[Effectiveness of empirical Helicobacter pylori eradication therapy with furazolidone in Russia: results from the European Registry on Helicobacter pylori Management (Hp-EuReg)]

BACKGROUND

First-line therapy does not always provide a high level of Helicobacter pylori eradication due to the increase of H. pylori resistance to antibiotics; therefore, it remains necessary to identify the most effective rescue treatments. The purpose of this study was to evaluate the efficacy and safety of empirical H. pylori furazolidone-containing regimens.

MATERIALS AND METHODS

Adult H. pylori infected patients empirically treated with furazolidone-containing eradication regimens were registered in an international, prospective, multicenter non-intervention European registry on H. pylori management (Hp-EuReg). Data were collected at AEG-REDCap e-CRF from 2013 to 2021 and the quality was reviewed. Modified intention-to-treat (mITT) effectiveness analyses were performed.

RESULTS

Overall 106 patients received empirical furazolidone-containing therapy in Russia. Furazolidone was prescribed in a sequential scheme along with amoxicillin, clarithromycin and a proton pump inhibitor in 68 (64%) cases, triple regimens were prescribed in 28 (26%) patients and quadruple regimens in 10 (9.4%). Treatment duration of 7 days was assigned to 2 (1.9%) patients, 10-day eradication therapy in case of 80 (75%) and 14 days - in 24 (23%) patients. Furazolidone was mainly used in first- (79%) and second-line (21%) regimens. The methods used to diagnose H. pylori infection were: histology (81%), stool antigen test (64%), ¹³C-urea breath test (6.6%), and rapid urease test (1.9%). The mITT effectiveness of sequential therapy was 100%; 93% with the triple therapy and 75.5% with quadruple therapy. Compliance was reported in 98% of cases. Adverse events were revealed in 5.7% of patients, mostly nausea (3.8%). No serious adverse events were reported.

CONCLUSION

Furazolidone containing eradication regimens appear to be an effective and safe empirical therapy in Russia.

[European Registry on the management of Helicobacter pylori infection: features of diagnosis and treatment in Kazan]

BACKGROUND

As part of an observational multicenter prospective study European Registry on the management of Helicobacter pylori infection, conducted on the initiative of the European H. pylori and Microbiota Study Group, the compliance of clinical practice in the management of patients with Helicobacter pylori infection in Kazan with clinical guidelines was assessed.

MATERIALS AND METHODS

The data of 437 patients included into the register by clinical sites in Kazan in 20132019 were analyzed. The methods used for the initial diagnosis of H. pylori infection and eradication control were evaluated. The frequency of various eradication therapy regimens prescription was analyzed in 379 cases. Data regarding the effectiveness of eradication therapy was analyzed in 173 patients.

RESULTS

The rapid urease test (44.2% of cases) and cytology/histology (60% of cases) were most often used for the initial diagnosis of H. pylori infection; however non-invasive methods such as 13C-urea breath (9.2%), serology (6.2%), H. pylori stool antigen test (2.3%) were less common. In 21.7% of patients two methods of H. pylori detection were used for primary diagnosis. The control test to evaluate the effectiveness of eradication therapy at the recommended timepoint was performed in 46.2% of patients. 13C-urea breath test (31.7%), stool PCR/stool antigen test (28.7%), rapid urease test (22.3%), cytology/histology (26.2% of cases) prevailed in the assessment of eradication rate. Standard triple therapy, including proton pump inhibitor, clarithromycin and amoxicillin was most commonly prescribed as first-line therapy (64.6% of cases). The duration of eradication therapy was 14 days in the majority of cases with pantoprazole as the most common proton pump inhibitor in standard triple therapy regimens (84.8%). The efficacy of 14-day standard triple therapy (mITT) was 87.0%.

CONCLUSION

The results indicate a high frequency of non-invasive methods use for assessing the effectiveness of eradication therapy; however, the overall rate of eradication efficacy assessment is low, limiting the possibility of analyzing the eradication results. The effectiveness of the most common 14-day standard triple first-line therapy in Kazan doesnt reach the recommended 90% eradication level. This could be explained by high rate of pantoprazole use, which is not an optimal proton pump inhibitor in eradication therapy regimens.

European Registry on the management of Helicobacter pylori infection (Hp-EuReg): analysis of 2360 patients receiving first-line therapy in Russia

AIM

European Registry on the management of Helicobacter pylori infection («Hp-EuReg») - a multicenter prospective observational study initiated by the European Helicobacter and Microbiota Study Group, conducted in 27 European countries in order to evaluate the real clinical practice of diagnosis and treatment of H. pylori and its comparison with international recommendations.

MATERIALS AND METHODS

The analysis of 2360 patients entered in the register by the Russian centres of «Hp-EuReg» in 2013-2017, who were underwent 1st line eradication therapy.

RESULTS

The most common methods of primary diagnosis of H. pylori are histological (37.7%), rapid urease test (29.2%) and serology (29.7%). The duration of eradication therapy in 9.4% of cases was 7 days, in 65.3% - 10 days, and in 25.3% - 14 days. To control the effec- tiveness of treatment, H. pylori antigen in feces (31.3%), urea breath test (23.4%) and histological method (23.3%) were used. In 3.6% cases was used serology by mistake. In 17.3% of patients control was not carried out. The effectiveness of triple therapy with a PPI, amoxicillin, clar- ithromycin (per protocol) was 67.6%, with 7-day course, 81.1% at 10-day and 86.7% at 14-day course. Eradication rate of triple therapy with addition of bismuth (per protocol) reached 90,6% in the group receiving 10-day scheme and 93.6% in the group receiving the 14-day treatment.

CONCLUSION

Significant deviations of clinical practice from expert recommendations, most pronounced at the stage of monitoring the effectiveness of therapy, were noted. The suboptimal efficacy of triple therapy is shown.

[European registry Helicobacter pylori (Hp-EuReg): how has clinical practice changed in Russia from 2013 to 2018 years]

The multicenter prospective observational study initiated by the European Helicobacter and Microbiota Study Group (EHMSG) is conducted in 27 countries in Europe. The data from the Russian part of the European registry for the management of Helicobacter pylori infection (European Registry on the management of Helicobacter pylori infection, protocol: "Hp-EuReg") allows us to analyze the real clinical practice of diagnosis and treatment of H. pylori and compare it with international recommendations.

MATERIALS AND METHODS

A comparative analysis of the data entered in the register by the Russian research centers "Hp-EuReg", in the period from 2013 to 2018, was conducted.

RESULTS AND DISCUSSION

Invasive diagnostic methods prevail for the primary diagnosis of H. pylori [histology - 20.3% (in 2013 year) - 43.9% (in 2018 year), rapid urease test - 31.7% and 47.8% respectively]. The most popular mode of eradication therapy is a 10-day triple therapy (62.8-76.2%), the effectiveness of which does not exceed 79% (per protocol). Invasive tests (histology) are the leading method for control the effectiveness of therapy, however, there is a tendency towards a wider use of non-invasive methods (H. pylori stool antigen - from 17% in 2013 to 29.3% in 2018 and urea breath test from 6.9 to 18.3%, respectively). Serological test to control the effectiveness of eradication is still used from 8.2% (2013) to 6.1% (2018). Eradication therapy was not performed in 28% of patients throughout the entire observation period.

CONCLUSION

In Russia, despite approved domestic and international recommendations, deviations in clinical practice persist, both during eradication therapy and in monitoring the effectiveness of eradication therapy.

Management of Helicobacter pylori infection-the Maastricht V/Florence Consensus Report

Important progress has been made in the management of Helicobacter pylori infection and in this fifth edition of the Maastricht Consensus Report, key aspects related to the clinical role of H. pylori were re-evaluated in 2015. In the Maastricht V/Florence Consensus Conference, 43 experts from 24 countries examined new data related to H. pylori in five subdivided workshops: (1) Indications/Associations, (2) Diagnosis, (3) Treatment, (4) Prevention/Public Health, (5) H. pylori and the Gastric Microbiota. The results of the individual workshops were presented to a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in the various clinical scenarios.

Helicobacter pylori infection assessed by ELISA and by immunoblot and noncardia gastric cancer risk in a prospective study: the Eurgast-EPIC project

BACKGROUND

In epidemiological studies, Helicobacter pylori infection is usually detected by enzyme-linked immunosorbent assay (ELISA). However, infection can spontaneously clear from the mucosa during the progression of atrophy and could lead to substantial under-detection of infection and underestimation of its effect on gastric cancer (GC) risk. Antibodies detected by western blot are known to persist longer after the loss of the infection.

METHODS

In a nested case-control study from the Eurogast-EPIC cohort, including 88 noncardia GC cases and 338 controls, we assessed the association between noncardia GC and H. pylori infection comparing antibodies detected by western blot (HELICOBLOT2.1) to those detected by ELISA (Pyloriset EIA-GIII(®)).

RESULTS

By immunoblot, 82 cases (93.2%) were H. pylori positive, 10 of these cases (11.4%) were negative by ELISA and only 6 cases (6.8%) were negative by both ELISA and immunoblot. Multivariable odds ratio (OR) for noncardia GC comparing immunoglobulin G positive versus negative by ELISA was 6.8 [95% confidence interval (CI) 3.0-15.1], and by immunoblot, the OR was 21.4 (95% CI 7.1-64.4).

CONCLUSIONS

Using a western blot assay, nearly all noncardia GC were classified as H. pylori positive and the OR was more than threefold higher than the OR assessed by ELISA, supporting the hypothesis that H. pylori infection is a necessary condition for noncardia GC.

Management of precancerous conditions and lesions in the stomach (MAPS): guideline from the European Society of Gastrointestinal Endoscopy (ESGE), European Helicobacter Study Group (EHSG), European Society of Pathology (ESP), and the Sociedade Portuguesa de Endoscopia Digestiva (SPED)

Atrophic gastritis, intestinal metaplasia, and epithelial dysplasia of the stomach are common and are associated with an increased risk for gastric cancer. In the absence of guidelines, there is wide disparity in the management of patients with these premalignant conditions. The European Society of Gastrointestinal Endoscopy (ESGE), the European Helicobacter Study Group (EHSG), the European Society of Pathology (ESP) and the Sociedade Portuguesa de Endoscopia Digestiva (SPED) have therefore combined efforts to develop evidence-based guidelines on the management of patients with precancerous conditions and lesions of the stomach (termed MAPS). A multidisciplinary group of 63 experts from 24 countries developed these recommendations by means of repeat online voting and a meeting in June 2011 in Porto, Portugal. The recommendations emphasize the increased cancer risk in patients with gastric atrophy and metaplasia, and the need for adequate staging in the case of high grade dysplasia, and they focus on treatment and surveillance indications and methods.

EGILS consensus report. Gastric extranodal marginal zone B-cell lymphoma of MALT

This consensus report of the EGILS (European Gastro-Intestinal Lymphoma Study) group includes recommendations on the management of gastric extranodal marginal zone B-cell lymphoma of MALT. They are based on data from the literature and on intensive discussions and votings of the experts during their annual meetings.

Current concepts in the management of Helicobacter pylori infection: the Maastricht III Consensus Report

BACKGROUND

Guidelines on the management of Helicobacter pylori, which cover indications for management and treatment strategies, were produced in 2000.

AIMS

To update the guidelines at the European Helicobacter Study Group (EHSG) Third Maastricht Consensus Conference, with emphasis on the potential of H pylori eradication for the prevention of gastric cancer.

RESULTS

Eradication of H pylori infection is recommended in (a) patients with gastroduodenal diseases such as peptic ulcer disease and low grade gastric, mucosa associated lymphoid tissue (MALT) lymphoma; (b) patients with atrophic gastritis; (c) first degree relatives of patients with gastric cancer; (d) patients with unexplained iron deficiency anaemia; and (e) patients with chronic idiopathic thrombocytopenic purpura. Recurrent abdominal pain in children is not an indication for a "test and treat" strategy if other causes are excluded. Eradication of H pylori infection (a) does not cause gastro-oesophageal reflux disease (GORD) or exacerbate GORD, and (b) may prevent peptic ulcer in patients who are naïve users of non-steroidal anti-inflammatory drugs (NSAIDs). H pylori eradication is less effective than proton pump inhibitor (PPI) treatment in preventing ulcer recurrence in long term NSAID users. In primary care a test and treat strategy using a non-invasive test is recommended in adult patients with persistent dyspepsia under the age of 45. The urea breath test, stool antigen tests, and serological kits with a high accuracy are non-invasive tests which should be used for the diagnosis of H pylori infection. Triple therapy using a PPI with clarithromycin and amoxicillin or metronidazole given twice daily remains the recommended first choice treatment. Bismuth-containing quadruple therapy, if available, is also a first choice treatment option. Rescue treatment should be based on antimicrobial susceptibility.

CONCLUSION

The global burden of gastric cancer is considerable but varies geographically. Eradication of H pylori infection has the potential to reduce the risk of gastric cancer development.

Current concepts in the management of Helicobacter pylori infection: the Maastricht III Consensus Report

BACKGROUND

Guidelines on the management of Helicobacter pylori, which cover indications for management and treatment strategies, were produced in 2000.

AIMS

To update the guidelines at the European Helicobacter Study Group (EHSG) Third Maastricht Consensus Conference, with emphasis on the potential of H pylori eradication for the prevention of gastric cancer.

RESULTS

Eradication of H pylori infection is recommended in (a) patients with gastroduodenal diseases such as peptic ulcer disease and low grade gastric, mucosa associated lymphoid tissue (MALT) lymphoma; (b) patients with atrophic gastritis; (c) first degree relatives of patients with gastric cancer; (d) patients with unexplained iron deficiency anaemia; and (e) patients with chronic idiopathic thrombocytopenic purpura. Recurrent abdominal pain in children is not an indication for a "test and treat" strategy if other causes are excluded. Eradication of H pylori infection (a) does not cause gastro-oesophageal reflux disease (GORD) or exacerbate GORD, and (b) may prevent peptic ulcer in patients who are naïve users of non-steroidal anti-inflammatory drugs (NSAIDs). H pylori eradication is less effective than proton pump inhibitor (PPI) treatment in preventing ulcer recurrence in long term NSAID users. In primary care a test and treat strategy using a non-invasive test is recommended in adult patients with persistent dyspepsia under the age of 45. The urea breath test, stool antigen tests, and serological kits with a high accuracy are non-invasive tests which should be used for the diagnosis of H pylori infection. Triple therapy using a PPI with clarithromycin and amoxicillin or metronidazole given twice daily remains the recommended first choice treatment. Bismuth-containing quadruple therapy, if available, is also a first choice treatment option. Rescue treatment should be based on antimicrobial susceptibility.

CONCLUSION

The global burden of gastric cancer is considerable but varies geographically. Eradication of H pylori infection has the potential to reduce the risk of gastric cancer development.

Comparison of three PCR methods for detection of Helicobacter pylori DNA and detection of cagA gene in gastric biopsy specimens

AIM: To comparatively evaluate PCR and other diagnostic methods (the rapid urease test and/or culture) in order to determine which of the three PCR methods (ureA, glmM and 26-kDa, SSA gene) was most appropriate in the diagnosis of Helicobacter pylori (H pylori ) infection and also to evaluate the detection of a putative virulence marker of H pylori, the cagA gene, by PCR in biopsy specimens.

METHODS: One hundred and eighty-nine biopsy specimens were collected from 63 patients (three biopsies each) undergoing upper gastroduodenal endoscopy for various dyspeptic symptoms. The PCR methods used to detect H pylori DNA directly from biopsies were the glmM, 26-kDa, ureA and then cagA was used to compare the culture technique and CLO for urease with the culture technique being used as the gold standard.

RESULTS: Thirty-five percent of the biopsies were positive for H pylori DNA using the 3 PCR methods, while 68% of these were positive for the cagA gene. Twenty-four percent of the biopsies were negative for H pylori DNA in all PCR methods screened. The remaining 41% were either positive for ureA gene only, glmM only, 26-kDa only, or ureA + glmM, ureA + 26-kDa, glmM + 26-kDa. Out of the 35% positive biopsies, 41% and 82% were positive by culture and CLO respectively, while all negative biopsies were also negative by culture and cagA. Cag A+ infection was also predominantly found in H pylori DNA of the biopsies irrespective of the clinical diagnosis.

CONCLUSION: This method is useful for correctly identifying infections caused by H pylori and can be easily applied in our laboratory for diagnostic purposes.

Increase of arterial thrombosis parameters in chronic Helicobacter pylori infection in mice

An animal model was developed to study arterial thrombosis and determine if animals infected with Helicobacter pylori behave differently after induction of direct damage to blood vessels. Twenty-one C56/BL6 mice inoculated with the "Sydney strain" of H. pylori and 19 uninfected animals were kept for 1 year before testing. Vascular lesions were induced to mesenteric arterioles (15-25 microm diameter) by Argon laser. The dynamic course of thrombus formation was continuously monitored by a video camera for 10 min. Three parameters were assessed: (1) the number of laser pulses required to induce thrombus formation, (2) the number of platelet emboli removed by the blood flow and, (3) the duration of embolization. Additionally, blood was tested for platelet aggregation, fibrinogen, and cell count. Of the parameters measured, statistical differences between infected and uninfected mice concerned the number of emboli formed (6.00+/-2.18 infected vs. 3.89+/-1.37 non-infected, p=.0006) and the duration of embolization (2.41+/-0.73 min infected vs. 1.47+/-0.61 min non-infected p>.0001). A significant difference was also found in the fibrinogen levels between infected and uninfected mice. Chronic infection of mice with H. pylori leads to increased platelet embolization after damage to arterioles. These results are in favor of the possible involvement of H. pylori infection in the acute phase of coronary heart disease (CHD).

The seasonal distribution of campylobacter infection in nine European countries and New Zealand

In all temperate countries campylobacter infection in humans follows a striking seasonal pattern, but little attention has been given to exploring the epidemiological explanations. In order to better characterize the seasonal patterns, data from nine European countries and New Zealand have been examined. Several European countries with weekly data available showed remarkably consistent seasonal patterns from year to year, with peaks in week 22 in Wales, week 26 in Scotland, week 32 in Denmark, week 30 in Finland and week 33 in Sweden. In Europe, the seasonal peak was most prominent in Finland and least prominent in Scotland and Austria. In New Zealand the seasonality was less consistent since the peak was more prolonged. Possible explanations for the seasonal peaks are discussed. Research into the causes of campylobacter seasonality should help considerably in elucidating the sources of human infection.

Magnetic immuno-PCR assay with inhibitor removal for direct detection of Helicobacter pylori in human feces

A PCR protocol was developed to detect Helicobacter pylori in human stool specimens. This protocol was based on the association of a magnetic immuno-PCR assay with a technique to remove inhibitors (agarose-embedded DNA preparation). Of the 47 H. pylori-positive and 57 H. pylori-negative patients included in this study, 38 were positive and 66 were negative by this new protocol. The sensitivity, specificity, and predictive values for a positive or a negative result were 80.9% (95% confidence interval [CI], 66.3 to 90.4), 100% (95% CI, 92.1 to 100), 100% (95% CI, 88.6 to 100), and 86.4% (95% CI, 75.2 to 93.2), respectively.

Predictive factors for regression of gastric MALT lymphoma after anti-Helicobacter pylori treatment

BACKGROUND AND AIMS

Discrepant remission rates (41-100%) have been reported for patients with localised low grade gastric mucosa associated lymphoid tissue (MALT) lymphoma after eradication of Helicobacter pylori. The aim of this study was to explain these discrepancies and to determine the predictive factors of gastric lymphoma regression after anti- H pylori treatment.

PATIENTS AND METHODS

Forty six consecutive patients with localised gastric MALT lymphoma (Ann Arbor stages I(E) and II(E)) were prospectively enrolled. All had gastric endoscopic ultrasonography and H pylori status assessment (histology, culture, polymerase chain reaction, and serology). After anti-H pylori treatment, patients were re-examined every four months.

RESULTS

Histological regression of the lymphoma was complete in 19/44 patients (43%) (two lost to follow up). Median follow up time for these 19 responders was 35 months (range 10-47). No regression was noted in the 10 H pylori negative patients. Among the 34 H pylori positive patients, the H pylori eradication rate was 100%; complete regression rate of the lymphoma increased from 56% (19/34) to 79% (19/24) when there was no nodal involvement at endoscopic ultrasonography. There was a significant difference between the response of the lymphoma restricted to the mucosa and other more deep seated lesions (p<0.006). However, using multivariate analysis, the only predictive factor of regression was the absence of nodal involvement (p<0.0001).

CONCLUSION

In H pylori positive patients with localised gastric MALT lymphoma, carefully evaluated and treated without any lymph node involvement assessed by endoscopic ultrasonography, complete remission of lymphoma was reached in 79% of cases.

Resistance of t(11;18) positive gastric mucosa-associated lymphoid tissue lymphoma to Helicobacter pylori eradication therapy

20-30% of gastric mucosa-associated lymphoid tissue (MALT) lymphoma associated with Helicobacter pylori do not regress after antibiotic therapy. Regression can be assessed only by extended follow-up. To assess whether t(11;18, q21;q21), which results in a chimeric transcript between the AP12 and MLT genes, predicts lymphoma resistance to antibiotic therapy, we screened for the fusion transcript with RT-PCR in ten responsive and 12 non-responsive gastric MALT lymphomas. The AP12-MLT transcript was detected in nine (75%) of 12 patients non-responsive to antibiotic therapy but not in responsive patients. Most H pylori-associated gastric MALT lymphomas that do not respond to antibiotic therapy are associated with t(11;18, q21;q21).

Cytoskeletal rearrangements induced by Helicobacter pylori strains in epithelial cell culture: possible role of the cytotoxin

The relationship between Helicobacter pylori adherence, cytotoxin production, and modification of the cytoskeletal structure was investigated by studying the effects of 12 H. pylori strains cocultured with Hep-2 epithelial cells. Bacterial strains were isolated from patients with peptic ulcer disease or nonulcer dyspepsia. Presence of the cag pathogenicity island and vacA subtypes of the strains were determined as was the production of vacuolating cytotoxin. We found that cytoskeletal rearrangements, as observed by confocal microscopy after double staining of the bacteria and the cell actin with Texas red and fluorescein-conjugated phalloidin, respectively, occurred essentially when the strains were cytotoxin producers and that the supernatants alone could also lead to these modifications.

Double vs. single dose of pantoprazole in combination with clarithromycin and amoxycillin for 7 days, in eradication of Helicobacter pylori in patients with non-ulcer dyspepsia

BACKGROUND

The necessity of increasing intragastric pH during eradication treatment in Helicobacter pylori infected patients is well established. However, the optimal dose of the proton pump inhibitors used in eradication regimen is still a subject of debate.

AIMS

To compare the efficacy and tolerability of a double vs. a single daily dose of pantoprazole in a 7-day triple therapy in eradicating H. pylori.

METHODS

In this regional, multicentre, comparative, randomized and double-blind study, H. pylori-positive patients with non-ulcer dyspepsia were treated for 7 days with clarithromycin 500 mg b.d. and amoxycillin 1000 mg b.d. and either a double (2 x 40 mg, Group 2PCA) or a single (40 mg, Group 1PCA) daily dose of pantoprazole. H. pylori infection was assessed at entry and at the end (day 38) of the study by histology and culture, or in some cases by 13C-urea breath test.

RESULTS

From 203 patients recruited, 192 patients (96 in Group 2PCA and 96 in Group 1PCA) formed the intention-to-treat population. Twenty-six of them judged as major protocol violators were excluded from the per protocol analysis. H. pylori eradication rate was 75% in Group 2PCA and 56% in Group 1PCA in intention-to-treat analysis, and 80% in Group 2PCA and 59% in Group 1PCA in per protocol analysis (P < 0.05). The primary resistance to clarithromycin was 10.5%. The eradication rates for the clarithromycin susceptible strains were 86% for Group 2PCA and 71% for Group 1PCA in per protocol analysis (P < 0.05). Both regimens led to similar improvement of clinical symptoms and were equally well tolerated.

CONCLUSION

A double (2 x 40 mg) daily dose of pantoprazole in a 7-day triple therapy is more effective than a single (40 mg) dose of this drug in eradication of H. pylori.

Laser assisted ratio analyser 13C-urea breath testing, for the detection of H. pylori: A prospective diagnostic European multicentre study

BACKGROUND

Novel technology based on laser optogalvanic spectroscopy called the LARA (Laser Assisted Ratio Analyser) system was developed to measure 12C/13C ratios in breath samples using stable 13C isotopes, to detect Helicobacter pylori infection.

AIM

To determine the sensitivity and specificity of the 13C-LARA-urea breath test in the detection of H. pylori infection in a prospective European multicentre trial; FDA-and EMEA-approved.

METHODS

Consecutive dyspeptic patients underwent diagnostic gastroscopy with biopsies for culture and histopathology, to detect H. pylori infection (gold standard). Subsequently, the LARA-urea breath test was performed using either a system without a cold trap (part I) or a system with a cold trap (part II). In both instances baseline, 30-min and 60-min breath samples were collected. The optimum cut-off level for 12C/13C ratios was determined by Receiver Operator Characteristics analysis.

RESULTS

In part I, 544 out of 604 patients were evaluable (low CO2: 47; withdrawn: 13). 284 out of 544 patients (52%) were H. pylori-positive according to the gold standard. The sensitivity of the LARA-urea breath test was 95% and the specificity 94%. In part II, 257 out of 272 were evaluable (low CO2: 14; withdrawn: 1). Sensitivity and specificity were 93% and 96%, respectively.

CONCLUSION

The LARA-technology represents an accurate and non-invasive testing system for the detection of H. pylori infection. Its major advantages are the use of stable 13C isotope, the high throughput of samples and the easy means of collecting, storing and transporting the samples, thus making the system convenient to both patient and clinician.

Low prevalence of monoclonal B cells in Helicobacter pylori gastritis patients with duodenal ulcer

We have studied the prevalence of B-cell clonality among a large group of 320 patients with Helicobacter pylori gastritis and duodenal ulcer. These patients underwent endoscopic examination with multiple gastric biopsies at diagnosis and were followed 2 and 12 months after therapy. Histopathologic examination of 809 sets of biopsy specimens showed lymphoid gastritis with lymphoid aggregates or follicles, but without lymphoepithelial lesion, in 302 samples corresponding to initial biopsy specimens (n=130) or to posttreatment biopsy specimens (n=172). DNA extracted from fresh antral specimens allowed the amplification of Helicobacter pylori DNA in all cases before therapy. The arrangement of the immunoglobulin heavy chain gene was studied by polymerase chain reaction (PCR) in the 302 selected lymphoid gastritis samples. Single or dominant bands were seen only in four specimens from three patients (1.3%), whereas a polyclonal pattern was seen in the other 298 samples. The detection threshold of our PCR technique was approximately 3% of clonal B cells diluted in a polyclonal population. This threshold appeared to be a reliable cutoff between polyclonal gastritis and clonal MALT lymphoma. In our experience, Helicobacter pylori lymphoid gastritis appeared mainly as a benign polyclonal condition.

Effects of cefixime or co-amoxiclav treatment on nasopharyngeal carriage of Streptococcus pneumoniae and Haemophilus influenzae in children with acute otitis media

A multicentre, open-label, randomized study was performed in 501 out-patients with acute otitis media, aged 6-36 months, to study the impact of treatment with either cefixime suspension 8 mg/kg/day bd or co-amoxiclav suspension 80 mg/kg/day tds for 10 days on nasopharyngeal carriage of Streptococcus pneumoniae and Haemophilus influenzae. Of 426 patients with nasopharyngeal cultures at entry to the trial, end of treatment and at follow-up visit (35 days after inclusion), significant changes in carriage of S. pneumoniae were observed. The proportion of penicillin-resistant S. pneumoniae was higher in the samples taken at the end of treatment and follow-up than in those taken at inclusion, while the total number of children with this microorganism was lower. The difference at the end of treatment was greater with co-amoxiclav than with cefixime. For H. influenzae the resistance rate remained steady while the number of children with this microorganism decreased. At follow-up there was no significant difference between the two groups in terms of nasopharyngeal positive culture for S. pneumoniae or H. influenzae. Despite these differences, successful clinical responses were similar at the end of treatment and at follow-up.

Heterogeneity of immunoglobulin G response to Helicobacter pylori measured by the unweighted pair group method with averages

The heterogeneity of the immune response to Helicobacter pylori has always been noticed but has never been evaluated by obtaining a quantitative measure. For this purpose, sera were tested by enzyme-linked immunosorbent assay, and 207 positive serum specimens were subsequently tested by immunoblotting. The presence or absence of six specific bands was noted. The homology of the different profiles of bands was measured by calculating the Dice coefficient, and a dendrogram was constructed. Thirty-four profiles were found, with each profile containing from 1 to 43 serum specimens. At a level of 72% similarity, 115 of the serum specimens studied fell into eight profiles. At a level of 48% similarity, 186 of the serum specimens studied fell into 22 profiles. The difference in immunoblot profiles was probably linked to the host immune response, but infection with strains carrying different antigens cannot be ruled out.

Short-course therapy with amoxycillin-clarithromycin triple therapy for 10 days (ACT-10) eradicates Helicobacter pylori and heals duodenal ulcer. ACT-10 Study Group

BACKGROUND

Whilst the role of Helicobacter pylori eradication in managing duodenal ulcers has been established, consensus regarding the ideal regimen has not been achieved.

METHODS

Patients with H. pylori-positive active duodenal ulcer were randomly assigned to receive triple therapy with amoxycillin 1000 mg b.d. + clarithromycin 500 mg b.d. + omeprazole 20 mg daily for 10 days (ACT-10) or dual therapy with clarithromycin 500 mg t.d.s. + omeprazole 40 mg daily for 14 days (Dual). No additional acid suppression was provided following eradication therapy. Endoscopy, with biopsy for culture and histology, as well as 13C-urea breath testing (13C-UBT) were performed pre-treatment to assess H. pylori infection. H. pylori eradication was established at 4-6 weeks follow-up with culture (2 antral, 1 corpus biopsies), histology (2 antral biopsies), and 13C-UBT. Ulcer healing by endoscopy and change in clinical symptoms were also assessed at 4-6 weeks.

RESULTS

Two hundred and sixty-seven (267) patients were randomized to ACT-10 (n = 137) or Dual therapy (n = 130). By per-protocol and intention-to-treat analyses, H. pylori eradication at 4-6 weeks follow-up was 91% (115/127) and 88% (120/136), respectively, for ACT-10 patients and 59% (68/115) and 55% (72/130), respectively, for Dual therapy patients (P < 0.001 for both analyses). Ulcer healing was high in both treatment groups: ACT-10, 93% (118/127) and 90% (122/136), respectively; and Dual therapy, 91% (104/114) and 85% (111/130), respectively. Pre-treatment resistance to clarithromycin was low (4%, 8/214) as compared to metronidazole resistance which was over 40%. Emergence of resistance to clarithromycin was observed in 2% of patients receiving ACT-10 and in 25% of those receiving Dual therapy. ACT-10 and Dual therapy patients experienced similar rates of drug-related adverse events (33% vs. 32%, respectively) and discontinuation from therapy due to an adverse event (1.5% vs. 5%, respectively). More than 90% of patients were compliant with each prescribed medication.

CONCLUSION

In patients with active duodenal ulcer, a 10-day course of amoxycillin-clarithromycin-based triple therapy without additional acid suppression is highly effective in eradicating H. pylori and healing duodenal ulcer.

Transportation of Helicobacter pylori cultures by optimal systems

Cultures of Helicobacter pylori on chocolate agar slants in bijou bottles and on chocolate agar plates inside BBL Campy Pouches were mailed from Dublin to Galway, Ireland; Bordeaux, France; and Beijing, China. Both systems maintained viability of H. pylori for at least 4 days under mailing conditions. Ninety percent of the isolates on the slants survived for 6 days, but only 30% of the isolates in the pouches survived. When the slants were stored at 4 degrees C after arrival, 50% of the isolates were recoverable 10 days after mailing. Failure of recovery was due to coccoid formation by the organisms. Contamination was not a problem in either system. Chocolate agar slants are considered the more suitable system for transporting H. pylori cultures, especially when transport time longer than 4 days is expected.

The cohort effect and Helicobacter pylori

A total of 631 serum samples collected in 1969, 1979, and 1989 from adults and children were screened for Helicobacter pylori by Western blot analysis. Results showed that H. pylori seroprevalence has become less frequent over the 20-year period. By studying seropositivity by year of birth, the magnitude of a cohort effect of H. pylori seropositivity was estimated. The odds of being seropositive decreased by 26% per decade, P = .008 (95% confidence interval, 8%-41%). Estimates of seroprevalence adjusted for both age-specific variation and the cohort effect suggest that most seropositivity in adults occurs by the age of 15 years. The implication of these findings is that H. pylori infection is becoming less frequent and is predominantly acquired in childhood.

A collaborative study of the in-vitro sensitivity to RP 59500 of bacteria isolated in seven hospitals in France

The in-vitro activity of RP 59500 was determined against 1051 recent clinical bacterial isolates. The susceptibility to RP 59500 was determined with an agar dilution technique for all the isolates, while MICs and MBCs were determined for 82 selected strains in broth. Isolates of both Staphylococcus aureus and coagulase-negative staphylococci appeared to be potentially susceptible to RP 59500, independent of susceptibility to methicillin or MLS resistance. (S. aureus: methicillin-sensitive, MIC90, 1.0 mg/L; methicillin-resistant, MIC90 1.0 mg/L; coagulase-negative staphylococci: methicillin-sensitive, MIC90 0.5 mg/L). Lancefield group A, B, C and G streptococci (MIC50 0.5 and MIC90 1.0 mg/L) and Streptococcus pneumoniae (MIC50 0.5 and MIC90 1.0 mg/L) appeared to be susceptible to RP 59500. Some Streptococcus spp. and enterococci as well as Listeria monocytogenes were inhibited by a higher concentration of RP 59500 (enterococci: MIC90 4 mg/L, range 0.125-16 mg/L). Comparatively low MICs were seen when Legionella spp., Neisseria gonorrhoeae and Gardnerella vaginalis were tested. Broth dilution MIC/MBC determinations showed no evidence of tolerance, as MIC values were within two dilutions of MBC values. RP 59500 might be a useful compound in the treatment of infections caused by a range of Gram-negative and Gram-positive bacteria, including those resistant to methicillin and/or macrolides.

Bactericidal effect of amoxicillin on Helicobacter pylori in an in vitro model using epithelial cells

The treatment of Helicobacter pylori with antimicrobial agents has largely been ineffective, and susceptibility results are in disagreement with those obtained by standard in vitro testing. The bactericidal effect of amoxicillin was tested in an in vitro model by using sessile bacteria attached to HEp-2 cells; this bactericidal effect was compared with that against planktonic bacteria. Viable cell counts were performed by standard procedures after 1, 6, and 24 h of contact with the antibiotic at different concentrations. A bactericidal effect (99.9% killing) was observed against sessile bacteria after 24 h with concentrations of only 10, 1, and 0.1 mg/liter, while against planktonic bacteria it was also noted at concentrations of 0.01 and 0.001 mg/liter, and the effect was observed after 6 h with the three highest concentrations. When the results for five strains were studied by analysis of variance at 6 and 24 h, the main variable was the antibiotic concentration, followed by the culture conditions, e.g., planktonic or sessile bacteria, the strain tested, and the time of contact. A decreased pH of 5.4 did not affect the action of amoxicillin. The bactericidal effect of the combination of amoxicillin and metronidazole was additive against sessile H. pylori.

Search for Campylobacter species in the public water supply of a large urban community

A survey of the water distribution network of a large urban community was performed during a one year period. In addition to standard indicator bacteria, Campylobacter species were looked for after filtration of 500 ml water samples by enrichment of the original filter followed by subculture on a Skirrow's medium as well as a direct filtration procedure on a non selective agar. All steps were performed at 37 degrees C. Specimens collected at the springs (206), treatment stations (206) and at different points along the network (479) were tested. Fourteen strains of Campylobacter were isolated. They were cephalothin resistant and hippurate negative but they did not grow at 42 degrees C. None of them was part of the enteropathogenic Campylobacters. All except one were found in untreated water; in 11 cases among 13 tested, standard indicator bacteria were positive. We conclude that there is a low incidence of Campylobacter species in the water supply tested, that they are sensitive to chlorination and that testing standard indicator bacteria is an effective indicator for Campylobacter species.

Identification and classification of Campylobacter strains by using nonradioactive DNA probes

Acetylaminofluorene-labeled genomic DNA probes were used for the identification and classification of Campylobacter strains. Relationships among 17 well-known strains of Campylobacter species and subspecies were studied by comparing acetylaminofluorene- or 32P-labeled probes. Results obtained with both methods were closely correlated and were in agreement with those already reported. In an identification experiment, hybridization with nonradioactive probes was performed on 60 strains isolated from stool samples after subculturing and quick DNA extraction; conventional biochemical tests were conducted in parallel. A good correlation was found between the results obtained by nonradioactive hybridization and by biochemical tests. Thus, the acetylaminofluorene-labeled genomic DNA probe method is an interesting alternative for laboratories without access to radioisotopes for the identification and classification of bacteria.

Campylobacter hyointestinalis: an opportunistic enteropathogen?

A new case of Campylobacter hyointestinalis-associated diarrhea in a human is reported. The medical history of the patient was significant for immunodeficiency because of an evolutive chronic myeloid leukemia. The diarrhea rapidly stopped after administration of oral erythromycin. No other enteropathogenic agent was found by routine examination of stools. Although neither serology nor autopsy was available, this observation appears to be suggestive of the possible enteropathogenicity of C. hyointestinalis for patients at risk.

[Sensitivity of Campylobacter to 2 new groups of beta-lactams]

One hundred strains of Campylobacter (44 C. jejuni, 34 C. coli, and 22 C. fetus ssp. fetus) were tested with two new groups of beta-lactams:monobactams (azthreonam and carumonam) and carbapenem (imipenem). MICs were determined by using an agar dilution technique. The monobactams were not effective against Campylobacter species. In contrast, imipenem showed a high activity (MIC 90, 0.25 mg/l). Clinical trials will indicate if this compound can be used in the therapy of severe Campylobacter infections.

[Clinical and bacteriological evaluation of cefmenoxime in the newborn infant]

Cefmenoxime (CMX) has been administered under parenteral injection to 39 neonates delivered at term, nearly always by monotherapy in an average dosage of 86.8 mg/kg/day. CMX has been used 31 times in first line therapy and 8 times after failure of association Ampicillin-Gentamicin. 25 strains have been identified: 16 E. coli (9 Ampicillin resistant), 7 P. mirabilis (1 Ampicillin resistant), 1 K. oxytoca and 1 Streptococcus B. The neonates group with septicaemia (1 with arthritis) has been cured without after-effects as urinary tract infections and systemic infections. 2 respiratory tract infections have been improved, the others have been cured. Bacterial samples have always been sterilized within 2 days. Local tolerance (IV or/and IM injection) has been very good. No clinical or biological abnormality has been imputed to treatment. Cefmenoxime appears very effective on enterobacteriaceae (MIC range 0.05-0.5 mg/l) and can be used in newborn infections.

[Bacteriological study of acute otitis media in children. Therapeutic consequences]

One hundred children presenting with acute otitis media underwent a bacteriological study of otitis exudate over a 18 month period. The bacteria found were as follows: Streptococcus pneumoniae (24), Haemophilus influenzae (19), Staphylococcus aureus (12), Streptococcus pyogenes (7), Branhamella catarrhalis (3), and 18 Gram negative bacilli (including 7 Pseudomonas aeruginosa and 11 enterobacteriaceae). One pathogenic bacterium was isolated in 56 cases, 2 or more in 12 cases and none in 32 cases. In the age categories 0-1 year (47 cases) and 1-3 years (31 cases), S. pneumoniae and H. influenzae were the main organisms found, followed by S. pyogenes in children older than 3 years (22 cases). With respect to the antibiotics used for treating otitis, 5/22 S. pneumoniae and 4/17 H. influenzae were erythromycin resistant (9/17 had an intermediate susceptibility) and 7/19 H. influenzae and 1/17 S. pneumoniae were cotrimoxazole resistant. None of the S. pneumoniae and 2/19 H. influenzae were ampicillin resistant. These 2 H. influenzae and 2/3 B. catarrhalis were beta-lactamase producers. They were sensitive to the combination of amoxicillin with clavulanic acid.