Epidemiology of Helicobacter pylori infection

Clarithromycin-based Helicobacter pylori eradication therapy is not associated with higher treatment failure compared with non-clarithromycin-based regimens in a tertiary referral hospital in Switzerland

BACKGROUND AND AIMS

Due to increasing antibiotic resistance, various Helicobacter pylori eradication regimens other than clarithromycin-based therapies have been proposed. However, detailed data on which therapies were employed and their eradication success is lacking. The purpose of this study was to analyse the response rates of different eradication therapy schemes.

METHODS

In this retrospective cohort study, we analysed data of 1721 patients and included 608 patients undergoing H. pylori eradication therapy at the Department of Gastroenterology at the University Hospital Zurich between 2004 and 2018. The primary endpoint was the success rates of clarithromycin- and non-clarithromycin-containing H. pylori eradication regimens. We furthermore analysed factors with potential impact on the outcome of H. pylori eradication therapies, such as demographics, and smoking and social status.

RESULTS

The most common therapy scheme (71% of all cases) was proton pump inhibitor (PPI)-amoxicillin-metronidazole, followed by PPI-amoxicillin-clarithromycin (21%) and PPI-metronidazole-clarithromycin (6%). There was no difference between the H. pylori eradication success of clarithromycin vs non-clarithromycin-containing therapies (71% vs 71%, p = 0.764).

CONCLUSION

Despite increasing clarithromycin resistance globally, there was no difference in the eradication success of clarithromycin- and non-clarithromycin-containing therapy regimens in Switzerland. As varying triple therapies do not increase eradication rates in real-world settings, other primary therapy options such as quadruple therapies should be explored.

Management of H. pylori Induced Peptic ulcer – A Phytotherapeutic Approach

A peptic ulcer is a chronic infectious disease that creates erosion on the epithelial lining of the stomach. It is a commonly encountered problem in the gastrointestinal tract (GI tract). Patients failed multiple regimens due to resistant H. pylori infection. H. pylori show maximum resistance towards Clarithromycin. Due to the consistent increase in resistance there is urgent need for the development of new drugs. Paying much for the antibiotic treatment one should go for the natural treatments with no side effects. Modern treatment of peptic ulcers emphasizes diet with routinely recommend hospitalization of several weeks. Currently, a lot of medications are coming out of natural products. The phytotherapeutic approach for the resistant H.pylori treatment is assessed. The plant produces many secondary metabolic substances which have a lot of beneficial roles in maintaining human health. Administration of plant products would prevent disease and able to eradicate resistant H.pylori. This review includes many phytoproducts having a wide range of antimicrobial activity. Reviewed phytoproducts includes Phytoceutical, Caffeic acid, phenethyl ester, Flavonoid, Capsaicin, Carotenoid, etc are effective treatment against H.pylori. To see their effect on the resistant H.pylori and to manage this resistant bacteria with an application of plant products is the prime concern of this review. The linkage between phytochemical and peptic ulcers will provide a novel framework for the future.

Effect of major CYP2C19 genetic polymorphisms on Helicobacter pylori eradication based on different treatment regimens

Helicobacter pylori (H. pylori) infection is a global issue. Its eradication in affected individuals is important to prevent several further complications that may occur if left untreated. Proton pump inhibitors (PPIs) serve an important role in the eradication regimens of H. pylori. PPIs are metabolized primarily through the CYP2C19 enzyme in the liver. Inter-individual variation in the response to eradication treatment may partly be due to variations in the metabolism of PPIs. The aim of this study was to determine whether there was any association between CYP2C19 genetic polymorphisms and the response to eradication therapy amongst Jordanians infected with H. pylori receiving lansoprazole-based regimens. The present study was approved by the Institutional Review Board of The University of Jordan Hospital. A total of 141 patients infected with H. pylori were genotyped for the polymorphisms CYP2C19^*2 and CYP2C19^*17 using the PCR-restriction fragment length polymorphism assay method. Patients received lansoprazole-based triple or sequential therapy. The assessment of eradication was performed using either a H. pylori stool antigen test or from feedback from patients regarding their improvement. Eradication rates were 84.6% and 64.5% in the intermediate-metabolizer and extensive-metabolizer group, respectively. This difference was not statistically significant. Moreover, no significant association was found between the carriers of the CYP2C19^*17 polymorphism and the response to eradication therapy. These findings suggest that there was no significant association between the CYP2C19 genotype and the response to eradication therapy amongst Jordanians infected with H. pylori.

Changes in the Seroprevalence of Helicobacter pylori among the Lithuanian Medical Students over the Last 25 Years and Its Relation to Dyspeptic Symptoms

Background and Objectives: The prevalence of Helicobacter pylori infection is decreasing in the Western world, while remaining high in developing countries. There is limited up-to-date information about the prevalence of H. pylori in Central and Eastern Europe. The aim of our study was to assess the seroprevalence of H. pylori and its trend over the past 25 years among students of the Lithuanian University of Health Sciences (LUHS) and to assess its relation to dyspeptic symptoms. Materials and Methods: In the years 1995, 2012, 2016 and 2020, students from Medical and Nursing Faculties of LUHS were tested for the presence of antibodies against H. pylori by performing serological tests from finger capillary blood. In addition, in the years 2012, 2016 and 2020, the students completed a gastrointestinal symptom rating scale (GSRS) questionnaire in order to assess dyspeptic symptoms. The study population consisted of 120 students in the year 1995 (mean age—21.3 ± 1.0 years), 187 students in the year 2012 (mean age—22.4 ± 0.7 years), 262 students in the year 2016 (mean age—20.4 ± 1.0 years) and 148 students in the year 2020 (mean age—20.4 ± 1.7 years). Results: The seroprevalence for H. pylori was positive in 62 (51.7%) students in 1995, in 57 (30.4%) students in 2012, in 69 (26.3%) students in 2016 and in 21 (14.2%) students in 2020. The statistically significant difference was found between all study years, except between 2012 and 2016. There were no significant differences in frequency and intensity of upper dyspeptic symptoms between H. pylori positive and negative students. Conclusions: Over the last 25 years the seroprevalence of H. pylori among students of LUHS has decreased significantly. No consistent differences in dyspeptic symptoms among H. pylori positive and negative subgroups were found.

Evaluation of Helicobacter pylori Infection and Clarithromycin Resistance in Strains From Symptomatic Colombian Children

The aim of the study was to determine the current prevalence of Helicobacter pylori in symptomatic Colombian children and evaluate the presence of mutations associated with clarithromycin resistance. Biopsies from 133 children were analyzed. The gastric fragment was used for urease test and reused for polymerase chain reaction sequencing of the 23SrDNA gene. Mutations were detected by bioinformatic analysis. Polymerase chain reaction sequencing established that H pylori infection was present in 47% of patients. Bioinformatics analysis of the 62 positive sequences for 23SrDNA revealed that 92% exhibited a genotype susceptible to clarithromycin, whereas the remaining strains (8%) showed mutations associated with clarithromycin resistance. The low rate of resistance to clarithromycin (8%) suggests that conventional treatment methods are an appropriate choice for children. Recycling a biopsy that is normally discarded reduces the risks associated with the procedure. The 23SrDNA gene amplification could be used for a dual purpose: detection of H pylori and determination of susceptibility to clarithromycin.

Houston Consensus Conference on Testing for Helicobacter pylori Infection in the United States

Despite guidelines for detection and treatment of Helicobacter pylori infection, recommendations to test patients before and after therapy are commonly not followed in the United States. At the Houston Consensus Conference, 11 experts on management of adult and pediatric patients with H pylori, from different geographic regions of the United States, met to discuss key factors in diagnosis of H pylori infection, including identification of appropriate patients for testing, effects of antibiotic susceptibility on testing and treatment, appropriate methods for confirmation of infection and eradication, and relevant health system considerations. The experts divided into groups that used a modified Delphi panel approach to assess appropriate patients for testing, testing for antibiotic susceptibility and treatment, and test methods and confirmation of eradication. The quality of evidence and strength of recommendations were evaluated using the GRADE system. The results of the individual workshops were presented for a final consensus vote by all panel members. After the Expert Consensus Development meeting, the conclusions were validated by a separate panel of gastroenterologists, who assessed their level of agreement with each of the 29 statements developed at the Expert Consensus Development. The final recommendations are provided, on the basis of the best available evidence, and provide consensus statements with supporting literature to implement testing for H pylori infection at health care systems across the United States.

Association of hp1181 and hp1184 Genes With the Active Efflux Phenotype in Multidrug-Resistant Isolates of Helicobacter pylori

Background

During the last decades the rate of multidrug resistance among clinical Helicobacter pylori isolates has increased. Active pumping out of the drugs may be an important mechanism for multidrug resistance in H. pylori strains.

Objectives

The aim of this study was to evaluate the association of two H. pylori efflux-genes, hp1181 and hp1184 with the active-efflux phenotype in MDR clinical-strains of H. pylori.

Materials and Methods

Minimal inhibitory concentration (MIC) and drug accumulation for β-lactames, Tetracycline (TET), Erythromycin (ERY), Metronidazole (MTZ), Ciprofloxacin (CIP) and Ethidium Bromide (EtBr) was performed in the presence and absence of carbonyl cyanide M-Chlorophenyl Hydrazone (CCCP). Presence of hp1181 and hp1184 genes was detected by the polymerase chain reaction (PCR). RT-PCR was performed to compare expression of efflux genes by MDR strains, demonstrating active efflux with the strains without active efflux.

Results

Two- to four-fold decrease in minimum inhibitory concentration (MIC) and two-fold increase in accumulation were observed for EtBr in the presence of CCCP for 67% (8) of 12 MDR strains. With CCCP, two- to four-fold decrease in MIC and 1.4- to 1.8-fold increase in the accumulation of β-lactames, TET, CIP and MTZ were obtained for 42% (5) of the MDR strains. Six, five and three of the 12 MDR strains amplified hp1184, hp1181, and both of them, respectively. The RT-PCR product for expression of hp1181 by MDR strains was approximately 100 bp shorter than that of the 26695 susceptible standard strain.

Conclusions

Expression of the genes hp1184 and hp1181 are associated with the specific active efflux of EtBr and non-related antibiotics, respectively. For displaying these phenotypes, a post-transcriptional regulation step may be required.

High Frequency of vacA s1m2 Genotypes Among Helicobacter pylori Isolates From Patients With Gastroduodenal Disorders in Kermanshah, Iran

Background:

Helicobacter pylori infection and related diseases outcome are mediated by a complex interplay between bacterial, host and environmental factors. Several distinct virulence factors of H. pylori have been shown to be associated with different clinical outcomes. Here we focused on vacA and cagA genotypes of H. pylori strains isolated from patients with gastric disorder.

Objectives:

The aim of this study was to determine the frequency of two toxins and genotypes of VacA toxin in patients referred to a central hospital in the west of Iran (Imam Reza hospital, Kermanshah) during 2011 - 2012.

Patients and Methods:

Samples were collected from patients infected with H. pylori. Gastric biopsy specimens from the stomach antrum and corpus were cultured. PCR analysis was performed for genotyping H. pylorivacA and cagA genes.

Results:

Helicobacter pylori was isolated from 48% (96/200) of patients with gastroduodenal disorders. In 81/96 (84%) cases, the cagA gene was present. Among different genotypes of vacA, two s1m2 and s2m2 genotypes were dominant with frequency of 39.5% and 50%, respectively. The frequency of the s1m1 genotype was 7.2% (7/96), which is much lower than elsewhere. H. pylori isolates with positive results for cagA gene and vacA s1m2 genotypes showed statistically significant correlation with peptic ulcer (s1m2 13/34 [38.2%] P = 0.003). However, isolates of H. pylori infection with cagA gene and vacAs2m2 genotypes were significantly associated with development of gastritis (s2m2 41/42 [97.6%] P = 0.000).

Conclusions:

About 90% of H. pylori strains potentially contained vacAs2m2 and s1m2 genotypes. Infection with H. pylori strain containing the cagA gene or the vacAs1m1 and s1m2 genotypes was associated with increased incidence of peptic ulcer disease (PUD).

Correlation of serology with morphological changes in gastric biopsy in Helicobacter pylori infection and evaluation of immunohistochemistry for H. pylori identification

BACKGROUND/AIM

Helicobacter pylori is implicated in various gastroduodenal diseases and many tests are available for its detection. The present study attempted to document the morphological changes in the gastric mucosa induced by H. pylori colonization and correlate them with the severity of the infection. The study also compared various diagnostic tests and evaluated the different staining methods used for H. pylori detection, especially immunohistochemical identification.

PATIENTS AND METHODS

One hundred and two patients with dyspepsia were included. Enzyme-linked immunosorbent assay (ELISA) for H. pylori-specific immunoglobulin G (IgG), immunoglobulin A (IgA), and immunoglobulin M (IgM) was used. Rapid urease test was performed on endoscopic biopsy and it was stained with hematoxylin and eosin (H and E), modified Giemsa, and immunohistochemical stains.

RESULTS

A significant correlation was found between the density of H. pylori and severity of gastritis. A significant correlation was observed between serology (especially when used in combination, IgG and IgA) and status of H. pylori. Immunohistochemical staining enhanced the diagnostic yield of H. pylori detection.

CONCLUSIONS

Immunohistochemistry (IHC) should be used judiciously, whereas simple and economical tests like modified Giemsa should be used routinely for the detection of H. pylori. Combined ELISA (IgG and IgA) should be preferred over single ELISA. Simultaneous morphological and serological detection of H. pylori is preferable as H. pylori may not be detected on morphology alone due to its patchy distribution in the stomach.

Dried blood spot samples for seroepidemiology of infections with human papillomaviruses, Helicobacter pylori, Hepatitis C Virus, and JC Virus

BACKGROUND

To establish antibody analysis from dried blood spots (DBS) on filter paper for seroepidemiologic infection and cancer association studies, we analyzed data from a population-based study in Mongolia.

METHODS

Using multiplex serology, we analyzed 985 paired DBS and serum samples from the same donors for antibodies to 12 different proteins from four groups of infectious agents: human papillomaviruses (HPV), Helicobacter pylori (H. pylori), hepatitis C virus (HCV), and JC polyomavirus (JCV).

RESULTS

Quantitative antibody reactivities in serum and DBS showed good correlation, with median correlation coefficients (Pearson R(2)) of 0.88 (range, 0.80-0.90) for high-titer (i.e., H. pylori, HCV, JCV) and 0.79 (range, 0.72-0.85) for low-titer antibodies (i.e., HPV). For high-titer antibodies, serum and DBS data were comparable (median slope of linear trend line, 1.14; range, 1.09-1.21), whereas for low-titer antibodies, DBS reactivities were lower than in serum (median slope, 0.54; range, 0.50-0.80). By extrapolating seropositivity cutoff points previously defined for serum to DBS, we found high agreement (>89% for all antigens) of dichotomized DBS and serum results and median kappa values for high- and low-titer antibodies of 0.86 and 0.78 (range, 0.78-0.92 and 0.55-0.86), respectively. Epidemiologic associations with known risk factors for HPV antibodies were as strong for DBS as for serum.

CONCLUSIONS

DBS provide a reliable alternative to serum or plasma for detection of antibodies against various pathogens by multiplex serology.

IMPACT

DBS do not require blood centrifugation and allow storage and shipment at ambient temperature, thus facilitating field work for seroepidemiologic studies especially in environments with limited technical infrastructure.

Anti-Helicobacter pylori activity of fermented milk with lactic acid bacteria

BACKGROUND

Ten strains of lactic acid bacteria (LAB) were investigated for their anti-Helicobacter pylori effects. The bactericidal activity and organic acid content in spent culture supernatants (SCS) from fermented milk were measured. In addition, the exclusion effect of SCS against H. pylori infection of human gastric epithelial AGS cells was assayed.

RESULTS

Three LAB strains, LY1, LY5 and IF22, showed better anti-Helicobacter effects than the other strains. There were no significant differences in the bactericidal activity of LAB strains between original SCS, artificial SCS and SCS treated by heating or protease digestion. However, neutralised SCS lost this activity. These results suggest that the anti-H. pylori activity of SCS may be related to the concentration of organic acids and the pH value but not to protein components. In the AGS cell culture test, both fermented LY5-SCS and artificial LY5-SCS significantly reduced H. pylori infection and urease activity (P < 0.05).

CONCLUSION

In this study, in vitro methods were used to screen potential probiotics with anti-H. pylori activity. This may provide an excellent and rapid system for studying probiotics in the functional food and dairy industries.

H. pylori seropositivity before age 40 and subsequent risk of stomach cancer: a glimpse of the true relationship?

Stomach carcinogenesis involves mucosal and luminal changes that favor spontaneous disappearance of Helicobacter pylori. Therefore, the association between the infection and cancer risk might typically be underestimated. As acquisition of the infection almost invariably occurs before adulthood, the serostatus at age 16–40 should best reflect the lifetime occurrence of the infection. We therefore conducted a case-control study nested within a historic cohort of about 400,000 individuals who donated sera before age 40 to either of two large Swedish Biobanks between 1968 and 2006, and whose records were linked to complete nationwide registers. For each stomach adenocarcinoma case occurring at least 5 years after serum donation 2 controls were selected matched on age, sex and year of donation and biobank. Serum immunoglobulin G antibodies against H. pylori cell-surface antigens (Hp-CSAs) were measured with an enzyme–linked immunosorbent assay and antibodies against CagA with an immunoblot assay. Conditional logistic regression models were used to estimate odds ratios (ORs) for stomach adenocarcinoma among H. pylori infected relative to uninfected. We confirmed 59 incident cases of stomach adenocarcinoma (41 non-cardia tumors) during follow-up. ORs for non-cardia stomach adenocarcinoma among subjects with Hp-CSA antibodies (regardless of CagA serostatus), antibodies against CagA (regardless of Hp-CSA serostatus), and antibodies to both, relative to those who were seronegative to both, were 17.1 (95% confidence interval [CI] 4.0–72.9), 10.9 (95% CI 3.2–36.9), and 48.5 (95% CI 5.8–407.4), respectively. H. pylori infection is a much stronger risk factor for non-cardia stomach adenocarcinoma than initially realized. However, further studies are needed to answer whether it is a necessary cause, as the possibility of misclassification of H. pylori status could not be ruled out in our study.

14C-urea breath test is safe for pediatric patients

Helicobacter pylori (H. pylori) infection, quite prevalent in the developing countries, is considered to be one of the causative factors for various gastric pathologies and other nongastric diseases. It is believed that H. pylori infection is almost always acquired in early childhood and persists throughout life unless specific treatment is given. The (13/14)C-urea breath test (UBT) is now considered to be a 'gold standard' technique for the detection of H. pylori infection. However, because of the lack of facilities and high cost, the preferred nonradioactive ¹³C-UBT cannot be performed on pediatric patients in developing countries, whereas the radioactive ¹⁴C-UBT is not used on children because of the fear of radiation exposure. When using 37 kBq (1 μCi) of ¹⁴C-urea for the ¹⁴C-UBT, the patient is not exposed to more radiation than is acquired from the natural environment in one day, as almost all the ingested radioactivity is excreted from the body (urine and breath) within 72-120 h. This article reviews the importance of the ¹⁴C-UBT for the detection of H. pylori and justifies the radiation safety aspects of its use in children without any fear of 'radiation phobia' where the facility for ¹³C-UBT is lacking.

Helicobacter pylori: prevalence and relationship with abdominal pain in school children in Makkah City, western Saudi Arabia

BACKGROUND/AIM

The published data on Helicobacter pylori (H. pylori) prevalence and its relationship with abdominal pain in Saudi Arabia is scarce. This study was carried out to determine the prevalence of H. pylori and its relationship with chronic recurrent abdominal pain (RAP) among school students in Makkah City, Saudi Arabia.

MATERIALS AND METHODS

Three hundred and fourteen school students, 103 at the intermediate level (grades 7-9) aged 12-15 years and 211 at the secondary level (grades 10-12) aged 15-18 years were tested for H. pylori. Urea breath test (UBT) was used for this purpose. Children with chronic RAP were identified as per the Apley criteria.

RESULTS

Overall, the UBT was positive in 86/314 (27.4%) students. It was positive in 45/103 (43.7%) intermediate school students and 41/211 (19.4%) secondary students. Out of the 55 students with chronic RAP, 40 (73%) were positive for H. pylori. Further, 62.9% and 82.1% were positive among the intermediate and secondary school students with RAP, respectively. The overall and specific odds ratios of RAP were 12.35 [95% confidence interval (C.I.) 6.30-24.22] and 10.40 (95% C.I. 1.75-11.73) for the intermediate school students and 22.69 (95% C.I. 7.99-64.44) for the secondary school students.

CONCLUSION

The prevalence of H. pylori among the school children in Makkah, Saudi Arabia, is relatively low compared with developing countries. The prevalence was found to be higher among the younger age group. Further, there was a significant relation between H. pylori infection and RAP among the school students.

Cost-effectiveness of a potential future Helicobacter pylori vaccine in the Netherlands: the impact of varying the discount rate for health

To estimate the cost-effectiveness of a potential Helicobacter pylori (HP) vaccine for the Dutch situation, we developed a Markov model. Several HP prevalence scenarios were assessed. Additionally, we assessed the impact of the discount rate for health on the outcomes, as this influence can be profound for vaccines. When applying the current discount rate of 1.5% for health, the expected cost-effectiveness of HP vaccination is estimated below the informal Dutch threshold of euro 20,000/LYG when the HP prevalence is assumed > or =20% in the Dutch population. In conclusion, we showed that HP vaccination could possibly be a cost-effective intervention. However, this depends to a large extend on the prevalence of HP in the population. Furthermore, we showed the large impact of the discount rate for health on the cost-effectiveness of a HP vaccination program, illustrative for other vaccination programs.

Prevalence and risk factors for Helicobacter pylori infection in Chinese populations

BACKGROUND

The prevalence of Helicobacter pylori is higher in developing countries. The aim of this study was to investigate the prevalence and risk factors of H. pylori infection in areas with high prevalence of gastric cancer in Jiangsu Province, China.

METHODS

A prospective epidemiologic survey of H. pylori infection was accomplished in a natural population of 1457 individuals in Xiangshui and Gaoyou counties, Jiangsu Province, China. Questionnaires and laboratory tests for H. pylori infection ((13)C-urea breath test and serum IgG antibodies to H. pylori) were used and performed, respectively.

RESULT

Among 1371 subjects who completed questionnaires and H. pylori detection, 851 (62%) were H. pylori positive. The prevalence reached a peak at the age of 30-40 years (67%). There was no sex difference. The annual family income level was shown to be positively correlated with the risk of H. pylori infection. The prevalence of H. pylori infection was also associated with family size, education level, and several diet-related factors, such as the number of times cooked rice and potatoes eaten per week, and a family history of stomach diseases. Compared to nonsymptomatic individuals, people with dyspeptic symptoms (nausea, vomiting, and belching) presented a low prevalence of H. pylori infection. No association between H. pylori prevalence and smoking or drinking was found. Using multivariate logistic regression analysis, annual family income and education level were the independent predictors for H. pylori infection.

CONCLUSION

High prevalence of H. pylori infection was found in areas with a high risk of gastric cancer and was related to several risk factors. The underlying mechanisms need to be further investigated.

Serum pepsinogen levels, Helicobacter pylori CagA Status, and cytokine gene polymorphisms associated with gastric premalignant lesions in Costa Rica

The detection of gastric premalignant lesions, atrophic gastritis, corpus atrophic gastritis, and intestinal metaplasia, using several potential markers was examined in Costa Rica. Depending on the lesion investigated, from a total of 223 dyspeptic patients, 58 (26.0%), 31 (13.9%), or 23 (10.3%) were histologically diagnosed with atrophic gastritis, corpus atrophic gastritis, or intestinal metaplasia, respectively. Sera were used for the measurement of pepsinogen (PG) and Helicobacter pylori CagA antibody (CagA-ab) levels by ELISA, and human genomic DNAs were used for the genotyping of interleukin (IL)-1beta (-511 and +3954), IL-10 (-1082 and -592), and IL-1RN intron 2 by PCR and RFLP. Multivariate analysis was done adjusting for sex, age, and H. pylori seropositivity. Low PG levels (L-PG; PG I < or = 70 microg/L + PG I/II < or = 3), very low PG levels (VL-PG; PG I < or = 30 microg/L + PG I/II < or = 2), and CagA-ab were individually associated with all premalignant lesions whereas IL-1beta +3954T-carrier and IL-1RN homozygous 2 allele were associated with intestinal metaplasia. VL-PG, for corpus atrophic gastritis detection, was the single marker with the highest combination of test characteristics, sensitivity (77.4%), specificity (80.7%), positive predictive value (39.3%), negative predictive value (95.7%), and seropositivity rate (27.4%), expected to improve after periodic measurements. Combined examinations of VL-PG and CagA-ab improved the specificity (92.7%) and positive predictive value (62.2%), with similar sensitivity (74.2%) and negative predictive value (95.7%). In conclusion, corpus atrophic gastritis detection with periodic measurements of serum PG, alone or in combination with CagA-ab status, to identify high gastric cancer risk, seems to be the method best suited for mass screening in Costa Rica.

Phenylphosphonate transport by Helicobacter pylori

BACKGROUND

Helicobacter pylori can utilize phenylphosphonate as a sole source of phosphorus, and it is able to transport the phosphonate N-phosphonoacetyl-L-aspartate. However, H. pylori does not have any genes homologous to those of the known pathways for phosphonate degradation in bacteria, indicating that it must have novel pathways for the transport and metabolism of phosphonates.

METHODS

Phenylphosphonate transport by H. pylori was studied in strains LC20, J99 and N6 by the centrifugation through oil method using [(14)C]-labeled phenylphosphonate.

RESULTS

The Michaelis constants of transport K(t) and V(max) for phenylphosphonate showed similar kinetics in the three strains. The Arrhenius plot for phenylphosphonate transport rates at permeant concentrations of 50 micromol/L was linear over the temperature range 10-40 degrees C with an activation energy of 3.5 kJ/mol, and a breakpoint between 5 and 10 degrees C. Transport rates increased with monovalent cation size. The effects of various inhibitors were investigated: iodoacetamide, amiloride, valinomycin, and nigericin reduced the rate of phenylphosphonate transport; sodium azide and sodium cyanide increased the transport rate; and monensin had no effect.

CONCLUSIONS

The kinetics and properties of H. pylori phenylphosphonate transport were characterized, and the data suggested a carrier-mediated transport mechanism.

[Comparison of three diagnostic methods to confirm Helicobacter pylori infection]

INTRODUCTION

Helicobacterpylori induces gastric inflammation in host and such gastritis increases the risk of gastric and duodenal ulceration as well as adenocarcinoma. Because peptic ulcer disease is the major cause of morbidity, accurate diagnosis of H. pylori infection is very important. Unfortunately, there is no gold standard among diagnostic tests for Helicobacter infections. If gastroscopy is performed, histopathology and urease test are the most often used. Still, culturing of this bacterium is essential for drug susceptibility testing and analysis of virulence factors.

OBJECTIVE

The aim of this study was to compare three diagnostic procedures--histopathology, urease test and culture, which are used to verify H. pylori infection.

METHOD

Three pairs of gastric mucosal biopsy specimens were collected from each of 28 dyspeptic patients undergoing endoscopy. Nineteen patients were not pretreated with antibiotics, while nine had received eradication therapy earlier. One pair of biopsy specimens was used for histopathologic examination, the second for urease test and the third was simultaneously cultured on nonselective and selective solid media. Isolate was identified as H. pylori on the basis of colony morphology, morphological properties and biochemical tests.

RESULTS

In 14 out of 28 patients, H. pylori infection was confirmed on the basis of results of all diagnostic procedures. The concordance of these three methods was very good, because the results of histopathology, urease test and culture corresponded in 26 from 28 patients.

CONCLUSION

The conclusion of our study is that culture, as the method with high degree of concordance with other two procedures and the only that can give information on drug susceptibility of Helicobacter, is recommended for diagnosis of Helicobacter pylori infection along with histopathology and urease test.

Low prevalence of Helicobacter pylori infection in young children in the Netherlands

AIM OF THE STUDY

To investigate the seroprevalence of Helicobacter pylori infection in young children from the general population in The Netherlands.

METHODS

Determination of IgG antibodies against H. pylori, using an enzyme-linked immunosorbent assay technique [cutoff 0.32 Absorption Index (AI)], in serum from 1258 children who were 2-4 years of age. The serum was obtained from a serum bank of 6127 children who attended the community child healthcare centers in the Dutch province of Zuid-Holland.

RESULTS

In general, we found a seroprevalence of 1.2% of H. pylori infection, with a significant difference between the children with parents who were both Dutch (0.5%), and the children with at least one non-Dutch parent (2.6%) (P<0.001).

CONCLUSIONS

The prevalence of H. pylori infection in young infants in the general population in The Netherlands is low. Children with at least one non-Dutch parent form a risk group, however, for H. pylori infection in The Netherlands.

Socioeconomic position and the risk of gastric and oesophageal cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC-EURGAST)

OBJECTIVES

To evaluate the association of socioeconomic position with adenocarcinoma of the oesophagus and stomach.

METHODS

The European Prospective Investigation into Cancer and Nutrition (EPIC) cohort comprises about 520 000 participants mostly aged 35-70 years. Information on diet and lifestyle was collected at recruitment. After an average follow-up of 6.5 years, 268 cases with adenocarcinoma of the stomach and 56 of the oesophagus were confirmed. We examined the effect of socioeconomic position on cancer risk by means of educational data and a computed Relative Index of Inequality (RII). In a nested case-control study, adjustment for Helicobacter pylori (H. pylori) infection was performed.

RESULTS

Higher education was significantly associated with a reduced risk of gastric cancer [vs lowest level of education, hazard ratio (HR): 0.64, 95% Confidence intervals (CI): 0.43-0.98]. This effect was more pronounced for cancer of the cardia (HR: 0.42, 95% CI: 0.20-0.89) as compared to non-cardia gastric cancer (HR: 0.66, 95% CI: 0.36-1.22). Additionally, the inverse association of educational level and gastric cancer was stronger for cases with intestinal (extreme categories, HR: 0.13, 95% CI: 0.04-0.44) rather than diffuse histological subtype (extreme categories, HR: 0.71 95% CI: 0.37-1.40). In the nested case-control study, inverse but statistically non-significant associations were found after additional adjustment for H. pylori infection [highest vs lowest level of education: Odds ratio (OR) 0.53, 95% CI: 0.24-1.18]. Educational level was non-significantly, inversely associated with carcinoma of the oesophagus.

CONCLUSION

A higher socioeconomic position was associated with a reduced risk of gastric adenocarcinoma, which was strongest for cardia cancer or intestinal histological subtype, suggesting different risk profiles according to educational level. These effects appear to be explained only partially by established risk factors.

Progression of atrophic gastritis and intestinal metaplasia drives Helicobacter pylori out of the gastric mucosa

This study was performed to evaluate the implication of anti-H. pylori IgG positivity when CLOtest, histological test, and culture in the antrum and body are all negative, and to find out the specific disease category that is more affected by the hostile relationship of atrophic gastritis and intestinal metaplasia (IM) with H. pylori. Four hundred thirty-six patients (84 controls, 69 with duodenal ulcer, 96 with benign gastric ulcer, 43 with dysplasia, 144 with gastric cancer), who had not received any eradication therapy, were divided into three groups according to H. pylori test: CLOtest or histological H. pylori-positive group (group A; 294 cases), only anti-H. pylori IgG-positive group (group B; 62 cases), and anti-H. pylori IgG-negative group (group C; 80 cases). The grade of neutrophil and monocyte infiltration, atrophic gastritis, and IM was compared according to the updated Sydney system classification. Neutrophil and monocyte infiltrations were significantly severe in the group A. In contrast, the grade of atrophic gastritis and IM in the antrum was significantly higher in group B than the other two groups, A or C. When patients were divided according to the disease outcome in each group, the grade of IM in the body was statistically higher only in the patients with cancer or dysplasia in group B. These results suggest that anti-H. pylori IgG positivity with all negative invasive H. pylori tests represents past infection with H. pylori rather than a false negative, especially in the case of dysplasia and gastric cancer.

In vitrogrowth inhibition ofHelicobacter pyloriby lactobacilli belonging to theLactobacillus plantarumgroup

AIMS

The aim of this study was to test and locate the in vitro anti-Helicobacter activity of seven Lactobacillus strains belonging to Lactobacillus plantarum group.

METHODS AND RESULTS

Growth inhibition of H. pylori was tested using a well-plate assay. Of the strains displaying the strongest growth inhibition, a L. plantarum isolated from sauerkraut (MLBPL1) was chosen for further studies. The detected anti-Helicobacter activity of MLBPL1 was mainly associated with cell wall, and to a minor extent with the culture supernatant. The active component, which was determined to be between 3 and 10 kDa in size, retained its activity after 10 min treatment at 100 degrees C. The activity was present when MLBPL1 was cultivated in rich laboratory cultivation medium MRS and in different food matrices.

CONCLUSIONS

The strains belonging to L. plantarum group showed anti-Helicobacter activity in vitro. The main activity seemed to be associated with cell wall rather than culture supernatant or intracellular fraction.

SIGNIFICANCE AND IMPACT OF THE STUDY

In view of the rapid spread of resistant H. pylori strains caused by antibiotic therapy, addition of a fermented food containing L. plantarum to the conventional antibiotic treatment of Helicobacter infection could establish a potential complementary means to suppress the infection.

A seroepidemiology survey on Helicobacter pylori infection in rural families

AIM: To estimate the prevalence of H. pylori infection in rural families, and to investigate the transmission route of H. pyloriinfection.

METHODS: A cross-sectional study was carried out among 263 villagers from 71 families in September 2004 in Zunhua city, Hebei province. Each subject was interviewed using a unified questionnaire. Blood sample of 5 mL was collected for the antibody examination by enzyme-linked immunosorbent assay (ELISA). Western blot analysis was performed to distinguish the infected strains, and compared with two standard strains NCTC 11637 and CAPM N111, respectively. Similarity analysis was then carried out with Quantity one 4.1.1 software, which is special for photographs of electrophoresis.

RESULTS: The seroprevalence of H. pylori infection in residents of this area was of medium level in our country, and it was not associated with gender. In this area, the risk factors of infection were bad living conditions, overcrowding and possession of pigs during childhood, as well as several generations eating together, less vinegar and fruit intake. The overall prevalence and serum level of anti-H. pylori antibodies in 263 subjects was 57.41% and 0.911 ± 0.810 mg/L, respectively. In males, they were 60.50% and 0.948 ± 0.843 mg/L, while 54.86% and 0.880 ± 0.748 mg/L in females, respectively (P > 0.05). Infection clustered within families, and 60% and 51.35% of the children with two or at least one infected parent were H. pylori-positive, while the prevalence rate in the children with both parents uninfected was only 11.11% (P < 0.05). Western blot showed that the antibodies of the residents living in the area were similar in bands (F = 1.22, P > 0.05).

CONCLUSION: The prevalence of H. pylori in residents of this area was of medium level in our country. Infection clusters within families, and the status of parents' infection can affect that of the children.

Intra-familial transmission of Helicobacter pylori infection in children of households with multiple generations in Vietnam

This community-based cross-sectional study in 533 participants from 135 households with multiple generations living in the same household aimed at investigating the relationship between Helicobacter pylori infection in children and the other household members. H. pylori infection in children was found significantly associated with the infection in mothers [OR (95% CI): 2.50 (1.19-5.26)], even after being adjusted for sex, age group and sibling number [adjusted OR (95% CI): 2.47 (1.12-5.47)]. It was also significantly associated with the infection in both parents [adjusted OR (95% CI): 4.14 (1.29-13.23)]. No significant association between H. pylori infection in the father, grandparent(s), uncle or aunt with that in their children was found. Results from the present study showed intra-familial transmission in a multi-generation population and supported the hypothesis of person-to-person transmission of H. pylori infection.

Effects of Helicobacter pylori infection on gastric epithelial cell kinetics in patients with chronic renal failure

AIM

To evaluate the effects of Helicobacter pylori infection on gastric epithelial cell kinetics in patients with chronic renal failure (CRF).

METHODS

Forty-four patients were enrolled in this study and divided into four groups with respect to their Helicobacter pylori (H pylori) and CRF status. Groups were labeled as follows: 1a: normal renal function, H pylori negative (n = 12), 1b: normal renal function, H pylori positive (n = 11), 2a: CRF, H pylori negative (n = 10), 2b: CRF, H pylori positive (n = 11). Upper gastrointestinal endoscopy was done in all the patients involved in the study. During endoscopical investigation, antral biopsy specimens were taken from each patient. In order to evaluate the cell apoptosis and proliferation in gastric epithelial cells, Bax and proliferating cell nuclear antigen (PCNA) labeling indexes (LI) were assessed with immunohistochemical staining method.

RESULTS

For groups 1a, 1b, 2a, and 2b, mean Bax LI was identified as 34.4+/-13.7, 44.1+/-16.5, 46.3+/-20.5, 60.7+/-13.8, respectively and mean PCNA LI was identified as 36.2+/-17.2, 53.6+/-25.6, 59.5+/-25.6, 67.2+/-22, respectively. When the one-way ANOVA test was applied, statistically significant differences were detected between the groups for both Bax LI (P = 0.004 <0.01) and PCNA LI (P = 0.009 <0.01). When groups were compared further in terms of Bax LI and PCNA LI with Tukeyos HSD test for multiple pairwise comparisons, statistically significant difference was observed only between groups 1a and 2b (P = 0.006 <0.01).

CONCLUSION

In gastric epithelial cells, expression of both the pre-apoptotic protein Bax and the proliferation marker PCNA increase with H pylori infection. This increase is more evident in patients with uremia. These findings suggest that uremia accelerates apoptosis and proliferation in gastric epithelial cells.

Helicobacter pylori infection in 1st degree relatives of Chinese gastric cancer patients

OBJECTIVE

Familial aggregation of gastric cancer has been linked to familial clustering of Helicobacter pylori infection. Patterns and risk factors associated with H. pylori infection were investigated in 1st degree relatives of Chinese gastric cancer patients.

MATERIAL AND METHODS

Gastric cancer relatives were invited for screening endoscopy. H. pylori infection was diagnosed by endoscopic and serological methods.

RESULTS

Among the 270 cancer relatives examined, 161 (59.6%) were found to be infected with H. pylori. The prevalence of infection in cancer relatives was significantly higher than age- and gender-matched dyspeptic control (45.5%, p=0.0006). The mean age of H. pylori-infected relatives was significantly older than that of non-infected relatives (43.9 versus 38.3 years; p<0.001). The prevalence of H. pylori infection was higher in those with more siblings (p=0.013, chi(2) test for trend). Moreover, individuals whose siblings had stomach cancer were more likely to have H. pylori infection than those with a parental history of cancer (68.2% versus 51.8%, p=0.007). In contrast, the youngest sibling had a significantly lower H. pylori infection rate than other siblings (39.2% versus 64.2%, p=0.001). Using multiple logistic regression, it was found that age >45 years (OR=1.8; 95% CI, 1.02-3.3) and a history of gastric cancer in siblings (OR=1.9; 95% CI, 1.06-3.3) were independent risk factors for H. pylori infection, and that the youngest sibling in the family had a reduced risk (OR=0.45; 95% CI, 0.24-0.84).

CONCLUSIONS

This study identifies the patterns and risk factors for H. pylori in gastric cancer relatives, which may shed light on the evolving epidemiology of H. pylori infection in Chinese patients.

Risk factors associated with the development of intestinal metaplasia in first-degree relatives of gastric cancer patients

Family relatives of gastric cancer patients have a higher risk of gastric cancer and premalignant gastric lesions. We sought to determine the risk factors associated with the presence of intestinal metaplasia in a large cohort of gastric cancer relatives. First-degree relatives of gastric cancer patients were invited for screening gastroscopy. Endoscopic gastric biopsies were obtained from the antrum and corpus. Gastric biopsies were analyzed for Helicobacter pylori infection, severity of inflammation, and presence of intestinal metaplasia. Stepwise logistic regressions were used to identify for risk factors associated with presence of intestinal metaplasia in cancer relatives. Two hundred seventy cancer relatives underwent screening endoscopy (median age, 42; 47% male and 48% siblings). Among them, 161 (59.6%) were H. pylori positive and 81 (30%) had confirmed intestinal metaplasia. The following factors were found to be associated with the presence of intestinal metaplasia: age, male sex, H. pylori infection, birth order, alcohol use, siblings with stomach cancer, childhood living conditions, and water supply. Individuals with intestinal metaplasia had more severe acute and chronic inflammation in the antrum and corpus (P < 0.003). With multiple logistic regression, H. pylori infection [odds ratio (OR), 3.23], male gender (OR, 2.09), age (OR, 1.07), and a history of gastric cancer in siblings (OR, 1.91) were independent factors associated with the development of intestinal metaplasia in cancer relatives. In conclusion, we have identified risk factors associated with gastric intestinal metaplasia in stomach cancer relatives, which may be useful in the understanding of gastric carcinogenesis in these high-risk individuals.

Epidemiology of Helicobacter pylori infection in the Czech Republic

BACKGROUND

Prevalence of Helicobacter pylori infection has been estimated to range from 60 to 95% in the former communist countries of Central and Eastern Europe. The aim of this study was to evaluate H. pylori infection prevalence in a representative sample of the Czech population. The second objective was to describe difference of H. pylori prevalence between different social groups of children and adults.

MATERIALS AND METHODS

A total of 2509 persons aged 5-100 years, randomly selected out of 30,012 persons of the general population, took part in the study. H. pylori infection was investigated by means of 13C-urea breath test. Breath samples were analyzed by isotope ratio mass spectrometry. Social and demographic characteristics were based on data from self-completed questionnaires.

RESULTS

Using the total Czech population as a standard, we estimated the age-standardized prevalence of H. pylori in males aged 5+ years at 41.9% (95% CI 39.0%, 44.8%) and in females aged 5+ years at 41.4% (95% CI 38.6%, 44.3%) in 2001. Prevalence of H. pylori increased with age but was not related to gender. Children of mothers with basic or lower education, living in crowded accommodations, without access to running warm water, and residing in smaller towns appear to be at the highest risk. Low education and heavy smoking are most strongly associated with prevalence of H. pylori positivity in adults and adolescents.

CONCLUSIONS

This is a unique study based on a representative sample of the general population in a Central European country. The overall prevalence of H. pylori is lower than previously assumed and could partly reflect a substantial recent decrease in H. pylori prevalence in the Czech Republic. Consistent with earlier studies, H. pylori infection is strongly influenced by socioeconomic conditions and childhood poverty.

Prevalence and risk factors of Helicobacter pylori infection in healthy schoolchildren

OBJECTIVE

Data regarding the prevalence of Helicobacter pylori infection and its potential risk factors among schoolchildren from the Middle East is scarce.

METHODS

An enzyme-linked immunosorbent assay was used to investigate H. pylori status in four groups of children: The first and second groups, 50 children each (25 boys, 25 girls) included children from high socioeconomic class (group 1 = 6 years old; group 2 = 9 years old). The third and fourth groups were sex- and age-matched, but from low socioeconomic class. To evaluate the association between the seroprevalence of H. pylori and selected risk factors, odds ratios (crude and adjusted) were calculated using multiple regression analysis.

RESULTS

Overall seroprevalence rate was 55.5%. Seropositivity was 42%, 52%, 60%, and 68% for groups 1, 2, 3, and 4, respectively. Age and sex were not significantly associated with H. pylori seropositivity. In the final logistic regression model, which was adjusted for age and sex, the following risk factors were found to be significantly associated with seropositivity: living in rural areas (P = 0.015), poor sanitation (P < 0.001), overcrowding (P = 0.014), low maternal educational level (P = 0.010) and low socioeconomic status (P = 0.011).

CONCLUSIONS

The prevalence of H. pylori infection in Jordanian schoolchildren is high, suggesting that most acquisition occurs before the age of 6 years. The seroprevalence for H. pylori increases with social deprivation.

Application of a stool antigen test to evaluate the incidence of Helicobacter pylori infection in children and adolescents from Tehran, Iran

Helicobacter pylori infection is acquired mainly in childhood, especially in developing countries, where a low-cost, rapid diagnostic technique which is reliable for all age groups may be useful for the management of H. pylori infection. For this purpose, we used an HpSA test (Equipar) to detect H. pylori infection in children and adolescents from Tehran, Iran. Thirty-five children who were positive or negative for H. pylori infection by endoscopy-based tests were used as positive and negative controls for the HpSA test. Stools were collected from 430 randomly selected children and adolescents (4 to 18 years old) from southwest, near the center, and northwest of Tehran. A questionnaire that included presence of recurrent abdominal pain (RAP), family history of infection and/or peptic ulcer disease (PUD), and income of parents was completed. A good agreement was found between the results of endoscopy-based tests and those of the HpSA test; the sensitivity and specificity of the Equipar-HpSA test were 100% and 83.4%, respectively. Among 430 children and adolescents, 47% were positive by the HpSA test, of whom 82% had RAP. No difference in incidence was observed between the two sexes; the various categories of age showed an increasing incidence, ranging from 24% (ages 4 to 6) to 58% (ages 16 to 18). The rate of infection in children and adolescents from the southwest was significantly higher (70%) than the rate in those from the northwest (32%), and a family history of H. pylori infection or PUD was observed in 59% of the HpSA positive subjects. The HpSA test is a useful test to detect H. pylori infection in children and adolescents from developing countries.

Associations between three types of maternal bacterial infection and risk of leukemia in the offspring

A case-control study was nested within two maternity cohorts with a total of 7 million years of follow-up for assessment of the role of bacterial infections in childhood leukemia. Offspring of 550,000 mothers in Finland and Iceland were combined to form a joint cohort that was followed for cancer up to age 15 years during 1975-1997 through national cancer registries. For each index mother-case pair, three or four matched control mother-control pairs were identified from population registers. First-trimester serum samples were retrieved from mothers of 341 acute lymphoblastic leukemia cases and 61 other leukemia cases and from 1,212 control mothers. Sera were tested for antibodies to the genus Chlamydia, Helicobacter pylori, and Mycoplasma pneumoniae. Odds ratios and 95% confidence intervals, adjusted for sibship size, were calculated as estimates of relative risk. M. pneumoniae immunoglobulin M appeared to be associated with increased risk (odds ratio (OR) = 1.6), but the association lost statistical significance when the specificity of the immunoglobulin M was considered (OR = 1.5, 95% confidence interval: 0.9, 2.4). In Iceland, H. pylori immunoglobulin G was associated with increased risk of childhood leukemia in offspring (OR = 2.8, 95% confidence interval: 1.1, 6.9). Since H. pylori immunoglobulin G indicates chronic carriage of the microorganism, early colonization of the offspring probably differs between Iceland and Finland, two affluent countries.

Helicobacter pylori antibodies and gastric cancer: a gender-related difference

Helicobacter pylori has been proposed as a causative agent of gastric cancer. The aim of this study was to define serum antibodies response against different H. pylori antigens in patients with gastric cancer. Serum samples were collected from 115 Lithuanian patients with non-cardia gastric cancer and 110 age- and sex-matched controls without cancer. Heat-stable, low-molecular-mass, and outer membrane proteins were used as antigens to analyze serum IgG antibody response against H. pylori by enzyme-linked immunosorbent assay. Seroprevalence of H. pylori using low-molecular-mass antigen was significantly higher in gastric cancer patients, compared to controls (77% versus 57%, p<0.05). Significant differences in the prevalence of H. pylori infection between gastric cancer patients and controls were found in females using all three studied antigens: heat-stable (98% versus 84%, p<0.05), low-molecular-mass (88% versus 48%, p<0.05) and outer membrane proteins (78% versus 57%, p<0.05). In males, no significant differences were revealed between gastric cancer patients and controls. There may be other cofactors in addition to H. pylori that are important for the development of gastric cancer. H. pylori seems, however, to be a more important for development of gastric cancer in females than in males or males may have more confounding risk factors for gastric cancer than females.

Helicobacter pylori eradication has the potential to prevent gastric cancer: a state-of-the-art critique

Helicobacter pylori infection continues to play a key role in gastric diseases. Colonization of the gastric mucosa with the bacterium invariably results in the development of chronic gastritis and subsets of patients have a progression of the chronic gastritis to either ulcer or cancer. Epidemiological evidence indicates that the proportion of all gastric cancers attributable to H. pylori infection, and hence potentially preventable upon elimination of this risk factor, is somewhere in the range of 60% to 90%. This portends significant benefit in terms of morbidity and mortality, not least in populations with high prevalence of H. pylori infection coupled with high incidence of gastric cancer. The effect of prophylactic H. pylori eradication on gastric cancer incidence in humans remains unknown, however. Results from randomized trials are eagerly awaited, but availability of strong conclusive results may take many years. A growing number of studies show considerable variation in risk for gastric cancer development, depending on H. pylori strain type and the genetic predisposition of the host. There is also a remote possibility that elimination of the infection may have adverse health implications (e.g., antibiotic resistance), and therefore "simple" risk stratification and targeted chemoprevention is required. Based on "in depth" evidence presented at this workshop, the majority of the scientific task force favored a search-and-treat strategy in first-degree relatives of gastric cancer patients and an overwhelming majority felt that a more general screen-and-treat strategy should be focused in the first instance on a population with a high incidence of H. pylori-associated diseases.

14C-urea breath test in patients undergoing anti-tuberculosis therapy

AIM: Urea breath test (UBT) is a non-invasive diagnostic test for detecting the presence of Helicobacter pylori (H pylori). In this study we evaluated the effect of anti-tuberculosis therapy on the results of ¹⁴C-UBT.

METHODS: Patients, with the diagnosis of tuberculosis (TB) who had a positive UBT at the point of starting anti-TB therapy, were included. None had a history of peptic ulcer disease or had taken antibiotics, bismuth compounds and/or PPI in the previous month. ¹⁴C-UBT was repeated at the end of the second month and the end of treatment period and one month after completion of treatment course.

RESULTS: Thirty-five patients (23 males) were enrolled. ¹⁴C-UBT was negative in all 35 patients (100%) at the end of the second month and remained negative in 30 cases (85.7%) at the end of the treatment course. One month after completion of treatment course, UBT remained negative in 13 patients (37.1%).

CONCLUSION: Our report underscores the need for caution while interpreting urea breath test results in patients undergoing anti-TB therapy. Furthermore, the combination of drugs used in this study resulted in H pylori eradication in a minority of patients.

A negative Helicobacter pylori serology test is more reliable for exclusion of premalignant gastric conditions than a negative test for current H. pylori infection: a report on histology and H. pylori detection in the general adult population

OBJECTIVE

Corpus-dominant gastritis, gastric mucosal atrophy and intestinal metaplasia (IM) associated with Helicobacter pylori infection are all known potential risk markers for the development of gastric cancer. As the accuracy for finding cases at risk in the general population is unknown, we aimed to determine the prevalence of current and/or past H. pylori infection and associated gastric mucosal findings by means of histological survey of a random adult population.

MATERIAL AND METHODS

A random Swedish sample (n = 3000, age 20-81 years) was surveyed using a validated gastrointestinal symptom questionnaire with 74% response rate. One-third of the responders were selected at random for esophago-gastro-duodenoscopy with biopsies and H. pylori serology.

RESULTS

Of those endoscoped (n = 1000, mean age 53.5, 51% women), 43.0% were H. pylori+ by serology (seropositive), 33.9% had signs of current infection on either histology or culture (gold standard+), and 9.3% were seropositive, but gold standard negative. Corpus atrophy was found in 10% and IM in 13% when gold standard positive, and in a significantly higher number (17% and 21%, respectively) of those with only a serological sign of past infection. Among those who were seronegative, values were 1% and 2%, respectively. Corpus-dominant gastritis was found in 4.1%, all seropositive.

CONCLUSION

One-third had an ongoing H. pylori infection, and a further 10% had signs of past infection. Corpus-dominant gastritis was found mostly among the former, while detection of those with corpus atrophy and IM also required a test for past infection. Seronegativity almost excludes precancerous conditions in a screening situation.

Heme iron, zinc and upper digestive tract cancer: The Iowa Women's Health Study

We examined associations among dietary heme iron as a possible pro-oxidant, dietary zinc as a possible antioxidant, and the incidence of upper digestive tract cancer; 34,708 postmenopausal women, aged 55-69 years at baseline who completed a food frequency questionnaire, were followed 16 years. There were 75 upper digestive tract cancer cases (52 gastric cancer and 23 esophageal cancer). When heme iron and zinc were mutually adjusted, in dose-response manners, heme iron intake was positively associated with the risk of upper digestive tract cancer, while zinc intake was inversely associated with risk. After adjusting for age, total energy intake, cigarette smoking and alcohol consumption, relative risks for quintiles of heme iron intake were 1.0, 1.53, 2.15, 3.05 and 2.83 (p for trend = 0.06) and corresponding relative risks for zinc intake were 1.0, 0.86, 0.42, 0.37 and 0.13 (p for trend < 0.01). Additional adjustment for body mass index, physical activity, hormone replacement therapy, multivitamin intake and intake of saturated fat, vitamin C, vitamin E and folate did not change the results. Higher intake of heme iron is associated with higher risk, while higher intake of zinc is associated with lower, risk of upper digestive tract cancer.

Epidemiology of Helicobacter pylori infection

This review summarizes key results of epidemiologic studies published in peer-reviewed journals between April 2003 and March 2004. The prevalence of H. pylori infection continues to vary strongly between developing countries and developed countries, and according to ethnicity, place of birth and socioeconomic factors among people living in the same country. Intrafamilial spread appears to play a central role in transmission of the infection in both developing and developed countries. The role of H. pylori infection in development of noncardia gastric cancer appears to be even much stronger than previously assumed, whereas the lack of an association with cardia cancer and an inverse association with adenocarcinoma of the esophagus could be confirmed. Suggestions for an inverse association of the infection with atopic diseases have recently received further support, whereas evidence concerning the role of the infection (or its eradication) in GERD and a large variety of other extragastric diseases, including cardiovascular disease, remains inconclusive.