Seroprevalence of immunoglobulin G, M, and A antibodies to Helicobacter pylori in an unselected Danish population

Changes in Seroprevalence of Helicobacter pylori Infection over 20 Years in Jinju, Korea, from Newborns to the Elderly

BACKGROUND

The objective of this study was to examine changes in the prevalence of cytotoxic-associated gene A (CagA) positive Helicobacter pylori infection in Jinju, Korea, over the last 20 years.

METHODS

Three cross-sectional analyses were conducted concurrently. A total of 1,305 serum samples were collected from 1994-1995, 2004-2005, and 2014-2015, respectively. The presence of immunoglobulin (Ig) G, IgA, and IgM antibodies against H. pylori CagA protein was examined by western blotting.

RESULTS

Overall, seropositivity for anti-CagA IgG antibody was significantly decreased from 63.2% to 42.5% over the last 20 years (P < 0.001). Anti-CagA IgG seropositivities in children and young adults aged 10-29 years decreased from 1994 (60.0%-85.0%) to 2015 (12.5%-28.9%). The age when plateau of increasing IgG seropositivity was reached in each study period shifted from the 15-19 year-old group in 1994-1995 (85.0%) to the 40-49 year-old group in 2014-2015 (82.5%). Overall seropositive rates of anti-CagA IgA and IgM antibodies did not change significantly either over the last 20 years.

CONCLUSION

H. pylori infection rate in children and young adults declined over 20 years in Jinju, probably due to improved sanitation, housing, or economy.

Profile of peptic ulcer disease and its risk factors in Arar, Northern Saudi Arabia

Background

Peptic ulcer disease is a multifactorial health problem, and its prevalence and risk factors have changed considerably within the past century.

Objective

To determine the prevalence of peptic ulcer among the population of Arar city and to identify risk factors for peptic ulcer and to estimate their relative impact on ulcer incidence.

Methods

A cross-sectional study was carried out on the population of Arar city, Northern Saudi Arabia from November 01, 2016 to April 30, 2017. Data were analyzed by SPSS version 16, using descriptive statistics, prevalence, and Chi-square test.

Results

Total prevalence of peptic ulcer among the studied respondents was thus: 21.9% had peptic ulcer; 16.2% gastric ulcer and 5.6% duodenal ulcer. In 19.7% of the cases, the pain was severe, 92.4% reported that pain was precipitated by certain food. In addition to heartburn, 78.8% reported loss of appetite, 71.2% indigestion, 66.7% regurgitation, 59.1% nausea and vomiting and 42.4% with chest pain. Regarding the risk factors, coffee drinking came in first place (81.8%) followed by physical stress in 77.3%, spicy food in 57.6%, prolonged use of Non-steroidal anti-inflammatory drugs (NSAIDs) in 33.3% and Helicobacter pylori (H. pylori) infection in 24.2%. A further 22.7% reported melena as a complication while only 10.6% reported hematemesis.

Conclusion

This is the first population-based study in Arar, Northern Saudi Arabia reporting point prevalence of peptic ulcer disease. The rate of 16.2% for gastric ulcer and 5.6% for duodenal ulcers are substantially high. Coffee drinking, physical stress, spicy food, prolonged use of NSAID and H. pylori infection were the reported risk factors. Population-based endoscopic studies are recommended.

Analysis of Helicobacter pylori Prevalence in Chittagong, Bangladesh, Based on PCR and CLO Test

The pathogenic bacterium Helicobacter pylori is a causative agent of gastric diseases in Bangladesh as well as throughout the world. This study aimed at analyzing the prevalence of H. pylori infection among dyspeptic patients in Chittagong, the second most populous city of Bangladesh, using 16S rRNA-based H. pylori-specific Polymerase Chain Reaction and Campylobacter-like organism test. We found that 67% of the population under study was positive for H. pylori infection. Gastric ulcer and duodenal ulcer disease showed statistically significant association with H. pylori infection; however, no association of H. pylori infection was observed in terms of age and gender. This study would play a crucial role in managing H. pylori-induced gastric diseases by understanding the current trend of H. pylori infection in the Chittagong region of Bangladesh.

Association of endothelial dysfunction and cytotoxin-associated gene A-positive Helicobacter pylori in patients with cardiac syndrome X

Background

Existence of coronary endothelial dysfunction has been demonstrated in patients with cardiac syndrome X (CSX). In addition, Helicobacter pylorus (H. pylori) has been associated with CSX. We aimed to assess the possible association of endothelial dysfunction and cytotoxin-associated gene A-positive H. pylori (CagA+) infection in CSX patients.

Methods

Fifty-six patients with CSX (23 male/33 female; age: 51.25 ± 8.86 years) who were anti-H. pylori IgG-positive [H. pylori(+)] and 24 CSX patients (7 male/17 female; age: 52.79 ± 9.88 years) who were H. pylori(−) were included. Also, anti-H. pylori IgG-positive patients were determined by the presence of IgG antibody to CagA. Levels of endothelin-1 (ET-1), E-selectin and intercellular adhesion molecule-1 (ICAM-1) were measured.

Results

Endothelial dysfunction biomarkers were higher in H. pylori(+) than in H. pylori(−) patients (ET-1: 54.60 ± 25.39 vs. 42.59 ± 18.37 pg/ml, p = 0.04; E-selectin: 42.68 ± 14.26 vs. 31.72 ± 8.26 ng/ml, p = 0.001; ICAM-1: 339.68 ± 135.8 vs. 266.51 ± 125.1 ng/ml, p = 0.02). Among H. pylori(+) subjects, 28 cases were CagA(+) and 28 cases were CagA(−). There were significant differences in measured levels of E-selectin between CagA(+) and CagA(−) groups (48.00 ± 16.37 vs. 37.37 ± 9.37 ng/ml, p = 0.004). For ET-1 and ICAM-1 levels, the difference between CagA(+) and CagA(−) was insignificant (p = 0.174 and p = 0.07, respectively).

Conclusion

High levels of endothelial dysfunction biomarkers are found in CSX patients with anti-CagA(+). These findings suggest the infection with CagA(+) H. pylori strain may play a role as a risk factor in development of CSX through provocation of endothelial dysfunction. Therefore, a long term follow up to investigate the outcomes of these patients is proposed.

Review article: the global emergence of Helicobacter pylori antibiotic resistance

BACKGROUND

Helicobacter pylori is one of the most prevalent global pathogens and can lead to gastrointestinal disease including peptic ulcers, gastric marginal zone lymphoma and gastric carcinoma.

AIM

To review recent trends in H. pylori antibiotic resistance rates, and to discuss diagnostics and treatment paradigms.

METHODS

A PubMed literature search using the following keywords: Helicobacter pylori, antibiotic resistance, clarithromycin, levofloxacin, metronidazole, prevalence, susceptibility testing.

RESULTS

The prevalence of bacterial antibiotic resistance is regionally variable and appears to be markedly increasing with time in many countries. Concordantly, the antimicrobial eradication rate of H. pylori has been declining globally. In particular, clarithromycin resistance has been rapidly increasing in many countries over the past decade, with rates as high as approximately 30% in Japan and Italy, 50% in China and 40% in Turkey; whereas resistance rates are much lower in Sweden and Taiwan, at approximately 15%; there are limited data in the USA. Other antibiotics show similar trends, although less pronounced.

CONCLUSIONS

Since the choice of empiric therapies should be predicated on accurate information regarding antibiotic resistance rates, there is a critical need for determination of current rates at a local scale, and perhaps in individual patients. Such information would not only guide selection of appropriate empiric antibiotic therapy but also inform the development of better methods to identify H. pylori antibiotic resistance at diagnosis. Patient-specific tailoring of effective antibiotic treatment strategies may lead to reduced treatment failures and less antibiotic resistance.

Helicobacter pylori antibody patterns in Germany: a cross-sectional population study

BACKGROUND

Helicobacter pylori infection that is usually acquired in childhood and lasts for lifetime is mostly asymptomatic but associated with severe gastrointestinal disease including cancer. During chronic infection, the gastric mucosa is histologically changing. This forces H. pylori to permanent adaptation in its gastric habitat by expression of different proteins which might be reflected in distinctive antibody patterns.

METHODS

To characterize dynamics of the immune response to H. pylori we analysed 1797 sera of a cross-sectional study representative for the German population (age range 1-82 years) with multiplex serology, a fluorescent bead-based antibody binding assay that allows simultaneous and quantitative detection of antibodies. Fifteen recombinant, affinity-purified H. pylori proteins (UreA, GroEL, Catalase, NapA, CagA, CagM, Cagδ, HP0231, VacA, HpaA, Cad, HyuA, Omp, HcpC and HP0305) were used as antigens.

RESULTS

H. pylori seroprevalence (positivity for at least three antigens) was 48% and increased with age from 12% in children <15 years to 69% in females and 90% in males >65 years. Prevalences were highest (>83%) for Omp, VacA and GroEL. For 11 proteins, seroprevalence was higher in males than females (P < 0.05) from age 55 onwards. For all antigens, the median prevalence increase per age decade was stronger in males (8.4%, range 3.8-12.9%) than females (6.1%, range 3.4-10.8%). However, among seropositives the median number of antigens recognized increased from children <15 years to individuals >65 years stronger in females (P = 0.02). Antibody reactivities to GroEL, HyuA, CagM, Catalase, NapA and UreA also increased stronger in females (average 1.7-fold/decade, SD 0.5) than in males (1.5-fold/decade, SD 0.4).

CONCLUSION

H. pylori antibody response accumulates qualitatively and quantitatively with age. This may reflect a lifelong stimulation of the immune response by chronically active infection.

The prevalence of Helicobacter pylori infection in the Netherlands

BACKGROUNDS

The prevalence of Helicobacter pylori has been declining in the developed countries, as it has the incidence of distal gastric carcinoma. Monitoring this decline and identifying populations not benefiting from this decline is a fit task for public health authorities, with blood donors an obvious source of sera.

MATERIALS AND METHODS

We tested 1550 randomly selected blood donors, spread over 5-10 year age cohorts, from four regions in the southern half of The Netherlands, for the presence of antibodies against H. pylori and the CagA antigen. These donors were drawn from an area comprising 46% of the native Dutch population, but did not include non-European immigrants.

RESULTS

We observed an age specific decline in the mean seroprevalence of H. pylori from 48% for donors born between 1946 and 1935 to 16% for those born between 1987 and 1977. In H. pylori positive donors, the CagA seroprevalence declined from 38% to 14% in the same age cohorts. There were no significant differences between regions in either prevalence.

CONCLUSIONS

Our results are compatible with a persistent age-cohort phenomenon for H. pylori prevalence, with the most pronounced decline of CagA+ strains. Nevertheless, almost one in six of the young native Dutch population remains H. pylori positive, implying that, without specific intervention, this bacterium will remain common over the coming decades.

Longitudinal analysis of serological responses of adults to Helicobacter pylori antigens

Because Helicobacter pylori persist for decades in the human stomach, the aim of this study was to examine the long-term course of H. pylori-specific serum immunoglobulin G (IgG) responses with respect to subclass and antigenic target. We studied paired serum samples obtained in 1973 and in 1994 in Vammala, Finland, from 64 healthy H. pylori-positive adults and from other healthy control subjects. H. pylori serum immunoglobulin A, IgG, and IgG subclass responses were determined by antigen-specific enzyme-linked immunosorbent assays. H. pylori-specific IgG1 and IgG4 subtype responses from 47 subjects were similar in 1973 and 1994, but not when compared with unrelated persons. H. pylori-specific IgG1:IgG4 ratios among the participants varied >1000-fold; however, 57 (89.1%) of 64 subjects had an IgG1:IgG4 ratio >1.0, consistent with a predominant IgG1 (Th1) response. Furthermore, ratios in individual hosts were stable over the 21-year period (r = 0.56; P < .001). The immune response to heat shock protein HspA was unchanged in 49 (77%) of the 64 subjects tested; of the 15 whose serostatus changed, all seroconverted and were significantly younger than those whose status did not change. These findings indicate that H. pylori-specific antibody responses are host-specific with IgG1:IgG4 ratios stable over 21 years, IgG1 responses predominating, and HspA seroconversion with aging.

Helicobacter pylori: a poor man's gut pathogen?

Helicobacter pylori is one of the human pathogens with highest prevalence around the world; yet, its principal mode of transmission remains largely unknown. The role of H. pylori in gastric disease and cancer has not been established until the end of the 20^th century. Since then, its epidemiology has been extensively studied, and an accruing body of literature suggests that not all humans are equally at risk of infection by this gut pathogen. Here, we briefly review the different epidemiological aspects of H. pylori infection with emphasis on those factors related to human poverty. The epidemiology of H. pylori infection is characterized by marked differences between developing and developed countries, notably among children. In addition, congruent lines of evidence point out to socioeconomic factors and living standards as main determinants of the age-dependent acquisition rate of H. pylori, and consequently its prevalence. These data are alarming in the light of the changing global climate and birth rate, which are expected to change the demography of our planet, putting more children at risk of H. pylori and its complications for years to come.

Helicobacter pylori: a poor man's gut pathogen?

Helicobacter pylori is one of the human pathogens with highest prevalence around the world; yet, its principal mode of transmission remains largely unknown. The role of H. pylori in gastric disease and cancer has not been established until the end of the 20th century. Since then, its epidemiology has been extensively studied, and an accruing body of literature suggests that not all humans are equally at risk of infection by this gut pathogen. Here, we briefly review the different epidemiological aspects of H. pylori infection with emphasis on those factors related to human poverty. The epidemiology of H. pylori infection is characterized by marked differences between developing and developed countries, notably among children. In addition, congruent lines of evidence point out to socioeconomic factors and living standards as main determinants of the age-dependent acquisition rate of H. pylori, and consequently its prevalence. These data are alarming in the light of the changing global climate and birth rate, which are expected to change the demography of our planet, putting more children at risk of H. pylori and its complications for years to come.

IgA antibodies in persisting Helicobacter pylori infection in Finnish adults

Most individuals infected with Helicobacter pylori have elevated levels of specific IgG antibodies, but only in about two-thirds of cases does the IgA titre exceed the cut-off level. The aim of this study was to determine whether H. pylori-infected subjects with elevated IgG levels would subsequently produce IgA antibodies, and whether elevated IgA levels increased during infection. Paired sera were available from 336 adults who took part in a large population-based health survey in 1977-1980 and a follow-up study on asthma and atopic diseases in 1997-1998 (series A). Data on paired sera from 224 adults who participated in a population-based health survey in Vammala, Finland in 1973 and who gave a follow-up blood sample in 1994 (series B) were also re-analysed. H. pylori IgG and IgA levels were determined with commercially available (series A) and in-house (series B) enzyme immunoassays. Twenty-one (35%) of the 60 subjects who initially had elevated levels of IgG antibodies only were found to be IgA-positive at follow-up. In those subjects whose baseline and follow-up samples were IgG- and IgA-positive, the median IgA levels increased by 48% and 22% in series A and B (p < 0.0001 and p 0.0241), respectively, whereas the median IgG levels did not change significantly in either series. During H. pylori infection, an increase in specific IgA was reflected by the increase in the number of responders and by the rise in titres.

Association of Helicobacter pylori IgA antibodies with the risk of peptic ulcer disease and gastric cancer

AIM

To compare the prevalence of Helicobacter pylori (H pylori) IgG and IgA antibodies between adult subjects, with defined gastric diseases, non-defined gastric disorders and those representing the population.

METHODS

Data on H pylori IgG and IgA antibodies, determined by enzyme immunoassay, were analyzed in 3,252 subjects with DGD including 482 patients with gastric ulcer, 882 patients with duodenal ulcer, 1,525 patients with chronic gastritis only and 363 subjects with subsequent gastric cancer, 19,145 patients with NoDg and 4,854 POPUL subjects. The age-adjusted prevalences were calculated for 1- and 20-year age cohorts.

RESULTS

The prevalences of IgG antibodies were equally high (89-96%) in all 20-year age cohorts of the DGD groups, whereas the prevalences of IgG antibodies were lower and increased by age in the POPUL and NoDg groups. The prevalences of IgA antibodies were also higher in the DGD groups; among them CA (84-89%) and GU groups (78-91%) showed significantly higher prevalences than DU (68-77%) and CG patients (59-74%) (OR 2.49, 95%CI 1.86-3.34 between the GU and DU groups). In the CA, GU, and DU groups, the IgA prevalences showed only minor variation according to age, while they increased by age in the CG, POPUL, and NoDg groups (P<=0.0001). The IgA response, but not the IgG response, was associated with an increased risk of CA (OR 2.41, 95%CI 1.79-3.53) and GU (OR 2.57, 95%CI 1.95-3.39) in comparison with CG patients.

CONCLUSION

An IgA antibody response during H pylori infection is significantly more common in CA and GU patients as compared with CG patients.

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.

B-cell and T-cell immune responses to experimental Helicobacter pylori infection in humans

The acute antibody and T-cell immune response to Helicobacter pylori infection in humans has not been studied systematically. Serum from H. pylori-naive volunteers challenged with H. pylori and cured after 4 or 12 weeks was tested by enzyme-linked immunosorbent assays for anti-H. pylori-specific immunoglobulin M (IgM) and IgA established using bacterial lysates from homologous (the infecting strain) and heterologous H. pylori. Proteins recognized by IgM antibody were identified by mass spectrometry of immunoreactive bands separated by two-dimensional gel electrophoresis. Mucosal T-cell subsets (CD4, CD8, CD3, and CD30 cells) were assessed by immunohistochemistry. All 18 infected volunteers developed H. pylori-specific IgM responses to both homologous or heterologous H. pylori antigens. H. pylori antigens reacted with IgM antibody at 4 weeks postinfection. IgM Western blotting showed immunoreactivity of postinfection serum samples to multiple H. pylori proteins with molecular weights ranging between 9,000 (9K) to 150K with homologous strains but only a 70K band using heterologous antigens. Two-dimensional electrophoresis demonstrated that production of H. pylori-specific IgM antibodies was elicited by H. pylori flagellins A and B, urease B, ABC transporter binding protein, heat shock protein 70 (DnaK), and alkyl hydroperoxide reductase. Mucosal CD3, CD4, and CD8 T-cell numbers increased following infection. IgM antibody responses were detected to a range of homologous H. pylori antigens 2 to 4 weeks postchallenge. The majority of H. pylori proteins were those involved in motility and colonization and may represent targets for vaccine development.

Detection of anti-Helicobacter pylori antibodies in serum and duodenal fluid in peptic gastroduodenal disease

AIM: To study the diagnosis of Helicobacter pylori (H pylori) infection through the determination of serum levels of anti-H pylori IgG and IgA antibodies, and the levels of anti-H pylori IgA antibodies in duodenal fluid.

METHODS: Data were collected from 93 patients submitted to upper digestive endoscopy due to dyspeptic symptoms. The patients were either negative (group A) or positive (group B) to H pylori by means of both histological detection and urease tests. Before endoscopy, peripheral blood was collected for the investigation of anti-H pylori IgG and IgA antibodies. To perform the urease test, biopsies were obtained from the gastric antrum. For the histological evaluation, biopsies were collected from the gastric antrum (greater and lesser curvatures) and the gastric body. Following this, duodenal fluid was collected from the first and second portions of the duodenum. For the serological assaying of anti–H pylori IgG and IgA, and anti-H pylori IgA in duodenal fluids, the ELISA method was utilized.

RESULTS: The concentration of serum IgG showed sensitivity of 64.0%, specificity of 83.7%, positive predictive value of 82.0%, negative predictive value of 66.6% and accuracy of 73.1% for the diagnosis of H pylori infection. For the same purpose, serum IgA showed sensitivity of 72.0%, specificity of 65.9%, positive predictive value of 72.0%, negative predictive value of 67.4% and accuracy of 69.8%. If the serological tests were considered together, i.e. when both were positive or negative, the accuracy was 80.0%, sensitivity was 86.6%, specificity was 74.2%, positive predictive value was 74.2% and negative predictive value was 86.6%. When values obtained in the test for detecting IgA in the duodenal fluid were analyzed, no significant difference (P = 0.43) was observed between the values obtained from patients with or without H pylori infection.

CONCLUSION: The results of serum IgG and IgA tests for H pylori detection when used simultaneously, are more efficient in accuracy, sensitivity and negative predictive value, than those when used alone. The concentration of IgA antibodies in duodenal fluid is not useful in identifying patients with or without H pylori.

Empiric treatment with high and standard dose of omeprazole in general practice: two-week randomized placebo-controlled trial and 12-month follow-up of health-care consumption

OBJECTIVES

Patients with acid-related symptoms in general practice are often treated empirically with a standard dose of proton pump inhibitors (PPIs). The effect of higher doses is not known. The study compared the immediate symptom relieving as well as the long-term effect of standard and double dose of omeprazole in such patients.

METHODS

Consecutive patients with dyspeptic symptoms, normally treated by the general practitioner with PPIs or H2-blockers were randomized to treatment with omeprazole 40 mg, 20 mg, or placebo in the morning for 2 wk. Patients with alarm symptoms, IBS, and PPI-treated patients were excluded. Dyspeptic symptoms and Helicobacter pylori status were recorded. The study endpoint was complete relief of the dyspeptic symptoms, which initiated the consultation. Relapse rates and health-care consumption were recorded during 12-month observation.

RESULTS

Eight hundred and twenty-nine patients were randomized. Complete relief of the predominant symptom was obtained by 66%, 63%, and 35% in patients treated with omeprazole 40 mg, 20 mg, and placebo, respectively. No difference was found comparing H. pylori-positive and -negative patients. Relapse rates were high and health-care consumption during 12 months was related to the treatment outcome, but not to the omeprazole dose or the H. pylori status.

CONCLUSIONS

Compared to placebo, omeprazole 40 mg and 20 mg were equally and significantly better in relieving acid-related symptoms; the numbers needed-to-treat (NNT) were 3.2 (40 mg) and 3.7 (20 mg). Relief of the dyspeptic complaint was followed by significantly reduced health-care consumption during 12-month observation.

Burden of Helicobacter pylori and H. pylori-related diseases in developed countries: recent developments and future implications

Helicobacter pylori colonizes the gastric mucosa. H. pylori infection is the main cause of peptic ulcer and gastric malignancy. This review gives an overview on the epidemiology of H. pylori infection and H. pylori-associated diseases in the developed world, mainly Europe, and it discusses very recent developments with regard to the prevalence and its future implications for H. pylori-associated diseases.

Changing rates of Helicobacter pylori testing and treatment in patients with peptic ulcer disease

OBJECTIVES

The aim of this study was to identify temporal trends in the rate of Helicobacter pylori (H. pylori) testing, prevalence, and treatment among patients with peptic ulcer disease in Olmsted County, MN, from 1984 through 1997.

METHODS

All 3317 Olmsted County residents with a clinical diagnosis of peptic ulcer disease at the Mayo Clinic from 1984 through 1997 were identified. The complete medical records of an age-, sex-, and calendar year-stratified random sample were reviewed (n = 720); 298 patients (41%) had confirmed peptic ulcer disease. Changes in proportions of H. pylori testing, infection, and treatment over time were analyzed by logistic regression.

RESULTS

Of the 298 patients with confirmed peptic ulcer disease, 32% were tested for H. pylori; 36% were positive for infection, of whom 66% received antibiotic therapy. The rate of testing for H. pylori increased from 0% in 1984 to 96% in 1997, but the prevalence of infection did not change (36.4% vs 36.5%). The rate of treatment of those infected increased from 0% to 95%. By logistic regression, calendar year was associated with H. pylori testing and treatment but not infection. Recent use of nonsteroidal anti-inflammatory drugs was reported by 58% of patients, and 44% presented with GI bleeding.

CONCLUSIONS

Physicians' practice of testing and treating for H. pylori in patients with confirmed peptic ulcer disease has steadily increased over the past 14 yr. However, in our study, only 36% of these patients were infected with H. pylori, whereas the majority used nonsteroidal anti-inflammatory drugs (NSAIDs). Therefore, testing seems to be more appropriate than empiric treatment in patients with peptic ulcer disease.

Nizatidine and omeprazole enhance the effect of metronidazole on Helicobacter pylori in vitro

Treatment failures are common in patients infected with metronidazole-resistant Helicobacter pylori in the gastric mucosa when triple therapy including metronidazole is used. In patients with treatment failure and metronidazole-resistant H. pylori, a higher eradication rate for H. pylori was found after secondary treatment with bismuth/ranitidine in combination with antibiotics including metronidazole, compared with the same antibiotics combined with a standard dose of omeprazole. This agrees with our previous finding that bismuth was able to reduce the susceptibility of H. pylori to metronidazole. In this study, we have found that nizatidine, an H(2)-receptor antagonist, is also able to reduce the susceptibility of H. pylori to metronidazole in vitro, despite having no direct inhibitory effect on the growth of H. pylori. This agrees with earlier findings that compounds having the ability to reverse antibiotic resistance do not necessarily have an antibiotic or chemotherapeutic effect in the sense of growth inhibition. Therefore, it was decided to investigate the effect of nizatidine and omeprazole on the oxidative respiratory chain, as it is known that metronidazole is able to inhibit the activity of fumarate reductase of H. pylori. This enzyme is a key enzyme in the alternative respiratory chain under anaerobic conditions. Nizatidine was, in these preliminary experiments, found to inhibit fumarate reductase in a dose-dependent way, like metronidazole, whereas omeprazole had almost no effect on fumarate reductase. No other significant effects on the enzymes of the respiratory chain were found. The synergistic effect of nizatidine on metronidazole resistant H. pylori strains could be explained by the effect on fumarate reductase, whereas the effect of omeprazole is different and could be an inhibition of a proton pump in H. pylori. Reversal of antimicrobial resistance with the help of different non-antibiotics seems to be possible by using quite different compounds, and is therefore to be explained by different molecular mechanisms.

Childhood peptic ulcer in the Ural area of Russia: clinical status and Helicobacter pylori-associated immune response

BACKGROUND

The relation of between Helicobacter pylori and the symptoms in children is still controversial. Determination of specific immunoglobulin (Ig) G antibodies to H. pylori may represent a useful test to screen the patients with acid peptic disease in childhood. The aim of this study was to investigate the spectrum of clinical symptoms, endoscopic and histologic lesions, and clinical value of serum IgG response to H. pylori in school-aged children residing in the Ural area of Russia for the identification of Helicobacter -related acid-peptic disease.

METHODS

During 1998, 129 pediatric outpatients (mean age, 12.1 +/- 2.3 years; age range, 10-15 years; 41 boys, 88 girls) were undergoing gastroduodenal endoscopy for evaluation of chronic abdominal pain. H. pylori colonization was determined by histology, urease test, and polymerase chain reaction. H. pylori IgG antibodies were found by using an enzyme-linked immunosorbent assay.

RESULTS

There was a high prevalence of H. pylori infection (80%) and peptic ulcers (24%) among the study group. Duodenal ulcers were detected in 31 of the children; all of them were H. pylori positive. Family history of peptic ulcers, nighttime pain associated with nocturnal awakening, fasting pain relieved by food, pain associated with meals, postprandial pain, bitter taste, and heartburn were the clinical signs that helped to distinguish the ulcer-positive children from the ulcer-negative H. pylori group. Duodenal ulcer patients had higher anti- H. pylori IgG titers compared with the levels of IgG antibodies in the infected children without ulcers ( P < 0.001). Peptic ulcer disease was a more common finding in the Ural ethnic group of Asians (Bashkirs) compared with the pediatric population of Russian origin.

CONCLUSIONS

These results provide further evidence for a causal relation between H. pylori -associated peptic ulcer disease in childhood and relevant clinical symptoms. High titers of anti- H. pylori IgG might serve as a useful noninvasive indicator of ulcer disease.

Association of CagA-positive infection with Helicobacter pylori antibodies of IgA class

cagA gene, the best known virulence factor of Helicobacter pylori, codes for an immunodominant CagA protein. In this study, CagA antibodies of the IgG class were measured by immunoblot or enzyme immunoassay in subjects with positive H. pylori serology, and the presence of CagA antibodies was compared with that of H. pylori antibodies of IgA and IgG classes. Serum samples were available for a total of 1,481 subjects, including gastroscopied patients with biopsy-verified H. pylori infection, smoking men with a normal or low serum pepsinogen I level indicating atrophic corpus gastritis, and subjects who later developed gastric cancer and their matched controls. CagA antibodies were significantly more prevalent among individuals with elevated H. pylori antibody titres of the IgA class than in those with IgG antibodies only, with the exception of a small subgroup of individuals who later developed gastric cancer. CagA-positive H. pylori strains seem to induce an immune response with a markedly higher frequency of IgA than what is found in inflammation caused by CagA-negative strains. The presence of serum IgA antibodies to H. pylori seems to indicate a higher risk for CagA-positive H. pylori infection and possibly more severe late sequelae of the disease.

Recent developments in the epidemiology of Helicobacter pylori

Prevalence determinations have been performed around the world, and regardless of how exotic a location, H. pylori is found in a substantial proportion of the population. H. pylori remains among the most universal of infections. Understanding of some features of infection has changed. Infection can be gained and lost at rates higher than previously realized. Oral-oral and oral-fecal transmission account for most, if not nearly all, cases of infection. H. pylori infection has declined rapidly in developed countries, which probably has contributed to declines in duodenal ulcer disease and gastric cancer. The full health implications of the potential elimination of infection are unknown.

Seroconversion and seroreversion in IgG antibodies to Helicobacter pylori: a serology based prospective cohort study

STUDY OBJECTIVES

To assess the incidence of seroconversion and seroreversion in IgG antibodies to Helicobacter pylori within a 11 year observation period using these events as markers for acquisition and loss of the infection, respectively.

DESIGN

Population based prospective cohort study.

SETTING

Northern part of Copenhagen County, Denmark.

PARTICIPANTS AND METHODS

A random sample of 2527 Danish adults were examined and blood obtained in 1983 and in 1994. Matching pairs of sera were analysed for the presence of IgG and IgM antibodies to H pylori with an in house enzyme linked immunosorbent assay. Participants who were seronegative at study entry and seropositive at follow up and had a fourfold increase in baseline IgG antibody levels were categorised as seroconverters and regarded as having acquired H pylori infection. Participants who were seropositive at study entry and had at least a fourfold decrease in baseline IgG antibody levels at follow up were assumed to have lost the infection (seroreverters).

RESULTS

The seroprevalence of H pylori infection was 24.7 (95% confidence intervals (95% CI) 23.0, 26.4) % in 1983 and 24.5 (95% CI 22.8, 26. 2) % in 1994. A total of 14 participants seroconverted within the observation period (cumulative 11 year incidence proportion: 1.0 (95% CI 0.5, 1.5) %). Having increased IgM antibody levels at study entry significantly increased the likelihood of IgG seroconversion (relative risk 6.4 (95% CI 2.1, 19.6). Seroreversion was seen in 48 participants (cumulative 11 year incidence proportion: 7.7 (95% CI 5. 6, 9.8) %).

CONCLUSIONS

Changes in H pylori infection status with time are rare in Danish adults. Few adults become infected with H pylori in Denmark.

Potentiation of the action of metronidazole on Helicobacter pylori by omeprazole and bismuth subcitrate

Treatment failures using triple therapy that include metronidazole, are common in patients infected with metronidazole-resistant Helicobacter pylori in the gastric mucosa. Higher eradication rates in such patients have been described when treatment regimens include bismuth salts compared to regimens that include proton pump inhibitors. In the present study, the synergistic effect of subinhibitory concentrations (0.25-0.5 MIC) of either bismuth subcitrate or omeprazole with metronidazole on the susceptibility of 42 H. pylori strains was investigated by agar dilution method and the Epsilometer test (Etest). With 0.5 MIC of either of the two drugs, the susceptibility of all H. pylori4 mg/l) reverted to being metronidazole sensitive. These results suggested that either bismuth salts or proton pump inhibitors may be effective in the treatment of some infections with metronidazole-resistant H. pylori strains when used in sufficiently high doses.

Association of Helicobacter pylori infection with lifestyle, chronic disease, body-indices, and age at menarche in Danish adults

This study examines the association between lifestyle factors, chronic disease, body-indices, and the seroprevalence of Helicobacter pylori infection in Danish adults. The relationship between age at menarche and H. pylori infection is also assessed. A random sample of 3,608 Danish adults completed a questionnaire about lifestyle factors (smoking habits, alcohol consumption, and coffee and tea intake), doctor diagnosed chronic diseases (heart conditions, diabetes, chronic bronchitis, and hypertension), menarche, and socio-demographic factors. A total of 2,913 participants were eligible for the present study. Electrocardiographs were recorded and blood pressure and serum lipid levels (HDL cholesterol, triglyceride, and cholesterol) were measured. Height and weight were determined and body mass index (BMI) calculated. Sera were analysed with an enzyme-linked immunosorbent assay for the presence of H. pylori specific IgG antibodies. The seroprevalence of H. pylori infection was associated with weekly alcohol intake > or = 6 drinks (odds ratio 0.7, 95% confidence interval 0.6-0.9) due to a low rate of H. pylori infection among wine drinkers (odds ratio 0.6, 95% confidence interval 0.5-0.7). No associations were found with smoking habits or serum lipids. People with upper quartile BMI (> or = 26.8 kg/m2) were more likely to be seropositive for antibodies to H. pylori (odds ratio 1.6, 95% confidence interval 1.1-2.4). Chronic bronchitis (odds ratio 1.6, 95% confidence interval 1.1-2.5) and unspecified heart condition (odds ratio 2.0, 95% confidence interval 1.1-3.3) was more often seen in IgG seropositive women than in uninfected women. The likelihood of being seropositive for IgG antibodies to H. pylori increased with age at menarche (odds ratio per year 1.10, 95% confidence interval 1.02-1.19). Previously reported associations with age and socioeconomic status were confirmed. We conclude that wine drinking is associated with lower rates of H. pylori infection in Danish adults. The seroprevalence of H. pylori infection is increased in people with high BMI. H. pylori infection may relate to a history of late menarche and chronic bronchitis in Danish women.

Serum ferritin, hemoglobin, and Helicobacter pylori infection: a seroepidemiologic survey comprising 2794 Danish adults

BACKGROUND & AIMS

Helicobacter pylori infection was recently associated with iron-deficiency anemia. The aim of this study was to examine the relationship between H. pylori infection, hemoglobin, and iron status using serum ferritin as a marker for total body iron.

METHODS

Serum ferritin, hemoglobin, and immunoglobulin G (IgG) antibodies against H. pylori were assessed in 2794 Danish adults who attended a population survey. IgG antibodies were measured with an in-house enzyme-linked immunosorbent assay, serum ferritin with an immunoradiometric assay, and hemoglobin with Coulter-S.

RESULTS

The seroprevalence of H. pylori infection did not relate to hemoglobin. Serum ferritin levels were significantly lower in men (114 vs. 120 microg/L; P = 0.01) and in postmenopausal women (63 vs. 77 microg/L; P = 0.02) who were IgG positive than in seronegative individuals. IgG-positive people more often had reduced serum ferritin levels (</=30 microg/L) than seronegative people. This association persisted in multivariate analysis after adjusting for possible confounding factors (odds ratio, 1.4; 95% confidence interval 1.1-1. 8).

CONCLUSIONS

Serum ferritin levels are reduced in people with increased IgG antibodies to H. pylori. H. pylori infection affects iron metabolism in humans.

Helicobacter pylori and gastric cancer in Croatia

The seroprevalence of Helicobacter pylori infection was studied in a population from two areas of Croatia with significantly different average gastric cancer (GC) cumulative incidence and mortality rates. In a random sample of 456 blood sera from both areas, which was tested with the ELISA Helicobacter pylori-antibody test, 48.8% of people in the north and 53.3% in the south of the country were found to be infected. The difference between the two areas in the seroprevalence of the infection was not statistically significant, nor did their populations differ in age, sex, educational background, smoking habit or wine consumption. Our results do not point to any association between the prevalence of Helicobacter pylori infection and the level of cumulative incidence and GC mortality levels.

Helicobacter pylori infection in patients with chronic pancreatitis and duodenal ulcer

BACKGROUND

The prevalence of duodenal ulcer is high in patients with chronic pancreatitis. Patients with simple duodenal ulcer without chronic pancreatitis are mostly Helicobacter pylori-infected, and the prevalence of IgG seropositivity is > 95%. The prevalence of H. pylori infection in patients with chronic pancreatitis is not known.

METHODS

IgG antibodies against H. pylori were measured in a cross-sectional survey of consecutive patients who had their exocrine pancreas function examined with a Lundh meal test in the period 1988-95 and in a control group of patients with simple duodenal ulcer.

RESULTS

Twenty-seven per cent of the patients with chronic pancreatitis had duodenal ulcer during the observation period. The prevalence of IgG antibodies against H. pylori was 22% in patients with chronic pancreatitis without duodenal ulcer as compared with 27% with non-organic abdominal pain. The prevalence of IgG antibodies against H. pylori was 60% in patients with chronic pancreatitis complicated by duodenal ulcer as compared with 86% in controls with simple duodenal ulcer.

CONCLUSIONS

H. pylori infection contributes but may not be the only cause of duodenal ulcer in patients with chronic pancreatitis.

The effect of cimetidine on ethanol concentrations in fasting women and men after two different doses of alcohol

BACKGROUND

Serum ethanol concentrations may become higher when alcohol is consumed during treatment with histamine receptor antagonists, especially if ethanol is ingested postprandially. Only a few studies have investigated fasting subjects, and women have only been investigated sporadically.

METHODS

The present study compared serum ethanol concentrations after a 4-h fast followed by a low (0.15 g/kg) and a high (0.45 g/kg) dose of ethanol, on two separate occasions in six women and six men. The study was carried out before and after treatment with 400 mg cimetidine twice daily.

RESULTS

Cimetidine administration did not change the area under the concentration-time curve or the maximal serum ethanol concentration in either women or men, irrespective of ethanol dose. Ethanol elimination rate was unchanged by cimetidine.

CONCLUSION

Cimetidine does not influence the ethanol concentration-time curve when ethanol is ingested on an empty stomach.