High Level of Antimicrobial Resistance in French Helicobacter pylori Isolates

Background:  Helicobacter pylori is a human pathogen responsible for serious diseases including peptic ulcer disease and gastric cancer. The recommended triple therapy included clarithromycin but increasing resistance has undermined its effectiveness. It is therefore important to be aware of the local prevalence of antimicrobial resistance to adjust treatment strategy.
Materials and Methods:  Overall, 530 biopsies were collected between 2004 and 2007. The antimicrobial susceptibility of H. pylori was determined by E-test and molecular methods.
Results:  Among these, 138/530 (26%) strains were resistant to clarithromycin, 324/530 (61%) to metronidazole and 70/530 (13.2%) to ciprofloxacin. Whereas no resistance against amoxicillin and tetracycline was observed, only one strain was resistant to rifampicin. Compared to the patients never treated for H. pylori infection, the prevalence of resistance was significantly higher in patients previously treated (19.1% vs 68% for clarithromycin; 13.2% vs 53.3% for both clarithromycin and metronidazole). The trend analysis revealed an increase of primary resistance to ciprofloxacin between 2004 and 2005 (7.3%) vs 2006–2007 (14.1%) ( p  = .04) and the secondary resistance reached 22.7% in 2007. Interestingly, 27 biopsies (19.6%) contained a double population of clarithromycin-susceptible and -resistant strains.
Conclusions:  The reported high prevalence of clarithromycin and multiple resistances of H. pylori suggest that the empiric therapy with clarithromycin should be abandoned as no longer pretreatment susceptibility testing has assessed the susceptibility of the strain. As culture and antibiogram are not routinely performable in most clinical laboratories, the use of molecular test should be developed to allow a wide availability of pretreatment susceptibility testing.     

Prevalence and mechanisms of resistance to fluoroquinolones in Helicobacter pylori strains from patients living in Belgium

BACKGROUND: Because of the increasing resistance of Helicobacter pylori against metronidazole and clarithromycin, alternative regimens including newer fluoroquinolones have been developed. We aimed to assess the prevalence as well as the mechanisms of this resistance in clinical isolates originating from patients living in Belgium. METHODS: Minimal inhibitory concentration (MIC) values of ciprofloxacin, levofloxacin, and moxifloxacin were determined by Etest method on 488 H. pylori isolates originating from patients who underwent upper gastrointestinal endoscopy at 10 different centers. Resistant strains (MIC values > 1 microg/ml) were evaluated for the presence of point mutations in the quinolone resistance-determining region (QRDR) of the gyrA by amplification and nucleotide sequence. RESULTS: Eighty-two (16.8%) of the strains were found resistant to all fluoroquinolones and 70 of these were further analyzed. Homogeneous and heterogeneous resistance were observed in 55 (78.6%) and in 15 (21.4%) of the strains, respectively. QRDR sequencing revealed various mutations of the codons corresponding to Asn-87 and Asp-91 in all isolates with homogeneous resistance. However, in 12 of 15 strains displaying heterogenous resistance, mutations were only detected after subcultures of isolated colonies growing within the ellipse inhibition zone of the E-test. Amino acid substitutions in the QRDR of GyrA could not be directly related with the MIC values of the isolates. Fluoroquinolone-resistant mutants were easily selected in vitro at frequencies ranging between 10(-6) and 10(-7). Such selected mutants stably persisted after several serial passage in antibiotic-free agar. CONCLUSIONS: These results suggest that H. pylori resistance to fluoroquinolones is occurring at a high frequency in the Belgian population and that it is essentially mediated through a variety of point mutations occurring in a few loci of GyrA. As a consequence, we strongly suggest to determine the susceptibility of the infecting isolates to fluoroquinolones before administration of an anti-H. pylori regimen including these agents.     

The Modified Sequential Treatment Regimen Containing Levofloxacin for Helicobacter pylori Eradication in Turkey

Background:  Eradication rates of Helicobacter pylori have declined to unacceptable levels in recent years. New and effective treatment options are warranted both as a first and second line treatment.
Aim:  To test an effectiveness of modified sequential therapy with levofloxacin for H. pylori eradication in Turkey.
Material and Methods:  Helicobacter pylori infected dyspeptic patients were included to the study. Subjects were treated with modified sequential therapy consisting of rabeprazole 20 mg b.i.d. and amoxicillin 1 g b.i.d., for 7 days followed by rabeprazole 20 mg b.i.d, levofloxacin 500 mg q.d. and metronidazole 500 mg b.i.d for the remaining 7 days.
Results:  Sixty-three treatment naive patients and 37 previous treatment failures were enrolled to the study (59 F, 41 M, age: 21–80 years). There was five drop out. Helicobacter pylori eradication was achieved in 80 patients, intention-to-treat (ITT): 80% (95% CI: 71–87%) and per-protocol (PP): 84.2% (95% CI: 75–91%), totally. In treatment naive patients ITT and PP eradication rates were 82.5% (95% CI: 71–91%), and 86.7% (95% CI: 75–94%), respectively. As a second line treatment eradication was successful in ITT 75.7%.(95% CI: 59–88%), and PP 80% (95% CI: 63–92%).Mild side effects were reported by 8 patients (8.4%).
Conclusions:  Sequential therapy using "rabeprazole and amoxicillin 7 days followed by rabeprazole, metronidazole and levofloxacin for 7 days" is a new regimen with acceptable eradication rates in naïve patients in Turkey. Further modifications in the dose or duration of this new sequential therapy might increase its effectiveness as both first and second line treatment.     

Primary levofloxacin resistance and gyrA/B mutations among Helicobacter pylori in Japan

BACKGROUND: Recent years have witnessed a decrease in the rate of Helicobacter pylori eradication due to antimicrobial resistance, clarithromycin or metronidazole resistance in particular. As one of the alternatives to the standard regimens, levofloxacin-containing therapy has been considered a promising regimen. Nevertheless, there is a little information concerning the prevalence of levofloxacin resistance and this resistance mechanism. MATERIALS AND METHODS: Levofloxacin susceptibility was examined using E-test in 507 H. pylori strains clinically isolated in Japan from 2001 to 2004. Mutation patterns in the quinolone resistance-determining regions of the gyrA and gyrB genes were evaluated, performing direct sequencing of 68 levofloxacin-resistant and 50 susceptible strains. RESULTS: Primary levofloxacin resistance was found in 76 (15.0%) strains. Fifty-seven (83.8%) of 68 levofloxacin-resistant strains analyzed had point mutations in gyrA at Asn-87 or Asp-91, while seven (14.0%) of 50 susceptible strains had gyrA mutations. There was a significant difference in the occurrence of gyrA mutations between levofloxacin-resistant and -susceptible strains (p < .001). In levofloxacin-resistant strains, the occurrence of gyrA mutations at Asn-87 was most common regardless of minimal inhibitory concentration levels, and that of gyrA mutations at Asp-91 tended to be associated with low-level resistance. A double gyrA mutation at Asn-87 and Asp-91 might have an additional impact. As for gyrB, three (4.4%) of 68 levofloxacin-resistant strains with no susceptible strains had mutations. CONCLUSIONS: Primary levofloxacin resistance was common in Japan and primarily related to gyrA mutations at Asn-87 and Asp-91.     

Acetylation of fluoroquinolone antimicrobial agents by an Escherichia coli strain isolated from a municipal wastewater treatment plant

Aims:  To isolate environmental bacteria capable of transforming fluoroquinolones to inactive molecules.
Methods and Results:  Bacteria were isolated from the aerobic liquor of a wastewater treatment plant on a medium containing norfloxacin (100 mg l⁻¹). Twenty-two isolates were highly resistant (minimal inhibitory concentration: 6·25−200 μg ml⁻¹) to five fluoroquinolones and six of them were positive by PCR amplification for the aminoglycoside resistance gene aac(6')-Ib. Of these, only Escherichia coli strain LR09 had the ciprofloxacin-acetylating variant gene aac(6')-Ib-cr ; HPLC and mass spectrometry showed that this strain transformed both ciprofloxacin and norfloxacin by N -acetylation. This bacterium also had mutations in the quinolone-resistance determining regions of the gyrA and parC genes.
Conclusions:  An E. coli isolate from wastewater, which possessed at least two distinct fluoroquinolone resistance mechanisms, inactivated ciprofloxacin and norfloxacin by N -acetylation.
Significance and Impact of the Study:  This is the first report of N -acetylation of fluoroquinolones by an aac(6')-Ib-cr -containing bacterium from an environmental source.     

A Population-Based Epidemiologic Study of Helicobacter Pylori Infection and its Association with Systemic Inflammation

Background:  Infection with Helicobacter pylori is associated with a variety of non-gastrointestinal sequelae. These may be mediated by an increase in systemic inflammation. We assessed if serologic evidence of infection with H. pylori is associated with increased serum C-reactive protein (CRP) levels.
Methods:  The study design consisted of a randomly selected, cross-sectional population-based study of 2633 individuals phenotyped in 1991, of whom 2361 participants provided serum samples to permit measurement of H. pylori 's serologic status and CRP levels.
Results:  Male gender (odds ratio (OR): 1.65; 95% confidence interval (CI): 1.23–2.21), age (OR per year: 1.05; 95% CI: 1.04–1.06), height (OR per meter: 0.05; 95% CI: 0.01–0.24), current smoking habit (compared with never smokers, OR: 1.46; 95% CI: 1.13–1.88), and less affluent socioeconomic status were associated with increased odds of being seropositive for H. pylori . Helicobacter pylori infection was associated with increased risk of having an elevated serum CRP (above 3 mg/L) after adjustment for gender, age, height, smoking status, and socioeconomic status (OR: 1.32; 95% CI: 1.05–1.67). Similar associations were seen using a threshold for elevated serum CRP of greater than 1 mg/L.
Conclusions:  Our data suggest that infection with H. pylori is associated with increased systemic inflammation. This suggests one potential mechanism to explain the extra-gastrointestinal conditions associated with H. pylori infection.     

Meta-Analysis: The Effect of Supplementation with Lactoferrin on Eradication Rates and Adverse Events During Helicobacter pylori Eradication Therapy

Background: Recent evidence shown that lactoferrin could exert an antimicrobial effect against Helicobacter pylori both in vitro and in vivo models. To systematically evaluate whether adding lactoferrin to H. pylori eradication regimens could improve eradication rates and reduce side-effects during anti- H. pylori treatment.
Materials and Methods:  Eligible articles were identified by searches of electronic databases. We included all randomized trials comparing lactoferrin supplementation to placebo or no treatment during anti- H. pylori regimens. Statistical analysis was performed with Review Manager 5.0.10. Subanalysis/Sensitivity analysis was also performed.
Results: We identified nine randomized trials (n = 1343). Pooled H. pylori eradication rates were 86.57% (95% confidence interval (CI) = 83.99–89.15%) and 74.44% (95% CI = 71.14–77.74%) for patients with or without lactoferrin by intention-to-treat analysis, respectively, the odds ratio (OR) was 2.26 (95% CI = 1.70–3.00); the occurrence of total side-effects was 9.05% (95% CI = 6.83–11.27%) and 16.28% (95% CI = 13.43%–19.13%) for groups with or without lactoferrin, especially for nausea, the summary OR was 0.15 (95% CI = 0.04–0.54).
Conclusions: Our review suggests that supplementation with lactoferrin could be effective in increasing eradication rates of anti- H. pylori therapy, and could be considered helpful for patients with eradication failure. Furthermore, lactoferrin shows a positive impact on H. pylori therapy-related side-effects.     

Meta-Analysis: Lactobacillus Containing Quadruple Therapy Versus Standard Triple First-Line Therapy for Helicobacter pylori Eradication

Background:  Recent evidence showed that Lactobacilli could exert an inhibitory effect on Helicobacter pylori both in vitro and in vivo models. To systematically evaluate whether adding Lactobacilli to H. pylori eradication regimens could improve eradication rates and reduce side effects during anti- H. pylori treatment.
Materials and Methods:  Eligible articles were identified by searches of electronic databases. We included all randomized trials comparing Lactobacilli supplementation to placebo or no treatment during anti- H. pylori regimens. Statistical analysis was performed with Review Manager 5.0.10. Subanalysis analysis was also performed.
Results:  We identified eight randomized trials (n = 1372). Pooled H. pylori eradication rates were 82.26% (95% CI = 78.01–86.51%) and 76.97% (95% CI = 73.11–80.83%) for patients with or without Lactobacilli by intention-to-treat analysis, respectively, the odds ratio (OR) was 1.78 (95% CI = 1.21–2.62). The occurrence of total side effects had no significant difference and were 30.84% (95% CI = 24.82–36.86%) and 42.24% (95% CI = 35.89%–48.59%) for two groups, the summary OR was 0.49 (95% CI = 0.24–1.02); However, Lactobacilli supplementation group had lower occurrence of diarrhoea, bloating and taste disturbance.
Conclusions:  Our review suggests that supplementation with Lactobacilli could be effective in increasing eradication rates of anti- H. pylori therapy for first-treated patients. Furthermore, Lactobacilli showed a positive impact on some H. pylori therapy-related side effects.     

Evaluation of a novel monoclonal-based antigen-in-stool enzyme immunoassay (Premier Platinum HpSA PLUS) for diagnosis of Helicobacter pylori infection in Vietnamese children

Background: Helicobacter pylori infection is difficult to diagnose in children, especially in developing countries where noninvasive methods such as urea breath test are often not available. We evaluate the sensitivity and specificity of a new monoclonal antibody-based antigen-in-stool enzyme immunoassay (Premier Platinum HpSA PLUS) for diagnosis of H. pylori infection in Vietnamese children.
Materials and Methods: Sensitivity of the antigen-in-stool test was evaluated in 232 children, 3–15 years of age, who were positive for H. pylori infection by culture from biopsies. For evaluation of the specificity 98 children of similar age with nongastrointestinal conditions and who were negative for H. pylori infection by serologic assays were included with blood and stool samples.
Results: Of the 232 culture-positive children, 224 were also positive by Premier Platinum HpSA PLUS. Of the 98 control children, 93 were H. pylori negative also in the stool test. The sensitivity of Premier Platinum HpSA PLUS was thus 96.6% (95% CI 93.3–98.5) and the specificity was 94.9% (95% CI 88.5–98.3).
Conclusions: The findings have demonstrated Premium Platinum HpSA PLUS to be a reliable method for detection of H. pylori infection also in children in our area.     

Helicobacter pylori and Gastroesophageal Reflux Disease: A Case–Control Study

Background:  Gastric colonization with Helicobacter pylori is a proposed protective factor against gastroesophageal reflux disease (GERD), but little population-based data exist and other data conflict.
Methods:  We conducted a case–control study within the membership of a large integrated health-care system that compared GERD-free subjects with two groups: subjects with a physician-assigned GERD diagnosis and randomly selected members with self-described weekly GERD symptoms. Subjects completed interviews, GERD questionnaires, and antibody testing for H. pylori and its cagA protein.
Results:  Serologic data were available for 301 physician-assigned GERD patients, 81 general membership subjects with GERD symptoms, and 175 general membership subjects without GERD symptoms. Physician-assigned GERD patients were less likely to have H. pylori antibodies than GERD-free member controls (odds ratio (OR) = 0.27, 95% confidence interval (CI) 0.15–0.47); there was also an inverse association between H. pylori and GERD symptom severity (OR = 0.18, 95% CI 0.08–0.41; severe or very severe symptoms) and GERD frequency (OR = 0.18, 95% CI 0.09–0.38; for symptoms at least weekly). The association was stronger among persons with erosive GERD and was similar between H. pylori -positive subjects with and without cagA. There was no association among persons who were cagA positive, but H. pylori negative. Similar findings were found in analyses of the general membership with self-described GERD symptoms.
Conclusions:  H. pylori antibody status was inversely associated with a GERD diagnosis and GERD symptoms compared with a general membership population.     

New insights into fluoroquinolone resistance in Mycobacterium tuberculosis: functional genetic analysis of gyrA and gyrB mutations

Fluoroquinolone antibiotics are among the most potent second-line drugs used for treatment of multidrug-resistant tuberculosis (MDR TB), and resistance to this class of antibiotics is one criterion for defining extensively drug resistant tuberculosis (XDR TB). Fluoroquinolone resistance in Mycobacterium tuberculosis has been associated with modification of the quinolone resistance determining region (QRDR) of gyrA. Recent studies suggest that amino acid substitutions in gyrB may also play a crucial role in resistance, but functional genetic studies of these mutations in M. tuberculosis are lacking. In this study, we examined twenty six mutations in gyrase genes gyrA (seven) and gyrB (nineteen) to determine the clinical relevance and role of these mutations in fluoroquinolone resistance. Transductants or clinical isolates harboring T80A, T80A+A90G, A90G, G247S and A384V gyrA mutations were susceptible to all fluoroquinolones tested. The A74S mutation conferred low-level resistance to moxifloxacin but susceptibility to ciprofloxacin, levofloxacin and ofloxacin, and the A74S+D94G double mutation conferred cross resistance to all the fluoroquinolones tested. Functional genetic analysis and structural modeling of gyrB suggest that M330I, V340L, R485C, D500A, D533A, A543T, A543V and T546M mutations are not sufficient to confer resistance as determined by agar proportion. Only three mutations, N538D, E540V and R485C+T539N, conferred resistance to all four fluoroquinolones in at least one genetic background. The D500H and D500N mutations conferred resistance only to levofloxacin and ofloxacin while N538K and E540D consistently conferred resistance to moxifloxacin only. Transductants and clinical isolates harboring T539N, T539P or N538T+T546M mutations exhibited low-level resistance to moxifloxacin only but not consistently. These findings indicate that certain mutations in gyrB confer fluoroquinolone resistance, but the level and pattern of resistance varies among the different mutations. The results from this study provide support for the inclusion of the QRDR of gyrB in molecular assays used to detect fluoroquinolone resistance in M. tuberculosis.     

Bismuth-Containing Quadruple Therapy as Second-Line Treatment for Helicobacter pylori Infection: Effect of Treatment Duration and Antibiotic Resistance on the Eradication Rate in Korea

Background:  The eradication rate of first-line Helicobacter pylori treatment is only 70–85% and has been decreasing due to the increase in antibiotic resistance. The aim of this study was to evaluate the efficacy of bismuth-containing quadruple therapy as second-line treatment for H. pylori infection based on treatment duration.
Methods:  We prospectively enrolled 227 patients that were found to have persistent H. pylori infection after first-line proton-pump inhibitor-clarithromycin-amoxicillin triple therapy. Patients were randomized to 1-week (112 patients) and 2-week (115 patients) quadruple therapy with tripotassium dicitrate bismuthate 300 mg q.i.d., meteronidazole 500 mg t.i.d., and tetracycline 500 mg q.i.d. and esomeprazole 20 mg b.i.d. The eradication rate, drug compliance, and adverse events were compared based on treatment duration.
Results:  The eradication rates were 72/112 (64.3%, 95% CI: 0.504–0.830) and 71/92 (77.2%, 0.440–0.749) with 1-week group, and 95/115 (82.6%, 1.165–2.449) an 88/94 (93.6%, 1.213–5.113) with 2-week group by intention-to-treat therapy ( p  = .002) and per-protocol analysis ( p  = .001), respectively. The adverse events increased as the treatment durations increased from 7 to 14 days (20.0 and 42.5%, respectively, p  < .001). However, there was no significant difference in the patient compliance or the rate of major adverse events between the 1- and 2-week groups (6.3 and 12.5%, respectively, p  = .133).
Conclusion:  Two-week bismuth-containing quadruple therapy was more effective than the 1-week treatment, and should be considered for second-line treatment in Korea.     

Gemifloxacin can partially overcome quinolone resistance of H. pylori with gyrA mutation in Taiwan

Backgrounds: The levofloxacin resistance caused by gyrA gene mutation is rising rapidly to limit wide application for Helicobacter pylori eradication. We investigated whether gemifloxacin has a superior antimicrobial activity to levofloxacin against H. pylori. Materials and Methods: Forty‐four consecutive clinical H. pylori isolates with levofloxacin resistance and 80 randomly selected levofloxacin‐sensitive controls were tested for gemifloxacin sensitivity by E‐test. The resistance to levofloxacin or gemifloxacin was defined as minimal inhibitory concentration (MIC) >1 mg/L. The clinical features and GyrA mutation patterns checked by direct sequencing were also analyzed to assess its association with the H. pylori gemifloxacin resistance. Results: All levofloxacin‐sensitive H. pylori isolates were sensitive to gemifloxacin. Eight strains (18.2%) resistant to levofloxacin could be still sensitive to gemifloxacin. Gemifloxacin achieved a 5‐time lower in MIC levels against levofloxacin‐resistant isolates. Nearly all levofloxacin‐resistant isolates (97.7%, 43/44) had GyrA mutation at amino acid position 87 or 91. Double mutation sites may play dual roles in quinolone resistance, as N87K plus H57Y or D91N plus V77A mutations showed high‐level resistance to both quinolones; whereas D91Y plus A97V or D91N plus A97V mutations showed low level levofloxacin resistance to become sensitive to gemifloxacin. In H. pylori isolates with single N87K, D91Y or D91N mutation, near 20% was gemifloxacin‐sensitive and levofloxacin‐resistant. The gemifloxacin‐resistant rate of H. pylori was higher in patients with gastric ulcer than in those without (p <.05). Conclusion: Gemifloxacin is superior to levofloxacin in antimicrobial activity against clinical H. pylori isolates, and even overcome some levofloxacin resistance.     

Long-term follow up of Helicobacter pylori IgG serology after eradication and reinfection rate of H. pylori in South Korea

Background: Serology is widely used for epidemiologic research of Helicobacter pylori . However, there is limited information on the long-term follow up of H. pylori titers after eradication. In addition, it is presumed that the reinfection rate decreases as the H. pylori infection rate decreases. The aim of this study was to investigate the long-term follow up of H. pylori IgG, and to evaluate the reinfection rate of H. pylori in Korea.
Methods: Among 247 patients, who were enrolled during 2003–07, 185 patients with invasive H. pylori test positive received proton pump inhibitor-based triple therapy, and follow-up H. pylori testing, including histology, CLOtest, culture, and serology, were evaluated 2, 10, and 18 months after H. pylori eradication.
Results: The initial H. pylori IgG optical density (OD_450nm), 2.06, gradually decreased to 0.63 (67% reduction) at 18 months after H. pylori eradication. The seroreversion rate was 5, 10, and 45% at 2, 10, and 18 months after H. pylori eradication, respectively. The recrudescence of H. pylori was 3.49%, and the annual reinfection rate was 2.94% per year. H. pylori IgG titers abruptly increased in cases with recrudescence and reinfection, and correlated with the results of the invasive H. pylori tests.
Conclusion: The results of this study showed that H. pylori IgG serology could be used for the determination of reinfection of H. pylori, but not for the diagnosis of H. pylori eradication. The reinfection rate of H. pylori , in Korea, was found to be very low, 2.94% per year.     

A "Screen-and-Treat" Approach for Helicobacter pylori Infection: A Population-Based Study in Vammala, Finland

Background:  To accelerate the decline of Helicobacter pylori infection, and to study the significance of the possible risk factors for H. pylori infection in Finland, we started a voluntary H. pylori "screen-treat-retest-and-retreat" program for all young adults at primary health care in Vammala, Finland after a pilot study in 1994 including 504 subjects aged 15–75.
Materials and Methods:  A total of 3326 aged 15–40 in 1996, and 716 aged 15 and 584 aged 45 in 1997–2000 were screened for H. pylori using serology. Helicobacter pylori positive were treated, cure was verified by serology.
Results:  The eradication rates were 93.8%, 82.2%, and 77.6% per protocol in pilot study in 1994, in subjects invited in 1996 and 1997–2000, respectively. Helicobacter pylori seroprevalence rates were calculated to have decreased from 36% to 14% in pilot study, from 12% to 4% among subjects invited in 1996, from 3% to 2% among subjects aged 15 and from 27% to 12% among subjects aged 45 in 1997–2000. An epidemiologic questionnaire in 1996 revealed that crowding in the childhood household, low education of the mother, current smoking and alcohol consumption, unfavorable housing conditions, and sick leaves due to dyspepsia were independently associated with H. pylori infection.
Conclusions:  This intervention with high participation rates resulted in a significant decline in calculated H. pylori seroprevalence rates. Although the low prevalence of H. pylori infection may limit the cost efficiency of the program, the intervention is expected to reduce the burden of H. pylori -associated diseases.     

Epidemiology of Helicobacter pylori Infection in Asymptomatic Children: A Prospective Population-Based Study from the Czech Republic. Application of a Monoclonal-Based Antigen-in-Stool Enzyme Immunoassay

Background:  Acquisition of Helicobacter pylori occurs mainly in childhood and is significantly influenced by geographical variations. The aim of this study is to evaluate the prevalence of H. pylori infection in a population-based sample of asymptomatic children in the Czech Republic. Furthermore, this study aims to identify potential risk factors associated with this infection.
Materials and Methods:  A prospective, cross-sectional, population-based study was undertaken in 1545 asymptomatic Czech children (aged 0–15 years; male 49.3%). Active H. pylori infection was diagnosed by monoclonal antibody-based antigen-in-stool enzyme immunoassay. Socio-demographic details of each subject were analyzed using a self-administered standardized questionnaire. Multiple regression analysis was performed.
Results:  Overall, 7.1% of asymptomatic children were diagnosed with H. pylori infection. Of the infected children, 5.8% lived in the general population. A positive association was found with increasing age, although not with gender. Independent risk factors associated with H. pylori infection in our pediatric population were: the number of children in a household (odds ratio [OR] 4.26; confidence interval [CI] 1.91–9.80); lack of formal education of fathers (OR 0.23; CI 0.18–0.64) and institutionalized children (OR 6.33; CI 2.25–26.50).
Conclusions:  This study of a large cohort of children demonstrated that, independent of gender, H. pylori infection in the Czech Republic is among the lowest reported in Europe. Socioeconomically disadvantaged children, unfortunately, are still at risk of harboring this potentially preventable infection in this low-prevalence region.     

Anti-Helicobacter pylori activity of Lactobacillus delbrueckii subsp. bulgaricus strains: preliminary report

Aims:  To evaluate the activities of six Lactobacillus delbrueckii subsp. bulgaricus (LB) strains against 30 Helicobacter pylori strains by agar-well diffusion method.
Methods and Results:  LB cultures [4 × 10⁸–4 × 10⁹ CFU ml⁻¹) either were prepared in milk at their native pH, 3·8–5·0, or were adjusted to pH 6·4–7·7. At low and neutralized pH, LB strains inhibited the growth by 40–86·7% and 16·7–66·7% of H. pylori strains, respectively. LB activity was strain-dependent. At low and neutralized pH, one and five H. pylori strains, respectively, were not inhibited by any LB strain. LB2 and LB3, taken together, were active against most metronidazole and clarithromycin resistant strains.
Conclusions:  All LB strains inhibited a number of H. pylori strains, including also antibiotic resistant strains. LB activity was strain-dependent and better at low pH. At low pH values, the most active LB strains were LB1, LB2 and LB3, inhibiting 86·7% of H. pylori strains, while at neutralized pH values, the most active LB strains were LB2 and LB3, inhibiting 53·3 and 66·7% of H. pylori strains, respectively.
Significance and Impact of the Study:  LB could be utilized in the treatment or prophylaxis of H. pylori infection and warrants clinical investigations.     

Genetic Variation in a4GnT in Relation to Helicobacter pylori Serology and Gastric Cancer Risk

Background:  Helicobacter pylori, a known risk factor of gastric cancer, rarely colonize the deeper portion of normal gastric glands, where the mucus is rich in α-1,4-linked N -acetylglucosamine capped O -glycans, that strongly inhibit H. pylori growth in vitro .
Materials and methods:  We investigated the association between genetic variation in the O -glycan transferase encoding gene ( a4GnT ) and H. pylori infection and gastric cancer risk using a Polish population-based case–control study (273 gastric cancer patients and 377 controls).
Results:  A haplotype at the rs2622694–rs397266 locus was associated with H. pylori infection, with the A-A haplotype associated with a higher risk compared with the most frequent G-G haplotype (odds ratio 2.30; 95% confidence interval 1.35–3.92). The association remained significant after correction for multiple tests (global p value: nominal 0.002, empirical 0.045). Neither this haplotype nor the tagSNPs were associated with overall gastric cancer risk.
Conclusion:  a4GnT genetic variation may be relevant to H. pylori infection, but not to gastric cancer risk.     

LTA 252GG and GA Genotypes are Associated with Diffuse-Type Noncardia Gastric Cancer Risk in the Japanese Population

Background:  There are limited numbers of reports on the association of lymphotoxin-alpha ( LTA ) genotypes with gastric cancer.
Methods:  A nested case–control study was carried out in the longitudinal cohort of atomic bomb survivors using stored sera before diagnosis (mean, 2.3 years) and blood cells. Enrolled were 287 cases with noncardia gastric cancer of diffuse and intestinal types and three controls per case selected from cohort members matched on age, gender, city, and time and type of serum storage and counter-matched on radiation dose.
Results:  LTA 252GG and GA genotypes were associated with the prevalence of Helicobacter pylori IgG seropositivity and higher antibody titer against H. pylori cytotoxin-associated gene A (CagA) protein in controls and they were an independent risk factor for noncardia gastric cancer of diffuse type (RR = 2.8 (95% CI: 1.3–6.3), p  =   .01, and RR = 2.7 (95% CI: 1.5–4.8), p  <   .001), but not for intestinal type, after adjusting for H. pylori IgG seropositivity, CagA antibody titers, chronic atrophic gastritis, smoking, and radiation dose. Cessation of smoking (RR = 0.4 (95% CI: 0.2–0.7), p  <   .001) and never smoking (RR = 0.4 (95% CI: 0.3–0.6), p  <   .001) were both protective for future noncardia gastric cancer. Radiation dose was associated with noncardia gastric cancer in subjects with both the LTA 252G -allele and never smoking/quit smoking histories (RR = 3.8 (95% CI: 1.7–5.9), p  =   .009).
Conclusion:  The LTA 252 genotype is associated with noncardia gastric cancer of diffuse type in Japan and interacted with radiation dose.     

Childhood Hygienic Practice and Family Education Status Determine the Prevalence of Helicobacter pylori Infection in Iran

Background: Management of Helicobacter pylori , a causative agent of gastrointestinal diseases is an important health problem in most countries. The main reasons include poorly defined epidemiological status and unrecognized mode of bacterial transmission. Our objective was to investigate the prevalence of H. pylori infection in a representative population of Iran and to evaluate possible risk factors for the H. pylori infection.
Materials and methods: In this cross-sectional study, 2561 healthy individuals aged 18–65 years (mean age, 35.5 years) were selected out of 12,100,000 inhabitants of Tehran province by cluster sampling. Infection with H. pylori was evaluated by detection of anti- H. pylori IgG antibody in serum. Sociodemographic status of each subject was determined by filling up a questionnaire.
Results: Prevalence of H. pylori infection was 69% and was correlated with increasing age. The highest infection rate (79.2%) was seen in individuals 46–55 years old. No association was detected between H. pylori positivity and gender. Low education of the study subjects; low father's and mother's education; poor tooth brushing habit; crowded families in childhood; and lack of household bath, hygienic drinking water, and swage disposal facility in childhood were determined as possible risk factors.
Conclusions: The rate of prevalence of H. pylori infection was higher than developed countries. Low socioeconomic status, poor sanitary indications, and crowded families in childhood were related to high prevalence of H. pylori infection in Iran. Accordingly, fecal–oral and oral–oral routes could be considered as the main pathways of transmission of H. pylori .