robust sensitivity to change was observed. The QLICD-CG V2.0 appears to be a valid and reliable instrument to measure QOL in chronic gastritis patients. Scores were reproducible.

WITHDRAWN: Eradication of Helicobacter pylori for non-ulcer dyspepsia

BACKGROUND

Helicobacter pylori (H pylori) is the main cause of peptic ulcer disease. The role of H pylori in non-ulcer dyspepsia is less clear.

OBJECTIVES

To determine the effect of H pylori eradication on dyspepsia symptoms in patients with non-ulcer dyspepsia.

SEARCH STRATEGY

Trials were identified through electronic searches of the Cochrane Controlled Trials Register (CCTR), MEDLINE, EMBASE, CINAHL and SIGLE, using appropriate subject headings and keywords, searching bibliographies of retrieved articles, and through contacts with experts in the fields of dyspepsia and with pharmaceutical companies.

SELECTION CRITERIA

All parallel group randomised controlled trials (RCTs) comparing drugs to eradicate H pylori with placebo or other drugs known not to eradicate H pylori for patients with non-ulcer dyspepsia.

DATA COLLECTION AND ANALYSIS

Data were collected on individual and global dyspeptic symptom scores, quality of life measures and adverse effects. Dyspepsia outcomes were dichotomised into minimal/resolved versus same/worse symptoms.

MAIN RESULTS

Twenty one randomised controlled trials were included in the systematic review. Eighteen trials compared antisecretory dual or triple therapy with placebo antibiotics +/- antisecretory therapy, and evaluated dyspepsia at 3-12 months. Seventeen of these trials gave results as dichotomous outcomes evaluating 3566 patients and there was no significant heterogeneity between the studies. There was a 10% relative risk reduction in the H pylori eradication group (95% CI = 6% to 14%) compared to placebo. The number needed to treat to cure one case of dyspepsia = 14 (95% CI = 10 to 25). A further three trials compared Bismuth based H pylori eradication with an alternative pharmacological agent. These trials were smaller and had a shorter follow-up but suggested H pylori eradication was more effective than either H2 receptor antagonists or sucralfate in treating non-ulcer dyspepsia.

AUTHORS' CONCLUSIONS

H pylori eradication therapy has a small but statistically significant effect in H pylori positive non-ulcer dyspepsia. An economic model suggests this modest benefit may still be cost-effective but more research is needed.

Nitrofuran-based regimens for the eradication of Helicobacter pylori infection

Several aspects of Helicobacter pylori eradication have been meta-analyzed; however, nitrofuran-based therapies constitute an exception. The aim of this study was the systematic review and meta-analysis of the effect of furazolidone- and nitrofurantoin-based regimens in the eradication of infection. Studies evaluating the effects of nitrofurans on H. pylori were identified from Medline, EMBASE, the Cochrane Controlled Trials Register and congress abstracts. The studies were classified into groups based on first-, second- and third-line regimens. The pooled eradication rates and combined odd ratios of the individual studies were calculated and compared with the published meta-analysis. The factors influencing the efficiency of the regimens were also analyzed. Side-effects of nitrofuran-based regimens were also analyzed. The pooled eradication rate of primary proton pump inhibitor-based regimens containing furazolidone was 76.3% (CI 67.8-84.2). The odds ratio for furazolidone-based regimens versus standard triple therapies was 2.34 (CI 0.76-3.92). Ranitidine bismuth citrate + furazolidone-based triple regimens were equally efficient (83.5%, CI 74.0-93.0, P = 0.06 versus triple therapies). Schedules including a H(2) antagonist + furazolidone + one other antibiotic achieved pooled eradication rates of 79.9% (CI 67.8-89.9, P = 0.04). Bismuth-based triple therapies achieved 84.5% (CI 72.6-93.0, P = 0.002). Primary quadruple regimens containing furazolidone were superior to triple therapies (83.4%, CI 69.7-92.3, P = 0.01). Second-line schedules containing furazolidone obtained eradication rates of 76.1% (CI 66.4-85.0, P = 0.28 versus primary regimens). Third-line 'rescue' therapies were efficient in 65.5% of the cases (CI 56.3-75.5, P = 0.0001). Side-effects of the regimens containing furazolidone were more frequent than in standard therapies (P = 0.02). The combined odds ratio of side-effects for furazolidone-based versus standard therapies was 0.74 (CI 0.32-1.98). The duration of treatment, but not the furazolidone dose, influenced the treatment outcome. Primary triple regimens containing furazolidone are slightly less efficient than the standard primary combinations; primary quadruple regimens were more efficient than triple therapies. Furazolidone is also efficient as a component of second-line or rescue therapies.

Eradication of Helicobacter pylori for non-ulcer dyspepsia

BACKGROUND

Helicobacter pylori (H pylori) is the main cause of peptic ulcer disease. The role of H pylori in non-ulcer dyspepsia is less clear.

OBJECTIVES

To determine the effect of H pylori eradication on dyspepsia symptoms in patients with non-ulcer dyspepsia.

SEARCH STRATEGY

Trials were identified through electronic searches of the Cochrane Controlled Trials Register (CCTR), MEDLINE, EMBASE, CINAHL and SIGLE, using appropriate subject headings and keywords, searching bibliographies of retrieved articles, and through contacts with experts in the fields of dyspepsia and with pharmaceutical companies.

SELECTION CRITERIA

All parallel group randomised controlled trials (RCTs) comparing drugs to eradicate H pylori with placebo or other drugs known not to eradicate H pylori for patients with non-ulcer dyspepsia.

DATA COLLECTION AND ANALYSIS

Data were collected on individual and global dyspeptic symptom scores, quality of life measures and adverse effects. Dyspepsia outcomes were dichotomised into minimal/resolved versus same/worse symptoms.

MAIN RESULTS

Twenty one randomised controlled trials were included in the systematic review. Eighteen trials compared antisecretory dual or triple therapy with placebo antibiotics +/- antisecretory therapy, and evaluated dyspepsia at 3-12 months. Seventeen of these trials gave results as dichotomous outcomes evaluating 3566 patients and there was no significant heterogeneity between the studies. There was a 10% relative risk reduction in the H pylori eradication group (95% CI = 6% to 14%) compared to placebo. The number needed to treat to cure one case of dyspepsia = 14 (95% CI = 10 to 25). A further three trials compared Bismuth based H pylori eradication with an alternative pharmacological agent. These trials were smaller and had a shorter follow-up but suggested H pylori eradication was more effective than either H2 receptor antagonists or sucralfate in treating non-ulcer dyspepsia.

AUTHORS' CONCLUSIONS

H pylori eradication therapy has a small but statistically significant effect in H pylori positive non-ulcer dyspepsia. An economic model suggests this modest benefit may still be cost-effective but more research is needed.

Eradication of Helicobacter pylori for non-ulcer dyspepsia

BACKGROUND

Helicobacter pylori (H pylori) is the main cause of peptic ulcer disease. The role of H pylori in non-ulcer dyspepsia is less clear.

OBJECTIVES

To determine the effect of H pylori eradication on dyspepsia symptoms in patients with non-ulcer dyspepsia.

SEARCH STRATEGY

Trials were identified through electronic searches of the Cochrane Controlled Trials Register (CCTR), MEDLINE, EMBASE, CINAHL and SIGLE, using appropriate subject headings and keywords, searching bibliographies of retrieved articles, and through contacts with experts in the fields of dyspepsia and with pharmaceutical companies. These searches were updated in October 2004.

SELECTION CRITERIA

All parallel group randomised controlled trials (RCTs) comparing drugs to eradicate H pylori with placebo or other drugs known not to eradicate H pylori for patients with non-ulcer dyspepsia.

DATA COLLECTION AND ANALYSIS

Data were collected on individual and global dyspeptic symptom scores, quality of life measures and adverse effects. Dyspepsia outcomes were dichotomised into minimal/resolved versus same/worse symptoms.

MAIN RESULTS

Seventeen randomised controlled trials were included in the systematic review. Fourteen trials compared antisecretory dual or triple therapy with placebo antibiotics +/- antisecretory therapy, and evaluated dyspepsia at 3-12 months. Thirteen of these trials gave results as dichotomous outcomes evaluating 3186 patients and there was no significant heterogeneity between the studies. There was a 8% relative risk reduction in the H pylori eradication group (95% CI = 3% to 12%) compared to placebo. The number needed to treat to cure one case of dyspepsia = 18 (95% CI = 12 to 48). A further three trials compared Bismuth based H pylori eradication with an alternative pharmacological agent. These trials were smaller and had a shorter follow-up but suggested H pylori eradication was more effective than either H2 receptor antagonists or sucralfate in treating non-ulcer dyspepsia.

AUTHORS' CONCLUSIONS

H pylori eradication therapy has a small but statistically significant effect in H pylori positive non-ulcer dyspepsia. An economic model suggests this modest benefit may still be cost-effective but more research is needed.

Dendroaspis natriuretic peptide in hepatic cirrhosis

OBJECTIVES

Dendroaspis natriuretic peptide (DNP) is a novel peptide that is structurally similar to atrial, brain, and C-type natriuretic peptides. Many natriuretic peptides are increased in hepatic cirrhosis, but the role of DNP in cirrhosis is unknown at present. The aim of the study was to investigate plasma levels of dendroaspis natriuretic-like immunoreactivity in cirrhosis.

METHODS

We measured plasma concentrations of DNP by radioimmunoassay methods in 12 cirrhotic patients without ascites and 44 cirrhotic patients with ascites, and compared these values with 20 age-matched healthy subjects. Renal function, plasma cGMP concentration, plasma renin activity, and plasma endothelin concentration were measured in each patient.

RESULTS

Patients without ascites had circulating levels of DNP similar to those of healthy subjects. By contrast, patients with ascites had increased circulating DNP levels compared to both patients without ascites and healthy subjects. In addition, circulating levels of DNP increased in relation to the severity of cirrhosis. Significant positive correlations were also found between DNP levels, endothelin concentrations, and plasma renin activity.

CONCLUSIONS

The results of this study indicate that plasma DNP is increased in cirrhotic patients with ascites.

Nitrofurantoin quadruple therapy for Helicobacter pylori infection: effect of metronidazole resistance

BACKGROUND

Antibiotic resistance has increasingly been recognized as the major cause of treatment failure for Helicobacter pylori infection. New therapies for patients with metronidazole- or clarithromycin-resistant H. pylori are needed.

AIM

To investigate the role of nitrofurantoin quadruple therapy for the treatment of H. pylori.

METHODS

Patients with confirmed H. pylori infection received nitrofurantoin (100 mg t.d.s.), omeprazole (20 mg b.d.), Pepto-Bismol (two tablets t.d.s.), and tetracycline (500 mg t.d.s.) for 14 days. Four or more weeks after the end of therapy, outcome was assessed by repeat endoscopy with histology and culture or urea breath testing.

RESULTS

Thirty patients were entered, including 25 men and five women; the mean age was 54.9 years. The most common diagnoses were duodenal ulcer (23%) and GERD (18%). The intention-to-treat cure rate was 70% (95% CI: 50.6-85%). Nitrofurantoin quadruple therapy was more effective with metronidazole-sensitive strains (88%; 15 out of 17) than with metronidazole-resistant strains (33%; three out of nine; P=0.008). Two of the treatment failures had pre-treatment isolates susceptible to metronidazole, which were resistant after therapy.

CONCLUSIONS

Because nitrofurantoin quadruple therapy performed inadequately in the presence of metronidazole resistance, we conclude that nitrofurantoin is unlikely to find clinical utility for the eradication of H. pylori.

Evaluation of nitrofurantoin combination therapy of metronidazole-sensitive and -resistant Helicobacter pylori infections in mice

The main objectives of this study were to determine whether the nitroreductase enzyme encoded by the rdxA gene of Helicobacter pylori was responsible for reductive activation of nitrofurantoin and whether a triple-therapy regimen with nitrofurantoin was able to eradicate metronidazole-sensitive and -resistant H. pylori infections from mice. The susceptibilities to nitrofurantoin of parent and isogenic rdxA mutant strains (three pairs), as well as a series of matched metronidazole-sensitive and -resistant strains isolated from mice (30) and patients (20), were assessed by agar dilution determination of the MIC. Groups of mice colonized with the metronidazole-sensitive H. pylori SS1 strain or a metronidazole-resistant rdxA SS1 mutant were treated with either metronidazole or nitrofurantoin as part of a triple-therapy regimen. One month after the completion of treatment the mice were sacrificed and their stomachs were cultured for H. pylori. The nitrofurantoin MICs for all strains tested were between 0.5 and 4.0 microg/ml. There was no significant difference between the susceptibility to nitrofurantoin of the parental strains and those of respective rdxA mutants or between those of matched metronidazole-sensitive and -resistant H. pylori isolates. The regimen with metronidazole eradicated infection from all eight SS1-infected mice and from one of eight mice inoculated with the rdxA mutant (P < or =0.001). The regimen with nitrofurantoin failed to eradicate infection from any of the six SS1-infected mice (P < or =0.001) and cleared infection from one of seven mice inoculated with the rdxA mutant. These results demonstrate that, despite the good in vitro activity of nitrofurantoin against H. pylori and the lack of cross-resistance between metronidazole and nitrofurantoin, eradication regimens involving nitrofurantoin are unable to eradicate either metronidazole-sensitive or -resistant H. pylori infections from mice.

A comprehensive review of the natural history of Helicobacter pylori infection in children

Across populations of children, Helicobacter pylori prevalence ranges from under 10% to over 80%. Low prevalence occurs in the U.S., Canada, and northern and western Europe; high prevalence occurs in India, Africa, Latin America, and eastern Europe. Risk factors include socioeconomic status, household crowding, ethnicity, migration from high prevalence regions, and infection status of family members. H. pylori infection is not associated with specific symptoms in children; however, it is consistently associated with antral gastritis, although its clinical significance is unclear. Duodenal ulcers associated with H. pylori are seldom seen in children under 10 years of age. H. pylori-infected children demonstrate a chronic, macrophagic, and monocytic inflammatory cell infiltrate and a lack of neutrophils, as compared with the response observed in adults. The effect of H. pylori infection on acid secretion in children remains poorly defined. The events that occur during H. pylori colonization in children should be studied more thoroughly and should include urease activity, motility, chemotaxis, adherence, and downregulation of the host response. The importance of virulence determinants described as relevant for disease during H. pylori infection has not been extensively studied in children. Highly sensitive and specific methods for the detection of H. pylori in children are needed, especially in younger pediatric populations in which colonization is in its early phases. Criteria for the use of eradication treatment in H. pylori-infected children need to be established. Multicenter pediatric studies should focus on the identification of risk factors, which can be used as prognostic indicators for the development of gastroduodenal disease later in life.

Cure of Helicobacter pylori infection does not improve symptoms in non-ulcer dyspepsia patients-a double-blind placebo-controlled study

BACKGROUND

It remains controversial whether the cure of H. pylori infection improves NUD symptoms.

AIM

To conduct a double-blind placebo-controlled single centre study with concealed allocation to investigate this question.

PATIENTS AND METHODS

Ninety NUD patients with H. pylori infection were randomly assigned to either the treatment group (50 patients) or placebo group (40 patients). The treatment group received omeprazole, amoxycillin, clarithromycin and the placebo group received omeprazole and placebos for 7 days. Symptoms were assessed every week for up to 12 weeks after completion of medication by a symptom questionnaire. Alteration of histological parameters for gastritis was also evaluated.

RESULTS

The infection was cured in 41 out of 48 patients in the treatment group and none in the placebo group. There was no significant difference in the mean symptom scores at any assessment point up to 12 weeks between the treatment and placebo groups. Regarding histological parameters, activity and inflammation, not atrophy or intestinal metaplasia, were significantly improved in the treatment group.

CONCLUSION

Although histological parameters were significantly improved in the treatment group, there was no significant improvement in symptoms of NUD in the treatment group compared to placebo.

Furazolidone versus metronidazole in quadruple therapy for eradication of Helicobacter pylori in duodenal ulcer disease

OBJECTIVE

Furazolidone, an old but cheap antibiotic, was shown to be a good alternative to metronidazole in triple therapy for Helicobacter pylori eradication in areas where metronidazole resistant bacteria are common, but randomized studies are lacking.

AIM

A randomized controlled trial to determine the efficacy and safety of furazolidone compared to metronidazole in classic quadruple therapy for eradication of H. pylori infection in duodenal ulcer patients.

METHODS

Patients with endoscopically proven duodenal ulcer and positive urease test were randomized to receive ranitidine 300 mg, amoxycillin 1000 mg and bismuth subcitrate 240 mg b.d, with either furazolidone 200 mg b.d (RABF), or metronidazole 500 mg b.d. (RABM) for 2 weeks. Compliance and side-effects were monitored and recorded by table diary. H. pylori eradication was assessed at least 4 weeks after the completion of therapy with 14C-urea breath test.

RESULTS

A total of 106 patients were enrolled and 101 (59 male, 42 female, mean age=40 +/- 11 years) completed the study. Endoscopic findings and demographic data were comparable in both groups. Intention-to-treat eradication rates were 75% and 55% (P=0.03) and per protocol eradication rates were 82 and 56% (P=0. 006) in the RABF and RABM groups, respectively. Side-effects were reported by 13 patients (27%) in the RABF group (one stopped treatment) compared to five patients (10%) in the RABM group (P=0. 04).

CONCLUSION

Quadruple therapy containing furazolidone, instead of metronidazole, results in a significantly higher H. pylori eradication rate in Iranian duodenal ulcer patients.

Furazolidone combination therapies for Helicobacter pylori infection in the United States

BACKGROUND

Antibiotic resistance has begun to impair the ability to cure Helicobacter pylori infection.

AIM

To evaluate furazolidone as a component of combination therapies for treatment of H. pylori infection in the United States.

METHODS

Patients with active H. pylori infection received furazolidone combination therapy for 14 days (furazolidone 100 mg and tetracycline 500 mg t.d.s.; omeprazole 20 mg o.d. in the morning and, depending on the pre-treatment antimicrobial susceptibility pattern, 500 mg of metronidazole or clarithromycin t.d.s.).

RESULTS

A total of 27 patients received the metronidazole containing combination (cure rate 100%) and seven received the clarithromycin combination (cure rate 86%). Overall the cure rates for intention-to-treat was 97% (95% CI: 85% to 100%). The single failure took the clarithromycin containing combination for only 2 days (per protocol cure rate = 100%). Side-effects were common and led to discontinuation of therapy in 26% of patients. An attempt to eliminate metronidazole and clarithromycin and use furazolidone, tetracycline, and lansoprazole b.d. produced an unsatisfactory cure rate of 72%.

CONCLUSION

Furazolidone combination therapy appears to be effective. Additional studies with different antimicrobial combinations and duration of therapy are warranted.

Role of anti-Helicobacter pylori treatment in H. pylori-positive and cytoprotective drugs in H. pylori-negative, non-ulcer dyspepsia: results of a randomized, double-blind, controlled trial in Asian Indians

BACKGROUND

The efficacy of anti-Helicobacter pylori treatment and cytoprotective drugs in H. pylori-positive and -negative non-ulcer dyspepsia (NUD), respectively, is debatable.

METHODS

In a randomized study, the efficacy of anti-H. pylori treatment versus sucralphate was tested in patients with NUD. One hundred and twelve patients with NUD, 62 positive and 50 negative for H. pylori were studied. Of 62 patients positive for H. pylori, 32 were treated with triple therapy (colloidal bismuth subcitrate, tetracycline and metronidazole) for 2 weeks and the remaining 30 were treated with sucralphate (1 g, q.i.d.) for 4 weeks. Of 50 patients negative for H. pylori, 25 each were treated with either sucralphate (1 g, q.i.d.) or ranitidine (150 mg, b.d.) for 4 weeks.

RESULTS

In patients with NUD and H. pylori infection, triple therapy eradicated H. pylori in 88% and was superior to sucralphate in producing symptom relief (81 vs 33%, P = 0.0003) and histological improvement in gastritis (73 vs 30%, P = 0.003). In the H. pylori-negative group, sucralphate was superior to ranitidine with regard to symptom relief (68 vs 36%, P = 0.04) and improvement in gastritis (44 vs 12%, P = 0.09). The symptomatic improvement persisted until 12 weeks after the start of treatment in triple therapy group only.

CONCLUSIONS

In patients with NUD associated with H. pylori, triple therapy was better than sucralphate in terms of symptomatic and histological improvement. However, sucralphate was superior to ranitidine in providing symptom relief in patients with H. pylori-negative NUD.

A systematic overview of the use of diary cards, quality-of-life questionnaires, and psychometric tests in treatment trials of Helicobacter pylori-positive and -negative non-ulcer dyspepsia

BACKGROUND

Our aim was to evaluate the use of diary cards, quality-of-life questionnaires, and psychometric tests in treatment trials of non-ulcer dyspepsia.

METHODS

Data sources were a Medline search (up to 1966) and a manual search of five gastrointestinal journals (up to 1980) for original, randomized, double-blind, placebo-controlled trials with at least 20 patients which evaluated treatment regimens for non-ulcer dyspepsia.

RESULTS

Of the 67 eligible studies, 31 used diary cards. Diary cards were used alone in 15 of the 31 studies (48%), whereas the others (52%) also used a physician assessment. The symptoms assessed by diary cards were epigastric pain (100%), nausea/vomiting (65%), heartburn (52%), belching (39%), regurgitation (29%), fullness (29%), and bloating (23%). Forty-five per cent also recorded antacid use. Severity of outcome measures was assessed by a visual analogue scale in 5 of the 31 studies (16%), Likert scales in 17 studies (55%), and unclear methods in 3 studies (10%). For statistical analysis daily averages of symptoms were used in 5 of the 31 studies (16%), weekly averages in 11 studies (35%), and 2-week intervals during the treatment period in the rest, with some studies using a combination (such as daily and weekly averages). Only 3 of the 31 studies (8%) checked for compliance with diary card data. None of the studies mention anything about missing data and how this was handled. One study evaluated quality of life questionnaires and one evaluated a psychometric test.

CONCLUSIONS

Non-ulcer dyspepsia treatment trials frequently use diary cards but need to be much clearer about how information was obtained and how it was used in the statistical analysis. Not much information is available to comment on the use of quality-of-life questionnaires or psychometric tests for evaluation of outcome measures.

Furazolidone-containing short-term triple therapies are effective in the treatment of Helicobacter pylori infection

BACKGROUND

A furazolidone-containing therapeutic regimen for Helicobacter pylori infection has attracted special interest in the face of a rising world-wide metronidazole resistant H. pylori, and the expense of currently used antimicrobial regimens.

AIM

To evaluate the efficacy of furazolidone-containing regimens in eradicating H. pylori.

METHODS

One-hundred and forty H. pylori positive patients with endoscopically confirmed duodenal ulcer or functional dyspepsia received one of four different regimens to eradicate H. pylori. In the first trial, the patients were randomly assigned to receive a 1-week course of furazolidone 100 mg b.d. and clarithromycin 250 mg b.d., with either tripotassium dicitrato bismuthate (TDB) 240 mg b.d. (FCB group) or lansoprazole 30 mg daily (FCL group). In the second trial, the patients were randomly assigned to receive a 1-week course of clarithromycin 250 mg b.d. and omeprazole 20 mg daily, with either furazolidone 100 mg b.d. (FCO group) or metronidazole 400 mg b.d. (MCO group). Endoscopy was repeated 4 weeks following completion of therapy with re-assessment of H. pylori status on gastric biopsies by histology and culture.

RESULTS

Four patients (1 in FCB, 1 in FCO and 2 in MCO groups) dropped out because they refused a follow-up endoscopy. Eradication rates of H. pylori on an intention-to-treat basis in the FCB, FCL, FCO and MCO groups were 91% (32/35, 95% CI: 82-99%), 91% (32/35, CI: 82-99%), 86% (30/35, CI: 74-97%) and 74% (26/35, CI: 60-89%) (all P > 0.05), respectively. Mild side-effects occurred in 15% of the 140 patients. In MCO group, the eradication rate in the patients infected with metronidazole-sensitive isolates of H. pylori was 86%, but dropped to 67% in those with metronidazole-resistance strains (P = 0.198).

CONCLUSION

One-week regimens containing furazolidone and clarithromycin in combination with TDB or a proton pump inhibitor fulfil the criteria for successful H. pylori therapy.

High cure rate of Helicobacter pylori infection using tripotassium dicitrato bismuthate, furazolidone and clarithromycin triple therapy for 1 week

BACKGROUND

When metronidazole is used in bismuth-based or proton pump inhibitor-based triple therapy, the cure rate of Helicobacter pylori is usually high. However, metronidazole-resistant H. pylori strains, which are increasing in frequency, are a major cause of failed H. pylori eradication.

AIM

To evaluate the efficacy of non-metronidazole containing bismuth-based triple therapy for H. pylori infection.

METHODS

One-hundred and eighty H. pylori-positive patients with endoscopically documented peptic ulcer disease or functional dyspepsia were randomly assigned to one of three 1-week regimens containing tripotassium dicitrato bismuthate (also called colloidal bismuth subcitrate) 240 mg b.d. and two antibiotics: furazolidone 100 mg b.d. plus clarithromycin 250 mg b.d. (Group A); or clarithromycin 250 mg b.d. plus amoxycillin 1000 mg b.d. (Group B); or furazolidone 100 mg b.d. plus josamycin 1000 mg b.d. (Group C). H. pylori status was assessed by rapid urease test, histology and culture of gastric biopsy specimens taken from both the antrum and corpus, both before and at least 4 weeks after completion of therapy.

RESULTS

Thirteen patients dropped out (3 in group A, 5 in group B and 5 in group C). Based on an intention-to-treat analysis, the eradication rates achieved in groups A, B and C were 88% (53/60), 58% (35/60) and 77% (46/60), respectively. These differences were significant between groups A and B (P < 0.001), as well as between groups B and C (P < 0.05). Side-effects occurred in 7 (12%) patients in group A, 3 (5%) in group B and 8 (13%) in group C, and were mild, with the exception of vomiting in one patient (group C) that resulted in withdrawal from the study.

CONCLUSION

One-week triple therapy, consisting of tripotassium dicitrato bismuthate, low-dose furazolidone and low-dose clarithromycin, achieves a high cure rate of H. pylori.

Differential normalization of mucosal interleukin-8 and interleukin-6 activity after Helicobacter pylori eradication

There is differential resolution of mucosal infiltration with neutrophils and mononuclear cells following successful Helicobacter pylori eradication. We investigated the effects of H. pylori eradication on mucosal interleukin-8 (IL-8) and IL-6 activity in relation to the resolution of H. pylori-associated gastritis. Eighty-one duodenal ulcer patients with H. pylori infection received dual- or triple-treatment eradication therapy, and mucosal biopsy specimens obtained at the initial and follow-up endoscopic examinations were cultured in vitro for 24 h. The levels of IL-8 and IL-6 were measured by enzyme-linked immunosorbent assays. In the 42 patients in whom H. pylori eradication failed, there was little change in the numbers of neutrophils and mononuclear cells infiltrating the mucosa and in IL-8 and IL-6 activity. In the 39 patients in whom H. pylori was eradicated, there was normalization both in the numbers of infiltrating neutrophils and in mucosal IL-8 activity, which was evident within 1 month following therapy. In contrast, there was a gradual resolution of mononuclear cell infiltration over a 6-month period, accompanied by a gradual normalization in IL-6 levels. Addition of H. pylori to cultures of mucosal tissues induced a significant increase in IL-8 activity in both uninfected control subjects and patients from whom H. pylori was eradicated. However, this introduction yielded a significant increase in IL-6 activity only in the latter group. This study indicates a dichotomy in the changes of mucosal IL-8 and IL-6 activity after H. pylori eradication. The rapid normalization of IL-8 after H. pylori eradication and the ability of H. pylori cells to stimulate IL-8 in control tissues indicate that IL-8 induction is a part of the innate (nonimmune) responses to this organism. In contrast, the results of experiments analyzing IL-6 activity in cultured mucosal tissues suggest that the gradual resolution of mucosal IL-6 activity and mononuclear infiltration after successful eradication observed in vivo may reflect gradually diminishing residual immune responses against H. pylori.

Gastrointestinal diseases in women

Gastrointestinal disorders are among the most common disorders for which women seek medical attention. Most gastrointestinal diseases in women are not inherently different from those that occur in men. There are several disorders, however, that occur more frequently or manifest themselves differently in women. This article reviews common gastrointestinal disorders affecting women. The pathophysiology, clinical manifestations, management, and gender-specific issues of gastroesophageal reflux disease, peptic ulcer disease, irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD) are discussed.

What role does Helicobacter pylori play in dyspepsia and nonulcer dyspepsia? Arguments for and against H. pylori being associated with dyspeptic symptoms

A major role for Helicobacter pylori gastritis in nonulcer dyspepsia (NUD) is controversial. Gastroduodenal dysfunction may be associated with H. pylori infection, but there is little evidence for a causal link with dyspepsia. Population-based studies with appropriate methodology have generally failed to confirm an association between H. pylori and NUD. Furthermore, no definite association between subgroups of NUD (ulcer-like, dysmotility-like, reflux-like, and nonspecific) and H. pylori has been identified however the subgroups have been defined, and no specific symptom pattern characterizes patients with H. pylori infection. Whether H. pylori-induced alterations of gastric physiology can explain NUD remains open to debate while we await the results of more specific experiments. Although acid secretion in response to gastrin-releasing peptide may be increased in a subset of NUD patients who are infected with H. pylori, uninfected patients with NUD have not been assessed and the results require confirmation. Most studies suggest no association between H. pylori and gastroduodenal motor or sensory dysfunction in NUD. Treatment trials have been unconvincing. The trials with bismuth therapy have not been adequately blinded. Furthermore, some studies suggest that H. pylori-negative patients with NUD may respond to bismuth treatment, although the results have not been uniform. Therapies aimed at curing H. pylori infection have produced mixed results, with small positive and negative trials. The trials that have used adequate outcome measures have more often than not been negative. Based on current evidence, H. pylori is not established to be of causal importance in NUD.

Furazolidone, amoxycillin, bismuth triple therapy for Helicobacter pylori infection

BACKGROUND

Metronidazole-resistant Helicobacter pylori are generally the rule in developing countries such as Colombia. Developing countries need an effective, simple and inexpensive non-metronidazole therapy for H. pylori infection.

AIM

To evaluate the combination of bismuth, furazolidone and amoxycillin for the treatment of H. pylori infection in Colombia.

METHODS

Thirty patients with histologically documented H. pylori infection received the combination of bismuth subcitrate 240 mg b.d., furzolidone 100 mg q.d.s. and amoxycillin 500 mg q.d.s. for 14 days. Four or more weeks after ending therapy patients were re-endoscoped and gastric biopsies were obtained and examined using the Genta stain. Each slide was scored for presence, absence and density of H. pylori, active and chronic inflammation, intestinal metaplasia, erosions and atrophy. Cure was defined as the absence of H. pylori.

RESULTS

All patients completed the course of therapy. Twenty-five patients were cured (86%, 95% CI: 65-94%). Mild, well-tolerated side-effects were reported by six patients (20%).

CONCLUSIONS

This combination of bismuth, furazolidone and amoxycillin fulfills the criteria for successful H. pylori therapy and appears particularly well suited for developing countries since it is simple, inexpensive and effective. Furazolidone-containing therapies may become especially useful in the face of a world-wide increase in H. pylori resistance to metronidazole and macrolides.

Low cure rate of Helicobacter pylori infection with omeprazole and furazolidone dual therapy for one week

BACKGROUND

Furazolidone is an inexpensive antibiotic that has considerable anti-Helicobacter pylori activity in vitro.

METHODS

Twenty-three patients with culture-proven H. pylori infection were treated for one week with a dual therapy containing omeprazole and furazolidone.

RESULTS

Eradication succeeded in 10 of the first 20 evaluable patients (50%; 95% CI: 27.2-72.8%). This percentage was regarded as too low, and the study was terminated. Side-effects were mild.

CONCLUSION

With the possible increase in resistance to metronidazole and clarithromycin world-wide, furazolidone may be useful alternative in the treatment of H. pylori infection. Dual therapy for one week, however, is not sufficient.

Eradication of Helicobacter pylori and long-term outcome of functional dyspepsia. A clinical endoscopic study

The aim of this study was to assess the effect of colloidal bismuth subcitrate (CBS) and metronidazole on Helicobacter pylori eradication and on the course of symptoms due to functional dyspepsia. Forty-one patients with functional dyspepsia were entered into the study and randomized to treatment with CBS (120 mg four times a day) for four weeks combined with metronidazole (250 mg four times a day) for one week (group A, N = 21) or matching placebo (group B, N = 20). The severity of gastritis and of bacterial colonization and the symptom score was assessed by endoscopy and clinical evaluation at baseline and after four, eight, and 24 weeks from the start of the treatment. With intent-to-treat analysis eradication was achieved in 16/25 (64%) patients in group A and in 6/24 (25%) in group B. At eight and 24 weeks the gastritis score was significantly lower only in those patients with eradication. No change was seen in patients in whom the bacteria was not eradicated. The symptom score at eight weeks was considerably lower both in patients with eradication and in those with infection. However, at 24 weeks a gradual decrease in the symptom score in patients with eradication and a worsening of symptoms in controls was observed. No differences were observed between patients with ulcerlike and those with dysmotility-like dyspepsia. The study confirms the need for a long observation period after antibacterial treatment in patients with functional dyspepsia and suggests that Helicobacter pylori-eradicating treatment improves the course of this functional syndrome.

Activity of amoxicillin, metronidazole, bismuth salicylate and six aminoglycosides against Helicobacter pylori

The in vitro activity of metronidazole, amoxicillin, bismuth salicylate and some aminoglycosides, such as ribostamycin, gentamicin, amikacin, tobramycin, streptomycin and netilmicin was evaluated against 60 clinical isolates of Helicobacter pylori using the agar dilution technique. All 60 strains were susceptible to amoxicillin, with minimum concentrations able to inhibit 50% (MIC 50) and 90% (MIC 90) of strains equal to 0.031 microgram/ml and 0.25 microgram/ml, respectively. Of the aminoglycosides, ribostamycin, streptomycin and amikacin had a little lower activity (MIC 50 of 2 micrograms/ml, MIC 90 of 4-8 micrograms/ml) than gentamicin, tobramycin and netilmicin, with MIC 50s of 0.125 microgram/ml and MIC 90s of 0.25 microgram/ml. Metronidazole was effective against the majority of the strains, but we found ten resistant strains. Finally, bismuth salicylate showed only slight antibacterial activity.

Pooled analysis of anti-Helicobacter pylori treatment regimens

BACKGROUND

The human pathogen Helicobacter pylori and its association with peptic ulcer has dramatically changed the therapeutic approach to patients with this disease. Successful treatment of the infection has consistently been shown to prevent ulcer recurrence. Published data on therapeutic options are sometimes confusing since only few studies have similar design, drug combinations, dosage, dosing, formulation, patient material, and size. A formal meta-analysis is therefore of limited value.

METHOD

Data on anti-H. pylori therapies from a large number of publications are pooled into a few groups based on the combination of drugs, regardless of dosage, duration, etc., of the therapy. A mean success rate is calculated for all studies with subanalysis with regard to study design, size, doses and duration.

RESULTS

Triple combinations are needed to achieve a success rate of more than 80%. Bismuth/tetracycline based triple therapy gives 82% success rate (range 43-100%) compared to 85% and 87% success rate (range 72-100% and 43-100%) achieved with omeprazole/clarithromycin based triples respectively.

CONCLUSION

Omeprazole/clarithromycin based triple regimens are the most effective anti-H. pylori therapeutic strategies, slightly superior to bismuth triple regimens.

Long-term colonization with single and multiple strains of Helicobacter pylori assessed by DNA fingerprinting

The gastric pathogen Helicobacter pylori establishes long-term chronic infections that can lead to gastritis, peptic ulcers, and cancer. The species is so diverse that distinctly different strains are generally recovered from each patient. To better understand the dynamics of long-term carriage, we characterized H. pylori isolates from initial and follow-up biopsy specimens from a patient population at high risk of H. pylori infection and gastric cancer. Eighty-five isolates were obtained from 23 patients and were analyzed by genomic restriction enzyme analysis, arbitrarily primed PCR fingerprinting, (random amplified polymorphic DNA analysis), and/or restriction of specific PCR-amplified genes (restriction fragment length polymorphism analysis). A single strain was found in sequential biopsy specimens from 12 of 15 patients (80%) receiving sucralfate. In the remaining three patients treated with sucralfate, two strains were identified in two patients and three strains were identified in the third patient. In contrast, a single strain was found in sequential biopsy specimens from only three of eight patients (37%) receiving bismuth, metronidazole, and nitrofurantoin. Two strains were identified in five other patients receiving bismuth-antibiotic (63%). Immunoglobulin G antibodies to H. pylori were present in the sera of all patients. Thus, H. pylori colonization can persist for long periods (up to at least 4 years), despite high titers of immunoglobulin G antibodies in serum. Resistance to metronidazole was noted in some strains before and/or after treatment, but all strains remained susceptible to amoxicillin, tetracycline, and nitrofurantoin. We conclude that H. pylori genotypes, as measured by several sensitive DNA fingerprinting methods, can remain stable for years in vivo, despite the acquisition or loss of drug resistance, circulating antibody, or exposure to antibiotics or sucralfate.

A critique of therapeutic trials in Helicobacter pylori-positive functional dyspepsia

BACKGROUND/AIMS

Approximately 50% of patients with functional dyspepsia have Helicobacter pylori infection; it remains controversial whether this infection causes chronic symptoms, but rigorously conducted therapeutic trials should establish whether H. pylori plays a role in functional dyspepsia. The aim here was to determine whether the trials published over the past 10 years were methodologically adequate to establish a role for this infection in functional dyspepsia.

METHODS

A broad-based Medline search to identify all treatment trials published between 1984 and 1993 was performed. All functional dyspepsia trials were systematically analyzed for potential design strengths and weaknesses.

RESULTS

Sixteen trials were included; 8 reported that anti-H. pylori therapy was efficacious and 8 failed to detect a statistically significant benefit. However, in all studies one or more serious methodological weakness was identified, including nonrandomized, non-placebo-controlled designs, lack of maintenance of blindness, application of inadequate outcome measures, failure to eradicate infection and follow up patients after therapy, and inadequate study power.

CONCLUSIONS

There is a pressing need for well-designed trials in H. pylori-positive dyspepsia, and practical suggestions are provided based on a review of the published literature.

Efficacy and side effects of a triple drug regimen for the eradication of Helicobacter pylori

One hundred consecutive patients with Helicobacter pylori infection, as proven by culture, were treated with 120 mg colloidal bismuth subcitrate (CBS) four times daily, 250 mg tetracycline four times daily, and 250 mg metronidazole four times daily during 15 days. The patients were amply instructed in how to take the medicine and strongly urged to complete the prescribed course. In 66 of the 100 patients pretreatment metronidazole susceptibility was determined. Endoscopy was performed 3 months after cessation of treatment to check for H. pylori eradication by culture, urease testing, and histology. Side effects of the treatment were registered and classified into five groups on the basis of severity. Eradication was achieved in 93 of 100 patients (93%), in 61 of 62 patients with a metronidazole-sensitive strain (98.4%), and in 2 of 4 patients with a metronidazole-resistant strain (50%). Eighty-two per cent of the patients experienced no or just minor side effects; 15% had moderate side effects, and just 3% had severe side effects. Non-ulcer dyspepsia patients reported significantly more side effects than patients with peptic ulcer disease. With proper patient instruction, this treatment regimen is well tolerated and very effective for the eradication of metronidazole-sensitive H. pylori strains.

Functional dyspepsia. Current treatment recommendations

Symptoms of functional dyspepsia are frequent; the prevalence of dyspepsia (defined as pain or discomfort centred in the upper abdomen) in the general population approaches 25%. By definition, patients with functional dyspepsia do not have a structural or biochemical explanation for their symptoms. Disorders of function (e.g. delayed gastric emptying) are detectable in a proportion of patients but remain poorly understood. Nevertheless, the current rationale for drug treatment is based on altering pathophysiological mechanisms which are believed to be associated with the development of symptoms. Although the placebo response rates approach 60%, prokinetics, acid-suppressing agents and bismuth-containing compounds have been shown to be significantly better than placebo in reducing symptoms. Antacids are widely used, but no controlled study has been able to demonstrate a significant benefit over placebo. The efficacy of sucralfate is uncertain. Rational guidelines on which drug should be used for a given patient are lacking, although approaches based on symptom profiles have been proposed; the duration of treatment needed to achieve long-lasting relief of symptoms is also poorly defined. Identifying optimal treatment for the individual patient, therefore, continues to be largely a trial and error process. Further research efforts are needed to elucidate the pathophysiological basis of functional dyspepsia so that specific therapy can be tailored to underlying pathophysiological disturbances.

Can severity of symptoms be used as an outcome measure in trials of non-ulcer dyspepsia and Helicobacter pylori associated gastritis?

Most trials of non-ulcer dyspepsia (NUD) and Helicobacter pylori associated gastritis (HPAG) have not used validated methods of measuring symptoms. Three attributes are necessary for use of symptom severity scoring systems as outcome measures in clinical trials: reproducibility, responsiveness to change and validity compared to corroborating measures. The objective of this study was to establish that selected gastrointestinal symptoms recorded as a series of 5-point Likert Scales meet the 3 criteria for use as outcome measures in clinical trials. Patients with NUD (Helicobacter pylori-negative) and HPAG were studied. A preliminary assessment of 24 patients was used to select the 8 most frequently occurring and most severe symptoms. These symptoms were then scored in a further 55 patients to assess their utility as outcome measures. Observations were made at 3 time points, enrollment (T1), after 1 week with no intervention (T2) and after 4 weeks of therapy for either disease (T3). The study took place in a university hospital outpatient gastroenterology service. Symptom scores were reproducible before treatment (symptom scores at T1 and T2 were correlated), responsive (symptom scores changed after treatment between T2 and T3) and valid (symptom score changes corresponded to changes in general health status). Scoring of gastrointestinal symptom severity using 5-point Likert Scales satisfies the 3 criteria for use as outcome measures in clinical trials of NUD and HPAG.

A systematic overview (meta-analysis) of outcome measures in Helicobacter pylori gastritis trials and functional dyspepsia

STUDY AIM

To critically appraise the use of outcome measures in treatment trials of Helicobacter pylori positive non-ulcer dyspepsia patients.

METHODS

Meta-analysis of published randomized placebo-controlled clinical trials.

RESULTS

Significant methodological problems were detected in all seven retrieved studies. There is marked variation in measurement of: symptoms, scales used to assess severity of dyspepsia, use of global assessments and methods used to determine whether a change occurred in symptom severity.

CONCLUSION

Much more attention needs to be paid to outcome measures in non-ulcer dyspepsia trials and consensus on this should be reached by investigators in this area.

Plasma levels of brain natriuretic peptide in patients with cirrhosis

Plasma levels of brain natriuretic peptide, a recently identified cardiac hormone with natriuretic activity, were measured in 11 healthy subjects, 13 cirrhotic patients without ascites, 18 nonazotemic cirrhotic patients with ascites and 6 patients with cirrhosis, ascites and functional kidney failure. Plasma levels of brain natriuretic peptide were similar in healthy subjects and cirrhotic patients without ascites (5.56 +/- 0.65 and 7.66 +/- 0.68 fmol/ml, respectively). In contrast, cirrhotic patients with ascites, with and without functional kidney failure, had significantly higher plasma concentrations of brain natriuretic peptide (19.56 +/- 1.37 and 16.00 +/- 1.91 fmol/ml, respectively) than did healthy subjects and patients without ascites (p less than 0.01); no significant difference was found between the two groups of cirrhotic patients with ascites with respect to this parameter. In the whole group of cirrhotic patients included in the study, brain natriuretic peptide level was directly correlated with the degree of impairment of liver and kidney function, plasma renin activity and plasma levels of aldosterone and atrial natriuretic peptide. The results of this study indicate that brain natriuretic peptide is increased in cirrhotic patients with ascites and suggest that sodium retention in cirrhosis is not due to deficiency of this novel cardiac hormone.

Review article: the treatment of Helicobacter pylori infection

The discovery of Helicobacter pylori has stimulated great interest in its role in gastritis, non-ulcer dyspepsia and peptic ulceration. Treatment regimens to eradicate this organism from gastric mucosa have also received considerable attention. Current recommendations limit the use of triple drug combinations only to specific patient groups.

Pathologic changes of gastric mucosa colonized by Helicobacter pylori

One hundred eighty-nine consecutive gastric biopsies showing colonization by Helicobacter pylori (HP) were studied. Epigastric pain and bleeding were the clinical presentations in 167 cases (88.4%). Major endoscopic findings were gastritis (n = 72, 38.1%) and ulceration (n = 101, 53.4%). Duodenal ulcer was associated with 32 (44.4%) and 29 (28.7%) cases of gastritis and gastric ulcer, respectively. Histologically, the HP-colonized gastric epithelium showed characteristic degenerative changes that were topographically related to the bacteria but unrelated to the inflammatory infiltrate. Disintegration and loss of apical mucus with formation of epithelial pits was seen in nearly all cases. Other changes included microerosion, conventional erosion, and frank ulceration. Only the disintegration of apical mucus, epithelial pit, and microerosion were specific for HP colonization. These conditions were absent in areas not colonized by HP and in 79 consecutive HP-negative gastric biopsies seen during the same study period. The epithelial degenerative changes in HP-colonized gastric mucosa are easy to recognize in routine hematoxylin-eosin-stained sections and they could serve as histologic guides to the localization of the bacteria. It is proposed that HP-colonized gastric mucosa is a distinct pathologic entity with a pathologic spectrum ranging from active chronic gastritis to erosion and frank ulcer. Damage to the mucin-containing portion of the gastric epithelial cells appears to be the basic cytopathologic effect of HP on the gastric mucosa. As effective specific treatment for HP infection is available, identification of HP colonization in gastric biopsies should be attempted in all cases of gastritis and gastric ulcer.

Atrial natriuretic peptide in portal vein-ligated rats: alterations in cardiac production, plasma level and glomerular receptor density and affinity

The atrial natriuretic peptide hormonal system is altered to a variable degree in patients with cirrhosis. Portal pressure and portal-systemic shunting are also varied in cirrhosis. We used a portal vein-ligated rat model with predictable portal hypertension to study the effects of portal hypertension alone on the atrial natriuretic peptide hormonal system. Sham-operated rats were used as controls. Mean portal pressure was significantly increased in portal vein-ligated rats (portal vein-ligated rats, 21.7 +/- 0.74 cm H2O; sham-operated rats, 13.7 +/- 0.47 cm H2O; p less than 0.0001). Plasma atrial natriuretic peptide decreased 50% in the portal vein-ligated rats (p less than 0.0001). Atrial natriuretic peptide messenger RNA level was decreased by 40% to 60% in the left and right atria and in the ventricles of portal vein-ligated rats (p less than 0.05 for each chamber). Only one class of glomerular binding site was identified by competitive binding studies. The atrial natriuretic peptide glomerular receptor density increased in the portal vein-ligated rats (portal vein-ligated rats, 1,660 +/- 393; sham-operated 725 +/- 147 fmol/mg protein, p less than 0.02), whereas affinity decreased (portal vein-ligated, 1.69 +/- 0.49; sham-operated, 0.55 +/- 0.12 nmol/L, p less than 0.02). No difference was seen in the amount of cyclic GMP generated by atrial natriuretic peptide stimulation in isolated glomeruli from portal vein-ligated and sham-operated rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Surface proteins from Helicobacter pylori exhibit chemotactic activity for human leukocytes and are present in gastric mucosa

The mechanism by which Helicobacter pylori, a noninvasive bacterium, initiates chronic antral gastritis in humans is unknown. We now show that H. pylori releases products with chemotactic activity for monocytes and neutrophils. This chemotactic activity was inhibited by antisera to either H. pylori whole bacteria or H. pylori-derived urease. Moreover, surface proteins extracted from H. pylori and purified H. pylori urease (a major component of the surface proteins) exhibited dose-dependent, antibody-inhibitable chemotactic activity. In addition, a synthetic 20-amino acid peptide from the NH2-terminal portion of the 61-kD subunit, but not the 30-kD subunit, of urease exhibited chemotactic activity for monocytes and neutrophils, localizing the chemotactic activity, at least in part, to the NH2 terminus of the 61-kD subunit of urease. The ability of leukocytes to chemotax to H. pylori surface proteins despite formyl-methionyl-leucyl-phenylalanine (FMLP) receptor saturation, selective inhibition of FMLP-mediated chemotaxis, or preincubation of the surface proteins with antiserum to FMLP indicated that the chemotaxis was not FMLP mediated. Finally, we identified H. pylori surface proteins and urease in the lamina propria of gastric antra from patients with H. pylori-associated gastritis but not from uninfected subjects. These findings suggest that H. pylori gastritis is initiated by mucosal absorption of urease, which expresses chemotactic activity for leukocytes by a mechanism not involving N-formylated oligopeptides.

Factors influencing the eradication of Helicobacter pylori with triple therapy

Helicobacter pylori infection has been associated with gastritis, duodenal ulcer, gastric ulcer, and the epidemic form of gastric carcinoma. Eradication of H. pylori infection has proven to be difficult. Recently, combinations of antimicrobial drugs have been shown to eradicate greater than 50% of infections; however, the results have proven variable, and the factors influencing effectiveness of therapy are unclear. In the present study, the effectiveness of a triple therapy for eradication of H. pylori infection was evaluated. Triple therapy consisted of 2 g tetracycline, 750 mg metronidazole, and five or eight tablets of bismuth subsalicylate daily in 93 patients (70 with duodenal ulcer, 17 with gastric ulcer, and 6 with simple H. pylori gastritis). Combinations of a sensitive urea breath test, serology, culture, and histology were used to confirm the presence of infection, eradication, or relapse. Eradication was defined as inability to show H. pylori greater than or equal to 1 month after ending therapy. The overall eradication rate was 87%. The factors evaluated for their effect on predicting eradication included age, gender, type of disease, duration of therapy, amount of bismuth subsalicylate [five or eight Pepto-Bismol tablets daily (Procter & Gamble, Cincinnati, OH)], and compliance with the prescribed medications. Stepwise regression showed that compliance was the most important factor predicting success; the success rate was 96% for patients who took greater than 60% of the prescribed medications and 69% for patients who took less. For those taking greater than 60% of the prescribed therapy, the eradication rates were similar (a) for patients receiving therapy for 14 days or when tetracycline and bismuth subsalicylate were taken for an additional 14 days; (b) for patients with duodenal ulcer, gastric ulcer, and simple H. pylori gastritis; and (c) whether five or eight bismuth subsalicylate tablets were taken. It is concluded that triple therapy is effective for eradication of H. pylori and that future studies need to take compliance into account for comparisons between regimens.

Role of metronidazole resistance in therapy of Helicobacter pylori infections

Susceptibility to metronidazole was determined by disk diffusion tests for 559 strains of Helicobacter pylori isolated from patients. The overall metronidazole resistance was 26%. In males metronidazole-resistant strains made 18% of all H. pylori strains, and in females the corresponding figure was 40% (P less than 0.001). MICs of metronidazole were determined for H. pylori strains from 86 patients undertaking triple therapy, i.e., treatment with colloidal bismuth subcitrate, amoxicillin, and metronidazole. Of the nonresponders who remained culture positive despite the therapy, 69% had strains with metronidazole MICs of greater than or equal to 32 micrograms/ml before the therapy, and all nonresponders had metronidazole-resistant strains after the therapy. Metronidazole resistance was, however, also found in 27% of responders before therapy. To find whether the MICs of metronidazole for H. pylori strains remained constant for longer periods, consecutive isolates sampled several years apart from the same patients were tested in parallel and no changes in the MICs were found. H. pylori was successfully eradicated by the triple therapy from 91% of patients with metronidazole-susceptible pretreatment strains and from 63% of patients with metronidazole-resistant strains before the therapy (P less than 0.01). Although resistance to metronidazole has a significant role in treatment failures in H. pylori infections, high eradication rates can be achieved with the use of the present triple therapy even in populations with a high overall metronidazole resistance rate.

Helicobacter pylori infection and non-ulcer dyspepsia: the effect of treatment with colloidal bismuth subcitrate

A study was undertaken to determine the role of Helicobacter pylori in non-ulcer dyspepsia (NUD) and to determine the efficacy of colloidal bismuth subcitrate (CBS) in the treatment of NUD. Seventy-one patients were randomly allocated (double blind) to CBS or placebo, two tablets twice daily for 4 weeks. The severity of dyspepsia was scored and endoscopies performed before and after treatment, and antral biopsy specimens were taken for bacteriologic and histologic examination. Forty patients had H. pylori infection, and all had changes of chronic active gastritis. H. pylori was cleared from 17 to 21 patients (81%) treated with CBS, whereas none of the 19 patients treated with placebo cleared the bacteria. Improvement in histology was noted in 15 of 21 patients (71.4%) treated with CBS, whereas no improvement was noted in any of the placebo controls. Thirty-one patients were negative for H. pylori. All had either normal gastric histology or minor degrees of inflammation. Seventeen of these patients received CBS, and 14 received placebo. All groups reported improvement in the symptom score; however, the H. pylori-positive, CBS-treated group recorded a significantly higher improvement than the other groups (p less than 0.001). Relapse of H. pylori infection after initial clearance of the bacteria was high. Twelve of 16 patients evaluated relapsed 1 month after withdrawal of CBS.

Disappearance of gastritis after eradication of Helicobacter pylori. A morphometric study

Helicobacter pylori infection is strongly associated with and is considered a common cause of gastritis. To study the relationship between H. pylori and gastritis, we examined whether a reduction occurs in acute granulocytic and chronic mononuclear inflammation of gastric mucosa after eradication therapy. The examination is based on morphometric counting and on semiquantitative estimation of the density of the inflammatory cells in endoscopic biopsy specimens from antrum and corpus. The series consisted of 23 consecutive outpatients with H. pylori-associated gastritis who received a 2-week course of triple therapy with colloidal bismuth subcitrate, amoxicillin, and metronidazole and who underwent an endoscopic follow-up for 6 weeks, 6 months (23 patients), and 12 months (21 patients). The eradication was successful in 20 patients ('responders'), who also remained H. pylori-free for 6 months, and in 18 examined patients for 12 months but was unsuccessful in 3 patients ('non-responders'). Both acute and chronic inflammation decreased significantly in intensity in responders in the follow-up. The acute inflammation had already disappeared at a 6-week control. The reduction in chronic inflammation was slower and occurred gradually within the study. At the 12-month follow-up, the corpus mucosa was interpreted as normal in all 18 patients studied, and the antral mucosa was interpreted as normal in 10 (56%) patients. No significant reduction in intensity of gastritis was found in the 3 non-responders or the 23 matched, untreated controls. We conclude that the eradication of H. pylori results in a disappearance of both acute and chronic gastritis. This supports the view that H. pylori plays a causal role in the pathogenesis of chronic gastritis.