Relation between infection with Helicobacter pylori and living conditions in childhood: evidence for person to person transmission in early life

Association of Helicobacter pylori infection with reduced risk for esophageal cancer is independent of environmental and genetic modifiers

BACKGROUND & AIMS

Infection with Helicobacter pylori is associated with reduced risk of esophageal adenocarcinoma (EAC), but it is not clear whether this reduction is modified by genotype, other host characteristics, or environmental factors. Furthermore, little is known about the association between H pylori and adenocarcinomas of the esophagogastric junction (EGJAC) or squamous cell carcinomas (ESCC). We sought to measure the association between H pylori infection and esophageal cancer and identify potential modifiers.

METHODS

In an Australian, population-based, case-control study, we compared the prevalence of H pylori seropositivity and single nucleotide polymorphisms in interleukin (IL)-1B (-31, -511) and tumor necrosis factor (TNF)-alpha (-308, -238) among 260 EAC, 298 EGJAC, and 208 ESCC patients and 1346 controls. To estimate relative risks, we calculated odds ratios (OR) and 95% confidence intervals (CI) using multivariable logistic regression in the entire sample and within strata of phenotypic and genotypic risk factors.

RESULTS

H pylori infection was associated with significantly reduced risks of EAC (OR, 0.45; 95% CI: 0.30-0.67) and EGJAC (OR, 0.41; 95% CI: 0.27-0.60) but not ESCC (OR, 1.04; 95% CI: 0.71-1.50). For each cancer subtype, risks were of similar magnitude across strata of reflux frequency and smoking status. We found no evidence that polymorphisms in IL-1B or TNF-alpha modified the association between H pylori and EAC or EGJAC.

CONCLUSIONS

H pylori infection is inversely associated with risks of EAC and EGJAC (but not ESCC); the reduction in risk is similar across subgroups of potential modifiers.

Seroprevalence of Helicobacter pylori infection among children of low socioeconomic level in São Paulo

CONTEXT AND OBJECTIVE

Helicobacter pylori infection is mainly acquired during childhood, and is associated with significant morbidity in adults. The aim here was to evaluate the seroprevalence and risk factors of H. pylori infection among children of low socioeconomic level attended at a public hospital in São Paulo, Brazil.

DESIGN AND SETTING

Cross-sectional study, among patients attended at an outpatient clinic.

METHODS

326 children were evaluated (150 boys and 176 girls; mean age 6.82 ± 4.07 years) in a cross-sectional study. Patients with chronic diseases or previous H. pylori treatment, and those whose participation was not permitted by the adult responsible for the child, were excluded. The adults answered a demographic questionnaire and blood samples were collected. The serological test used was Cobas Core II, a second-generation test. Titers > 5 U/ml were considered positive.

RESULTS

H. pylori infection was diagnosed in 116 children (35.6%). Infected children were older than uninfected children (7.77 ± 4.08 years versus 5.59 ± 3.86 years; p < 0.0001). The seroprevalence increased from 20.8% among children aged two to four years, to 58.3% among those older than 12 years. There were no significant relationships between seropositivity and gender, color, breastfeeding, number of people in the home, number of rooms, bed sharing, living in a shantytown, maternal educational level, family income or nutritional status. In multivariate analysis, the only variable significantly associated with H. pylori seropositivity was age.

CONCLUSION

Infection had intermediate prevalence in the study population, and age was associated with higher prevalence.

Neither genotype nor the gastric colonization site of Helicobacter pylori are predictive factors for the development of erosive esophagitis in patients with peptic ulcer disease, 1 year after eradication

CONTEXT

Whether Helicobacter pylori infection is a protective or predisposing factor for the development of gastroesophageal reflux disease remains controversial. The most virulent strains, such as those expressing the cytotoxin-associated gene A (CagA), and the site of gastric colonization have been correlated with the prevention or development of esophagitis.

AIM

To determine the incidence of erosive esophagitis following eradication of H. pylori in patients with peptic ulcer disease and to evaluate the association of erosive esophagitis with virulent strains of H. pylori and the site of gastric colonization.

METHODS

Triple therapy with lansoprazole, amoxicillin and clarithromycin was administered to 159 patients with peptic ulcer disease. Endoscopy, histopathology, urease and carbon-14 urea breath tests were performed prior to treatment, at 3 months and 1 year following treatment. Genotyping of H. pylori strains using polymerase chain reaction was performed separately on samples from the corpus and antrum.

RESULTS

One year after treatment, 148 successfully treated patients were reevaluated. Twenty-eight patients (19%) had erosive esophagitis, classified as Los Angeles grade A in 24 and B in 4. The samples taken from the corpus were CagA-positive in 18 patients (64%), while the samples taken from the antrum were CagA-positive in 21 patients (75%).

CONCLUSIONS

The incidence of erosive esophagitis in peptic ulcer patients who had their H. pylori eradicated was 19%. No correlation was found between the gastric site colonized by H. pylori or strains expressing CagA and the prevention or development of erosive esophagitis in patients with peptic ulcer disease, 1 year after infection eradication.

Demography of aging and the epidemiology of gastrointestinal disorders in the elderly

Population aging is a global phenomenon. It is estimated that there were 600 million people in the world aged 60 and over in 2000 and that there will be 1.2 billion by 2025. People aged 65 and over comprise 16% of the population of Europe. About half of the world's elderly population live in the developing world. Many of the gastrointestinal disorders seen in specialist practise show age-specific incidence and prevalence rates that increase substantially with increasing age. In this review, hospitalization rates for gastroenterological disorders in England are presented by age to demonstrate gradients with age. Some of the disorders, such as colorectal cancer, appendicitis, diverticular disease and inflammatory bowel disease, became common in developed countries in association with economic development and changes in lifestyle. As the developing world becomes more urbanised and westernised, disorders that are now rare in the developing world will probably become much more common.

Sibship size, Helicobacter pylori infection and chronic atrophic gastritis: a population-based study among 9444 older adults from Germany

BACKGROUND

Early-life social environment has been suggested to play an important role during the development of Helicobacter pylori-related gastric diseases. We aimed to assess the association of sibship size with H. pylori infection and chronic atrophic gastritis (CAG) in a population-based study from Germany.

METHODS

In the baseline examination of ESTHER, a study conducted in Saarland, serological measurements of pepsinogen I and II and H. pylori antibodies were taken in 9444 participants aged 50-74 years. Information on potential risk factors and medical history were obtained by self-administered standardized questionnaire.

RESULTS

A strong dose-response relationship between sibship size and H. pylori seroprevalence was observed (P < 0.01). Adjusted odds ratios (ORs) 95% confidence interval (CI) for H. pylori seropositivity for subjects with 4, 5, 6 and 7 or more siblings compared with subjects without siblings were 1.45 (1.20-1.77), 1.83 (1.50-2.22) and 1.84 (1.47-2.31), respectively. A large sibship size was also associated with an increased risk of CAG with an adjusted OR of 1.42 (1.01-2.01) for 7 or more compared with less than or equal to 2 siblings. This association was attenuated but not entirely eliminated after additional adjustment for H. pylori infection. Notably, a significant association between large sibship size and CAG was also found among H. pylori-negative subjects.

CONCLUSIONS

Our results suggest that large sibship size is associated with increased H. pylori prevalence and CAG risk. The association with CAG risk may be mediated at least in part by H. pylori infection. However, mechanisms other than H. pylori infection may contribute to the 'sibling effect' as well.

Gastroenterology in developing countries: issues and advances

Developing countries shoulder a considerable burden of gastroenterological disease. Infectious diseases in particular cause enormous morbidity and mortality. Diseases which afflict both western and developing countries are often seen in more florid forms in poorer countries. Innovative techniques continuously improve and update gastroenterological practice. However, advances in diagnosis and treatment which are commonplace in the West, have yet to reach many developing countries. Clinical guidelines, based on these advances and collated in resource-rich environments, lose their relevance outside these settings. In this two-part review, we first highlight the global burden of gastroenterological disease in three major areas: diarrhoeal diseases, hepatitis B, and Helicobacter pylori. Recent progress in their management is explored, with consideration of future solutions. The second part of the review focuses on the delivery of clinical services in developing countries. Inadequate numbers of healthcare workers hamper efforts to combat gastroenterological disease. Reasons for this shortage are examined, along with possibilities for increased specialist training. Endoscopy services, the mainstay of gastroenterology in the West, are in their infancy in many developing countries. The challenges faced by those setting up a service are illustrated by the example of a Nigerian endoscopy unit. Finally, we highlight the limited scope of many clinical guidelines produced in western countries. Guidelines which take account of resource limitations in the form of "cascades" are advocated in order to make these guidelines truly global. Recognition of the different working conditions facing practitioners worldwide is an important step towards narrowing the gap between gastroenterology in rich and poor countries.

Infection by Helicobacter pylori in Bangladeshi children from birth to two years: relation to blood group, nutritional status, and seasonality

BACKGROUND

A birth cohort of 238 children was followed in an urban slum in Dhaka, Bangladesh, to determine incidence, prevalence, and epidemiologic factors related to Helicobacter pylori infection.

METHODS

H. pylori infection was determined by a specific stool antigen test as well as enzyme-linked immunosorbent assay for detecting specific IgA and IgG antibodies in sera in children who completed 2 years of follow-up.

RESULTS

Using the stool antigen test and serology, 50% and 60% of infants respectively, were positive for H. pylori by 2 years; an increase in the infection rate was seen after 6 months of age. Determination of specific antibodies in sera and detection of H. pylori antigen in stool were comparable. A typical seasonality, peaking in spring and autumn, was observed for acquisition of initial H. pylori infection. Children with blood group "A" were more susceptible to H. pylori infection than those with other ABO blood groups. Malnutrition did not seem to promote colonization by H. pylori. However, H. pylori-infected children were more often infected by multiple enteropathogens, often isolated at different time points.

CONCLUSIONS

This study shows that noninvasive diagnostic methods such as serology and the stool antigen test are suitable for the study of acquisition of H. pylori infections in infants and can be used in field settings as well as in laboratories and clinical setting having less well equipped facilities. The study also shows seasonality for initial H. pylori infection and a relationship between blood group "A" and infection.

Childhood hygienic practice and family education status determine the prevalence of Helicobacter pylori infection in Iran

BACKGROUND

Management of Helicobacter pylori, a causative agent of gastrointestinal diseases is an important health problem in most countries. The main reasons include poorly defined epidemiological status and unrecognized mode of bacterial transmission. Our objective was to investigate the prevalence of H. pylori infection in a representative population of Iran and to evaluate possible risk factors for the H. pylori infection.

MATERIALS AND METHODS

In this cross-sectional study, 2561 healthy individuals aged 18-65 years (mean age, 35.5 years) were selected out of 12,100,000 inhabitants of Tehran province by cluster sampling. Infection with H. pylori was evaluated by detection of anti-H. pylori IgG antibody in serum. Sociodemographic status of each subject was determined by filling up a questionnaire.

RESULTS

Prevalence of H. pylori infection was 69% and was correlated with increasing age. The highest infection rate (79.2%) was seen in individuals 46-55 years old. No association was detected between H. pylori positivity and gender. Low education of the study subjects; low father's and mother's education; poor tooth brushing habit; crowded families in childhood; and lack of household bath, hygienic drinking water, and swage disposal facility in childhood were determined as possible risk factors.

CONCLUSIONS

The rate of prevalence of H. pylori infection was higher than developed countries. Low socioeconomic status, poor sanitary indications, and crowded families in childhood were related to high prevalence of H. pylori infection in Iran. Accordingly, fecal-oral and oral-oral routes could be considered as the main pathways of transmission of H. pylori.

Acquisition of Helicobacter pylori infection in early childhood: independent contributions of infected mothers, fathers, and siblings

OBJECTIVES

Infected siblings, mothers, and fathers have all been suggested to be major sources for Helicobacter pylori acquisition among children, but few studies have addressed the potential role of various family members simultaneously.

METHODS

A systematic review was performed on studies investigating intrafamilial transmission of childhood H. pylori infection. Within the Ulm Birth Cohort Study, which consists of 1,066 healthy newborns, born between November 2000 and November 2001 and followed up to age 4, and their siblings and parents, the independent role of the infection status of parents and siblings in transmission of H. pylori among children at age 4 was assessed.

RESULTS

Among four studies reporting infected mothers and siblings as independent risk factors for childhood H. pylori infection, odds ratios (ORs) for childhood infection given an infected sibling decreased meaningfully after adjustment for maternal infection status. Within the Ulm Birth Cohort Study, the prevalence of infection was 3.0% among index children at age 4. In bivariate analyses, maternal, paternal, and sibling infection were all strongly and significantly related to infection of the child. However, after multivariate adjustment, only maternal infection persisted as the single strong and significant risk factor (OR 13.0, 95% confidence interval 3.0-55.2).

CONCLUSIONS

These patterns suggest that mutual control for H. pylori status of other family members is crucial for estimating the role of mothers, fathers, and siblings in the transmission of childhood H. pylori infection. In populations with low H. pylori prevalence the infected mother is likely to be the main source for childhood H. pylori infection.

Migrant communities constitute a possible target population for primary prevention of Helicobacter pylori-related complications in low incidence countries

OBJECTIVE

Pre-selection of individuals with epidemiological risk factors for Helicobacter pylori infection and atrophic gastritis could increase the efficiency of serologic screening to prevent peptic ulcer disease and gastric cancer in Western countries. The aim of this study was to determine the prevalence of and risk factors for H. pylori infection and atrophic gastritis in a migrant community in The Netherlands.

MATERIAL AND METHODS

Inhabitants from an urban district in Rotterdam, The Netherlands with a large proportion of immigrants were randomly selected. Information was collected on demographic factors, socio-economic status, lifestyle, history of dyspeptic symptoms and medication use. In addition, serologic H. pylori and CagA status and the presence of atrophic gastritis were evaluated.

RESULTS

In total, 288 subjects were included. Surinamese or Antillean, Turkish, Cape Verdian and Moroccan subjects were H. pylori-infected in 65%, 82%, 86% and 96% of cases, respectively, whereas the infection rate in Dutch subjects was 46% (all p<0.05). Within multivariate logistic regression analysis, ethnicity and number of persons in a household were identified as independent risk factors for H. pylori infection. In addition, mean pepsinogen I level and pepsinogen I/II ratio were significantly lower in subjects of non-Dutch origin as compared to Dutch subjects (both p<0.001). No Dutch subjects suffered from atrophic gastritis, as compared with 12 subjects of non-Dutch origin (p=0.13).

CONCLUSIONS

The prevalence of H. pylori is high in migrant populations in The Netherlands. Furthermore, markers of atrophic gastritis are increased in subjects of foreign origin. Therefore, these migrant communities may constitute a target group for serologic screening to prevent H. pylori-related complications in Western countries.

The seroepidemiology of Helicobacter pylori infection in Australia

BACKGROUND

Infection with Helicobacter pylori is common worldwide and a significant cause of upper gastrointestinal disease. Prevalence of this infection varies in different population groups internationally. Because of the invasiveness of specimen collection for bacteriologic diagnosis and the expense of tests such as labeled urea breath tests, serology is the most feasible means of determining the population epidemiology of H. pylori. The aim of this study was to describe the seroepidemiology of H. pylori infection in Australia.

METHODS

H. pylori-specific ELISA for the presence of IgG antibodies was performed on a representative sample of 2413 sera from Australia in 2002, using validated serosurveillance methods.

RESULTS

The overall seroprevalence of H. pylori infection in Australia was 15.1% in 2002, with no statistical difference between genders. Seropositivity rates increased progressively with age, ranging between 4.0% in the 1-4-year-olds and 23.3% in the 50-59-year-olds.

CONCLUSIONS

The prevalence of infection with H. pylori in Australia was lower than rates reported in other developed countries, at 15.4%. This study provides important baseline measurements for future preventive measures including vaccine research and development. Further studies to determine subgroups at higher risk of infection may help target the more susceptible populations.

Helicobacter pylori gastritis, the unifying concept for gastric diseases

Helicobacter pylori infection causes a broad spectrum of clinical diseases and the clinical manifestations of the infection depend on host, environmental, and bacterial factors. These factors have an impact on the pattern and severity of gastritis and ultimately determine the clinical outcome of H. pylori infection. Better staging of gastritis may help to identify patients at risk of gastric cancer. In this article we will examine the complex interaction between host, environmental, and bacterial factors in the pathogenesis of H. pylori infection.

Effect of sibling number in the household and birth order on prevalence of Helicobacter pylori: a cross-sectional study

BACKGROUND

Infection with Helicobacter pylori (H. pylori) is acquired mainly in childhood, with studies demonstrating this is related to living conditions. Effects of sibling number and birth order on prevalence of infection have not been extensively studied.

METHODS

The authors performed a cross-sectional survey of adults, aged between 50 and 59 years, previously involved in a community-screening programme for H. pylori in Leeds and Bradford, UK. Prevalence of H. pylori was assessed at baseline with urea breath test. All individuals who were alive, and could be traced, were contacted by postal questionnaire in 2003 obtaining information on number of siblings and birth order. Data concerning childhood socioeconomic conditions were stored on file from the original study.

RESULTS

3928 (47%) of 8407 original participants provided data. Prevalence of infection increased according to sibling number (20% in those with none vs 63% with eight or more). Controlling for childhood socioeconomic conditions and birth order using multivariate logistic regression, infection odds were substantially increased with three siblings compared with none [odds ratio (OR) 1.51; 95% confidence interval (CI) 1.06-2.15], and a gradient of effect continued up to eight or more siblings (OR 5.70; 95% CI 2.92-11.14). Odds of infection also increased substantially with birth order, but the positive gradient disappeared on adjustment for sibling number and childhood socioeconomic conditions.

CONCLUSIONS

: In this cross section of UK adults, aged 50-59 years, sibling number in the household, but not birth order, was independently associated with prevalence of H. pylori infection.

Seroprevalence of Helicobacter pylori and cagA antibodies in Iceland, Estonia and Sweden

The public health implications from H. pylori infection are considerable but the transmission routes are largely unknown. In this study, the prevalence, patient characteristics and risk factors for Helicobacter pylori infection were comparatively investigated in Iceland, Sweden and Estonia. Blood samples were collected from 1046 subjects aged approximately 25-50 y (447 in Reykjavik, 359 in Uppsala and 240 in Tartu) for determination of antibodies to H. pylori and its cagA protein. The prevalence of H. pylori antibodies was 69% in Tartu, 36% in Reykjavik and 11% in Uppsala (p<0.0001). There was an increase in prevalence with age in Iceland and Sweden but not in Estonia. The prevalence of antibodies to the cagA protein in subjects seroreactive to H. pylori was lower in Reykjavik (36%) than in Uppsala (69%) and Tartu (62%) (p<0.0001). H. pylori infection, as determined by seroreactivity, was positively associated with smoking and BMI. Overall, socioeconomic development during the childhood period seems to be the most important factor for the prevalence of H. pylori infection. In adults, smoking may be a contributory factor.

Prevalence of Helicobacter pylori infection among Egyptian children: impact of social background and effect on growth

OBJECTIVE

The study aim was to assess the prevalence of Helicobacter pylori infection in Egyptian schoolchildren and its effect on growth parameters.

DESIGN

A cross-sectional population-based study was conducted among 286 schoolchildren (168 boys and 118 girls), with a mean age of 11.04 +/- 0.19 years, to determine the prevalence of H. pylori. The presence of the bacterium was assessed using the [13C]urea breath test. Relevant personal and socio-economic data on risk factors for infection were collected. Height and weight were analysed in relation to H. pylori infection.

RESULTS

The overall prevalence of H. pylori infection was 72.38%. Attending school in a socially deprived area and residing in an overcrowded home were the major risk factors for infection. Differences between infected and non-infected children were significant with regard to body weight and height (weight: 39.5 +/- 1.0 vs. 44.6 +/- 1.8 kg, P = 0.05; height: 139.9 +/- 1.3 vs. 144.2 +/- 2.1 cm; P = 0.009). The number of children (both boys and girls) falling below the 5th percentile of height-for-age was significantly higher in infected than non-infected children (P = 001), similarly for Z-scores for height-for-age below -2.0 (P = 0.003).

CONCLUSION

The results demonstrate not only that the prevalence of H. pylori infection is extremely high among Egyptian schoolchildren, but also that the adverse effects of the infection reach far beyond the stomach. Evidence of the burden of infection on growth failure is presented.

Immune and proliferative cellular responses to Helicobacter pylori infection in the gastric mucosa of Mexican children

BACKGROUND

Helicobacter pylori infection occurs mostly during childhood, but few studies on this age group have addressed the innate immune and the proliferative response to this infection. Mexico has a high H. pylori prevalence in children, but a low risk of gastric cancer. The aim of this work was to study the cellular responses of the gastric mucosa to this infection in Mexican children.

METHODS

Antral and corpus gastric biopsies were obtained from 44 H. pylori-infected children (mean age 12 +/- 3.2 years) and 44 uninfected children (mean age 10 +/- 3 years). Mucosal cellular responses were studied by immunohistochemistry, using anti-Ki67 antibodies for proliferation studies, antihuman tryptase for mast cells, and antihuman CD68 for macrophages. T and B lymphocytes were stained with a commercial integrated system. The intensity of cellular responses was estimated histologically using the software KS300.

RESULTS

Epithelium proliferation and infiltration of macrophages and T and B lymphocytes were significantly higher in H. pylori-infected than in uninfected children. A balanced increase of CD4, CD8, and CD20 lymphocytes was observed in infected children. However, activated mast cells were decreased, and infiltration of neutrophil and mononuclear cells was low. Epithelial proliferation was associated with polymorphonuclear infiltration but not with infiltration of macrophages or lymphocytes. Inflammation and proliferation was higher in CagA (+)-infected children.

CONCLUSIONS

Mexican children respond to H. pylori infection with a low inflammatory response, a balanced increase of T and B lymphocytes, and a high regenerative activity.

Who consults with dyspepsia? Results from a longitudinal 10-yr follow-up study

OBJECTIVE

Dyspepsia is common, and the condition is often chronic, with a relapsing and remitting nature. Factors influencing the decision to consult a physician with symptoms remain unclear.

METHODS

The authors conducted a 10-yr follow-up longitudinal survey of individuals originally involved in a community-screening program for Helicobacter pylori (H. pylori). All surviving, traceable participants were contacted by validated postal dyspepsia questionnaire. Baseline demographic data, dyspepsia and irritable bowel syndrome (IBS) symptom data, and quality of life at study entry were already on file. Consent to examine primary care records was requested, and data regarding nonsteroidal anti-inflammatory drug and aspirin use, and dyspepsia and IBS-related consultations over the 10-yr study period were extracted from these.

RESULTS

Of 8,407 individuals originally involved, 3,266 (39%) gave consent to examination of primary care records. The mean age of included individuals was 55 yr, and 1,467 (45%) were male. 1,738 (53%) had dyspepsia, and 729 (42%) of these consulted a primary care physician as a result. Following multivariate logistic regression, H. pylori infection (odds ratio [OR] 1.76, 99% confidence interval [CI] 1.30-2.39), lower socioeconomic status (OR 1.68, 99% CI 1.02-2.76), frequent (OR 2.61, 99% CI 1.69-4.01) or severe (OR 1.87, 99% CI 0.99-3.52) symptoms, and increasing age (OR per year 1.06, 99% CI 1.0-1.11) were independent risk factors for consultation.

CONCLUSIONS

Reasons for consulting a physician with dyspepsia are multifactorial, but H. pylori infection, lower socioeconomic status, frequent or severe symptoms, and increasing age are independent predictors of consultation.

Number of siblings and the risk of solid tumours: a nation-wide study

We analysed the effects of number of siblings on the risk of solid tumours using the Swedish Family-Cancer Database, including population-based information on over 11 million individuals and more than 178 000 cancer patients diagnosed between 1958 and 2004. Incidence rate ratios (RRs), estimated by Poisson regression models, were adjusted for age, sex, birth cohort, area of residence and socioeconomic status. Having eight or more siblings vs none increased the risk of stomach cancer (RR=1.83, 95% confidence interval (CI), 1.44–2.34). Anal cancer diagnosed before age 40 showed the strongest association with the total siblings (RR=3.27, 95% CI, 2.04–5.26 for five or more siblings vs none). Endometrial (RR=0.76, 95% CI, 0.70–0.82), testicular (RR=0.71, 95% CI, 0.62–0.82), skin cancer (RR=0.82, 95% CI, 0.69–0.97) and melanoma (RR=0.72, 95% CI, 0.65–0.79) showed strong decreased risks for five or more siblings vs none. Prostate cancer risk for those with five or more older siblings vs none was 1.38 (95% CI, 1.23–1.55). Having five or more younger siblings was most strongly associated with stomach cancer (RR=1.59, 95% CI, 1.29–1.95) and melanoma (RR=0.68, 95% CI, 0.59–0.79). We conclude that sibship characteristics are strong correlates of cancer risk at several sites; plausible interpretations include socioeconomic status.

Intrafamilial transmission of Helicobacter pylori among the population of endemic areas in Japan

BACKGROUND

Helicobacter pylori (H. pylori) infection is a worldwide phenomenon related to several gastrointestinal diseases. However, because many aspects concerning the route of transmission remain unclear, we performed this epidemiologic study to clarify the route of intrafamilial transmission of H. pylori.

MATERIALS AND METHODS

A retrospective study was performed in three widely separate areas in Japan to investigate the prevalence of H. pylori infection. In 1993, 613 residents were tested as were 4136 in 2002, including 1447 family members of 625 families. Antibody to H. pylori (anti-H. pylori) was determined by enzyme-linked immunosorbent assay.

RESULTS

In 2002, the age-adjusted anti-H. pylori prevalence in Hoshino Village (67.5%) was significantly higher than in Kasuya Town (55.0%) and in Ishigaki City (54.7%) (p < .0001, p = .0039, respectively). The age-adjusted anti-H. pylori prevalence of Ishigaki City significantly decreased from 1993 (68.4%) to 2002 (52.5%), showing an age cohort effect. However, the prevalence did not significantly differ in children aged 0-6 years of Ishigaki City between 1993 (9.6%) and 2002 (10.3%). A familial analysis in 2002 demonstrated that the prevalence of anti-H. pylori was significantly higher in children with anti-H. pylori-positive (21.6%, 22 of 102) than with -negative mothers (3.2%, 3 of 95) (p < .0001, by Mantel-Haenszel test), whereas there was no significant difference between children with anti-H. pylori-positive and -negative fathers. Moreover, the prevalence was significantly higher in wives with anti-H. pylori-positive (64.0%, 208 of 325) than with -negative husbands (46.5%, 80 of 172) (p = .0071, by Mantel-Haenszel test) and in husbands with anti-H. pylori-positive (72.2%, 208 of 288) than with -negative wives (56.0%, 117 of 209) (p = .0106, by Mantel-Haenszel test).

CONCLUSIONS

In the last decade, H. pylori infection decreased in the general population of Japan by improvement of general hygiene conditions, but did not differ in young children, most likely because of mother-to-child transmission.

Helicobacter pylori and benign upper digestive disease

Acute infection with Helicobacter pylori causes hypochlorhydria and gastrointestinal upset. As the infection persists, patients develop chronic antral-predominant or pangastritis. Gastric and duodenal ulcers arise from chronic mucosal inflammation and disordered acid secretion in the stomach. With successful eradication of H. pylori, non-NSAID-related gastric and duodenal ulcers heal even without long-term acid suppression. More importantly, peptic ulcers and their complications rarely recur. Clearing H. pylori infection also reduces the risk of mucosal injury in NSAID and aspirin users; the protective effects are more pronounced in NSAID-naïve and aspirin users. H. pylori is unlikely to be the cause of gastro-oesophageal reflux disease. However, a patient's reflux symptoms may be more difficult to control after clearing the infection. Although there is little evidence to support a causal relationship between H. pylori and non-ulcer dyspepsia, treatment of the infection gives a modest improvement of symptoms.

Childhood Helicobacter pylori infection and growth impairment in developing countries: a vicious cycle?

We hypothesize that infection with the gastric pathogen Helicobacter pylori in children in developing countries is the initiator of a vicious cycle of events that result ultimately in malnutrition and growth impairment. Acute infection with H. pylori is accompanied by hypochlorhydria, which facilitates the acquisition of other enteropathogens because of removal of the gastric acid barrier, which then results in diarrheal disease and iron-deficiency anemia. This is likely to occur most frequently in developing regions where the prevalence of H. pylori infection is disproportionately high and multiple enteric coinfections are common. The consequent synergistic impact of diarrheal disease and micronutrient deficiency on growth and cognitive function in children has significant public health implications for socioeconomic development in these countries.

Community-based familial study of Helicobacter pylori infection among healthy Japanese Brazilians

BACKGROUND

The present study of Helicobacter pylori infection was conducted in family units of Japanese Brazilians living in São Paulo city. The authors attempted to determine the seroprevalence of H. pylori infection within family units of Japanese Brazilians and to identify risk factors associated with intrafamilial transmission.

METHODS

The seroprevalence was determined in 1037 healthy and asymptomatic volunteer subjects aged 0-69 years (530 adults and 507 children) of 265 families. Demographic data and details of living conditions were obtained from each family.

RESULTS

H. pylori seropositive infection was found in 39.2% of the parents and 9.3% of the children. A reduced risk of H. pylori infection was found for girls (odds ratio [OR] 0.45; 95% confidence interval [CI], 0.23-0.86). The prevalence of infection was 3.5% for children with uninfected parents; 9.9% (OR, 2.51; 95% CI, 0.95-6.61) for those with a seronegative mother and a seropositive father; 14.9% (OR, 4.93; 95% CI, 1.86-13.06) for those with a seropositive mother and a seronegative father; and 16.0% (OR, 5.29; 95% CI, 1.98-14.14) for those with seropositive parents. On multivariate analysis, the use of a pacifier, and mother's symptoms of nausea and vomiting were significantly associated with the risk of H. pylori infection for children, and the child having her/his own room was significantly associated with a reduced risk. Income was not associated with H. pylori infection in children and was inversely associated in parents.

CONCLUSION

The prevalence of H. pylori infection in family units of Japanese Brazilians supports the hypothesis of a predominant role for mother-child transmission of H. pylori infection, mainly through contact with regurgitated gastric juice in the mother's mouth.

Gastroenteritis and transmission of Helicobacter pylori infection in households

The mode of transmission of Helicobacter pylori infection is poorly characterized. In northern California, 2,752 household members were tested for H. pylori infection in serum or stool at a baseline visit and 3 months later. Among 1,752 person considered uninfected at baseline, 30 new infections (7 definite, 7 probable, and 16 possible) occurred, for an annual incidence of 7% overall and 21% in children <2 years of age. Exposure to an infected household member with gastroenteritis was associated with a 4.8-fold (95% confidence interval [CI] 1.4-17.1) increased risk for definite or probable new infection, with vomiting a greater risk factor (adjusted odds ratio [AOR] 6.3, CI 1.6-24.5) than diarrhea only (AOR 3.0, p = 0.65). Of probable or definite new infections, 75% were attributable to exposure to an infected person with gastroenteritis. Exposure to an H. pylori-infected person with gastroenteritis, particularly vomiting, markedly increased risk for new infection.

Helicobacter pylori occurrence and transmission: a family affair?

About half of the world's population is estimated to be infected with Helicobacter pylori, a gastric bacterium that contributes to the development of peptic ulcer disease and gastric cancer. H. pylori is more prevalent in low-income areas of the world and social and economic development decreases the prevalence as reflected in comparisons both within and between countries. The infection is typically acquired in early childhood and once established commonly persists throughout life unless treated. Person-to-person transmission within the family appears to be the predominant mode of transmission, particularly from mothers to children and among siblings, indicating that intimate contact is important. The route of transmission is uncertain, but the gastro-oral, oral-oral and faecal-oral routes are likely possibilities. Hence, gastroenteritis may facilitate dissemination of the infection. The community and environment may play additional roles for H. pylori transmission in some (low-income) settings. Furthermore, host and bacterial factors may modify the probabilities of acquisition and persistence of the infection. The understanding of H. pylori occurrence and transmission is of practical importance if future study deems prevention of the infection desirable in some high-prevalence populations. The present paper reviews aspects of H. pylori occurrence and transmission with an emphasis on household factors.

The mother as source of Helicobacter pylori infection

BACKGROUND

To further elucidate the intrafamilial transmission of Helicobacter pylori infection, we investigated the occurrence of infection by parental infection status in a large community-based birth cohort of children from Germany.

METHODS

Parental infection (at birth) and children's infection (at age 3 years) were determined by C-urea breath test and by monoclonal antigen stool test.

RESULTS

Twenty of 834 children (2.4%) were found to be infected. The odds ratio for H. pylori infection of the child was 12.9 (95% confidence interval = 3.2-52.5) if the mother was infected and 1.4 (0.4-4.6) if the father was infected, after adjustment for infection status of the other parent and for nationality. The number of older siblings was not a risk factor for H. pylori infection of the child.

CONCLUSIONS

This longitudinal study suggests that infected mothers are the main source of H. pylori infection of their children.

Immune responses to Helicobacter pylori colonization: mechanisms and clinical outcomes

Helicobacter pylori colonizes the stomachs of half of the world's population and usually persists in the gastric mucosa of human hosts for decades or life. Although most H. pylori-positive people are asymptomatic, the presence of H. pylori is associated with increased risk for the development of peptic ulcer disease, gastric adenocarcinoma and gastric lymphoma. The development of a sustained gastric inflammatory and immune response to infection appears to be pivotal for the development of disease. During its long co-existence with humans, H. pylori has evolved complex strategies to maintain a mild inflammation of the gastric epithelium while limiting the extent of immune effector activity. In this review, the nature of the host immune response to H. pylori infection and the mechanism employed by the bacterium to evade them is considered. Understanding the mechanisms of colonization, persistence and virulence factors of the bacterium as well as the innate and adaptive immune responses of the host are critically important for the development of new strategies to prevent the development of H. pylori-induced gastroduodenal disease.

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.

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.

Epidemiology of gastric cancer

The incidence and mortality of gastric cancer have fallen dramatically in US and elsewhere over the past several decades. Nonetheless, gastric cancer remains a major public health issue as the fourth most common cancer and the second leading cause of cancer death worldwide. Demographic trends differ by tumor location and histology. While there has been a marked decline in distal, intestinal type gastric cancers, the incidence of proximal, diffuse type adenocarcinomas of the gastric cardia has been increasing, particularly in the Western countries. Incidence by tumor sub-site also varies widely based on geographic location, race, and socio-economic status. Distal gastric cancer predominates in developing countries, among blacks, and in lower socio-economic groups, whereas proximal tumors are more common in developed countries, among whites, and in higher socio-economic classes. Diverging trends in the incidence of gastric cancer by tumor location suggest that they may represent two diseases with different etiologies. The main risk factors for distal gastric cancer include Helicobacter pylori (H pylori) infection and dietary factors, whereas gastroesophageal reflux disease and obesity play important roles in the development of proximal stomach cancer. The purpose of this review is to examine the epidemiology and risk factors of gastric cancer, and to discuss strategies for primary prevention.

Are endoscopy nurses at risk of infection with Helicobacter pylori from their work?

BACKGROUND

In response to studies suggesting risk of occupational transmission of Helicobacter pylori (HP) to endoscopy staff, this cross-sectional study of seroprevalence to HP in gastroscopy nurses working in West of Scotland hospitals (an area of high endemicity of HP infection) was performed to determine if they were at excess risk relative to peers working in surgical specialities but without gastroscopy exposure. The study aimed to fulfil employer's duties to carry out a suitable risk assessment required by health and safety legislation.

METHOD

This cross-sectional study compares the seroprevalence of HP in gastroscopy nurses and comparators drawn from orthopaedic and trauma units in 10 hospitals during 1998. A directly administered questionnaire collated exposure information on occupational and non-occupational risk factors for infection. Venepuncture was performed for latex agglutination test for IgG to HP. Confounding by socio-economic factors was controlled for by multivariate analysis.

RESULTS

Of the 222 participants, 74 were endoscopy staff (84% response) and 148 (59%) were comparators. Of these, 32.4% of gastroscopy and 33% of comparators were seropositive for HP (OR 0.97, P > 0.9, 95% CI 0.5-1.8). No association was found between gastroscopy exposure variables (frequency, years) or exposure to all endoscopy procedures and HP. Significant associations were found for age, childhood deprivation and greater number of siblings.

CONCLUSION

No excess HP infection was found in gastroscopy nurses. Duties imposed by the health and safety legislation appear discharged by normal infection control procedures. Socio-economic factors are key determinants of HP status.

Trends in the prevalence of Helicobacter pylori in symptomatic children in the era of eradication

PURPOSE

Helicobacter pylori infection is common in Asia and is associated with dyspepsia, peptic ulcer, and gastric cancer. Eradication of the organism remains an important goal. Here, we looked at the trends in the prevalence of H pylori in symptomatic children over an 8-year period to assess the impact of an aggressive eradication program.

METHOD

A retrospective review was carried out between 1997 and 2004. All children with a history of dyspepsia or acute gastrointestinal bleeding were included and underwent gastroscopy. Three antral biopsies were taken during endoscopy and sent for histological analysis. Positivity of H pylori was treated aggressively with quadruple therapy under protocol. The demographic data, the histological findings, and the H pylori status were recorded.

RESULTS

There were a total of 159 patients (71 males, 88 females) who underwent gastroscopy in this period. One hundred nineteen patients showed histological evidence of gastritis, and the positive rate of H pylori was 25.6%. The overall prevalence has not decreased (33.3% in 1997, 27.7% in 2004). Increasing age, however, was associated significantly with the higher risk of H pylori infection.

CONCLUSION

H pylori has a high prevalence in Chinese children with increasing age. Eradication efforts seem to be unsuccessful in the reduction of prevalence. We hypothesize that this may be owing to cross-infection at meal times from sharing chopsticks.

Concordance of Helicobacter pylori infection among children in extended-family homes

Helicobacter pylori is transmitted within households and high concordance is observed among siblings. To better understand the contributions of close interpersonal contact and family relatedness to transmission, we compared concordance of H. pylori infection among 241 sibling and non-sibling children aged 2-18 years in 68, predominantly low-income, Hispanic households with at least two nuclear families. Prevalence of H. pylori infection was 24%. Compared to children with no infected siblings or non-siblings and adjusting for age, odds of H. pylori infection were 1.2 (95% CI 0.52-2.9), 3.2 (95% CI 1.14-9.1), and 9.4 (95% CI 3.1-28.5) for children residing with at least one infected non-sibling, one infected sibling, and with at least one infected sibling and non-sibling, respectively. The study further implicates intersibling transmission as a pathway for H. pylori infection in childhood. In addition, living with a non-sibling in extended-family homes may contribute to infection risk but only in households with prevalent H. pylori infection within all family groups.

Helicobacter pylori-specific immune response in maternal serum, cord blood, and human milk among mothers with and without current Helicobacter pylori infection

We assessed the patterns of Helicobacter pylori (H. pylori) specific maternal antibodies in maternal serum, cord blood, and milk, which might play a role in prevention of H. pylori infection because transferred to the infant. Between November 2000 and November 2001, mothers were recruited after delivery of their offspring. H. pylori infection status was determined by 13C-urea breath test (UBT). Specific H. pylori antibody profiles were analysed using commercial H. pylori-specific enzyme-linked immunosorbent assay and Western blots. Among 898 mothers, 23% had a current H. pylori infection. Median H. pylori IgG antibody titers in serum and cord blood of UBT-positive mothers were 23.8 U/mL and 24.0 U/mL, respectively. Whereas prevalences of H. pylori-specific antibodies in serum of UBT-negative mothers were clearly lower than those among UBT-positive mothers, patterns of H. pylori-specific IgA antibodies in milk were similar among UBT-positive and UBT-negative mothers. Neonates born from H. pylori-infected women are provided with large amounts of transplacentally transferred specific IgG H. pylori antibodies. Breast-fed neonates are additionally provided with specific IgA antibodies in human milk. Notably, the latter may also be activated if exposure of the mother to H. pylori might have been long time ago and been cleared in the meantime.

A Randomized Trial of Triple Therapy for Pediatric Helicobacter pylori Infection and Risk Factors for Treatment Failure in a Population with a High Prevalence of Infection

BACKGROUND

Few trials of treatment for Helicobacter pylori infection have been conducted in high-prevalence or pediatric populations, and risk factors for treatment failure are poorly understood.

METHODS

As part of a study evaluating the effect of H. pylori therapy on iron deficiency, we conducted a household-randomized, open-label treatment trial involving children aged 7-11 years in 10 villages in western Alaska. We screened 690 children, of whom 219 with iron deficiency and H. pylori infection (determined on the basis of positive results of the 13C urea breath test) were enrolled in the treatment phase of the study. These 219 children received treatment with iron sulfate alone (the control group) or with iron sulfate combined with a 2-week course of lansoprazole, clarithromycin, and amoxicillin (the intervention group). Children in the intervention group who were allergic to amoxicillin or macrolides received metronidazole. Children in the intervention group who did not respond to treatment were re-treated with a 2-week course of metronidazole-based quadruple therapy.

RESULTS

Two months after initiating therapy, 34% of 104 children in the intervention group and 0.90% of 111 children in the control group tested negative for H. pylori. Among children in the intervention group, risk factors for treatment failure were lack of metronidazole (adjusted odds ratio [aOR], 145), fewer treatment doses (aOR, 0.74), larger household population (aOR, 1.5), and lower body mass index (aOR, 0.69). These 4 variables predicted most of the variation in H. pylori infection status. Among 50 children who were re-treated, 84% tested negative for H. pylori at the 8-month follow-up visit, including those with poor treatment compliance.

CONCLUSIONS

Among disadvantaged populations with a high prevalence of H. pylori infection, the response to standard treatment regimens may be low. Treatment compliance, household crowding, and re-treatment may influence treatment success. Metronidazole may be appropriate first-line therapy.

The recurrence of Helicobacter pylori infection: incidence and variables influencing it. A critical review

The rate of H. pylori recurrence after eradication of the microorganism seems to be relatively low, at least in developed countries, where the mean annual reinfection rate is of approximately 3% per patient-year of follow-up, although the risk of reinfection in some developing regions is considerably higher. Several findings suggest that recrudescence rather than reinfection is likely to be responsible for most cases of recurrence: (i) the recurrences decrease with time and decline sharply after the first year, and (ii) studies using molecular fingerprinting techniques (polymerase chain reaction [PCR]) confirm that the identified microorganisms (before and after therapy) are usually genetically identical. The lower the efficacy of an antibiotic therapy, the greater the likelihood that recurrence occur, again suggesting that in these cases temporary "clearance" has been achieved rather than true eradication. The value of the (13)C-urea breath test after treatment is higher in those patients who suffer a recurrence; therefore, selection of a lower cut-off value may be helpful to maintain the diagnostic accuracy of posttreatment breath test, and thus preventing recrudescences. The observation of a pattern of histological (active) gastritis without the concomitant finding of H. pylori must raise the suspicion of a diagnostic error. Some studies suggest that recurrence is relatively infrequent, even if the patient's spouse is H. pylori-positive, suggesting that the patient's partner does not act as a reservoir for the reinfection. However, other investigators achieve contrary results, although a common exogenous source of H. pylori (for both partner's infection and patient's reinfection) cannot be ruled out. The oral cavity may be a potential source for recrudescence of gastric infection after successful therapy. When peptic ulcer reappears (sometimes with bleeding recurrence) or gastric MALT (mucosa-associated lymphoid tissue) lymphoma relapses after previous H. pylori eradication, recolonization of the gastric mucosa by the organism has almost always occurred.

The maintenance in the oral cavity of children of tetracycline-resistant bacteria and the genes encoding such resistance

OBJECTIVES

To investigate the maintenance of tetracycline-resistant oral bacteria and the genes encoding tetracycline resistance in these bacteria in children (aged 4--6 years) over a period of 12 months.

METHODS

Plaque and saliva samples were taken from 26 children. Tetracycline-resistant bacteria were isolated and identified. The types of resistance genes and their genetic locations were also determined.

RESULTS

Fifteen out of 18 children harboured tetracycline-resistant (defined as having a MIC>or=8 mg/L) oral bacteria at all three time points. The median percentage of tetracycline-resistant bacteria at 0, 6 and 12 months was 1.37, 1.37 and 0.85%, respectively; these were not significantly different. The MIC(50) of the group was 64 mg/L at all three time points compared with the MIC(90), which was 64 mg/L at 0 months, and 128 mg/L at 6 and 12 months. The most prevalent resistant species were streptococci (68%), which were isolated at all three time points in 13 children. The most prevalent gene encoding tetracycline resistance was tet(M) and this was found in different species at all three time points. For the first time, tet(32) was found in Streptococcus parasanguinis and Eubacterium saburreum. PCR and Southern-blot analysis (on isolates from three of the children) showed that the tet(M) gene was located on a Tn916-like element and could be detected at all three time points, in four different genera, Streptococcus, Granulicatella, Veillonella and Neisseria.

CONCLUSIONS

The results of this study show that tetracycline-resistant bacteria and tet(M) are maintained within the indigenous oral microbiota of children, even though they are unlikely to have been directly exposed to tetracycline.

Seroprevalence of Helicobacter pylori among children in Sana'a, Yemen

BACKGROUND

Helicobacter pylori infection is primarily acquired in early childhood. Its transmission routes are debated. The aims of this study were to determine the seroprevalence of anti-H. pylori immunoglobulin G (IgG) in Yemeni children under 10 years of age, the potential risk factors for contracting H. pylori infection and co-infection of H. pylori with intestinal parasites.

METHODS

Enzyme-labeled immunosorbent assay was used to determine the H. pylori prevalence rate among 572 healthy volunteers aged less than 10 years. Formalin ether concentration methods were used to test the prevalence of intestinal parasites (intestinal roundworms and tapeworms). In addition, we interviewed participants regarding potential risk factors for contracting H. pylori infection.

RESULTS

The seroprevalence of H. pylori antibodies was 9%. The prevalence according to age varied from 0% in children under 2 years to 12.5% in age group 9-10 years. There was a correlation between the amounts of positive antibodies and increasing age. The prevalence rate of H. pylori antibodies was also significantly associated with the practice of drinking water from reused plastic jerry cans, with poor mouth hygiene and with co-infection by intestinal parasites.

CONCLUSION

The prevalence of H. pylori antibodies in Yemen among children under 10 years of age is higher than that reported from other regions for the same age groups. Yemen shares some but not all potential risk factors for H. pylori infection with countries in which similar socioeconomic conditions are found. A possible way of eliminating H. pylori from the population would be via public health measures, i.e. preventing the reuse of plastic jerry cans, and improving sanitation and the standard of living.

The association between Helicobacter pylori infection and adult height

OBJECTIVES

A cross-sectional survey was performed to evaluate the association between H. pylori and adult height.

METHODS

H. pylori infection was assessed using a 13C-urea breath test and height measured by a research nurse using a stadiometer in participants between the ages of 40-49 years.

RESULTS

Height was measured in 2932/3682 participants that attended and were evaluable. H. pylori infected women were 1.4 cm shorter than uninfected women (95% confidence interval, CI = 0.7-2.1 cm) and this statistically significant difference persisted after adjusting for age, ethnicity, childhood and present socio-economic status (H. pylori positives 0.79 cm shorter; 95%CI: 0.05-1.52 cm). H. pylori positive men were 0.7 cm shorter than uninfected men but this did not reach statistical significance (95% CI: -0.1-1.5 cm).

CONCLUSION

Although H. pylori infection is associated with reduced adult height in women, this maybe due to residual confounding.

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.

Helicobacter pylori infection: detection, investigation, and management

Helicobacter pylori infection causes gastritis and peptic ulcers and is associated with the development of gastric cancer. Approximately 50% of the world population is infected with H pylori , with the highest prevalence rates in developing countries. In the vast majority of individuals, infection is acquired during childhood with those of low socioeconomic means and having infected family members being at highest risk for early childhood acquisition. Definitive routes of transmission of the infection are unclear, with evidence suggesting oral-oral, gastric-oral, and fecal-oral routes. If untreated, H pylori infection is lifelong. Although clinical disease typically occurs decades after initial infection acquisition, children infected with H pylori may have gastritis, ulcers, mucosal-associated lymphoid type lymphoma, and, rarely, gastric atrophy with/without intestinal metaplasia (ie, both precursor lesions for gastric cancer). Controversy persists regarding testing for and treating H pylori , if found, in the large number of children who present with recurrent abdominal pain. Because young children (ie, younger than 5 years of age) who are treated and cured of their H pylori infection may be at risk for reinfection, the current recommendations do not recommend treatment unless an ulcer or gastric atrophy is present. However, despite the lack of clinical evidence, the trend is to more aggressively screen children for the presence of H pylori and to treat those children who are found to have the infection. H pylori infection can be eradicated by antimicrobial therapy plus a proton pump inhibitor, but no treatment regimen is 100% effective. Multiple drugs, frequent dosing, and length of treatment often contribute to poor patient compliance, and antibiotic eradication therapy is associated with increasing drug resistance.

Helicobacter pylori status and symptom assessment two years after eradication in pediatric patients from a high prevalence area

OBJECTIVES

To establish the rate of Helicobacter pylori reinfection in children from an H. pylori high prevalence area, possible clinical features predictive of reinfection and the usefulness of re-treatment.

METHODS

65 consecutive children attending the authors' department between 1998 and 2000 who had proven successful H. pylori eradication were enrolled; 52 took part. Patients and family members were invited to undergo C-urea breath testing and to complete a simple questionnaire regarding symptoms and socioeconomic status. Patients with H. pylori reinfection were offered treatment; eradication was assessed by C-urea breath test 8 weeks after completion of treatment.

RESULTS

Of 52 children, 15 (28.8%) were H. pylori positive. Variables predictive of reinfection were age at primary infection and presence of an infected sibling. Although reinfected children were more frequently symptomatic than non-reinfected patients, no specific symptom was associated with reinfection. Of the nine re-treated patients who returned 8 weeks after completing therapy, the bacterium was eradicated in five (56%).

CONCLUSIONS

The 12.8% per year reinfection rate in childhood at 2 years that we observed should prompt a re-evaluation of H. pylori status even after a successful eradication. Living in an H. pylori high prevalence area increases the annual risk of reinfection by approximately fourfold over the annual risk in H. pylori low prevalence areas.

Risk factors for Helicobacter pylori infection in children: an examination of the role played by intrafamilial bed sharing

BACKGROUND

The exact mode of transmission of Helicobacter pylori is yet to be established. Close personal contact among family members appears to be a key factor. The aim of this study was to establish whether sharing a bed or bedroom with an infected family member is an important risk factor for primary childhood H. pylori infection.

METHODS

Fifty-two families with at least 1 child (the index case) with H. pylori infection were recruited. The resultant study population comprised 126 siblings of the index cases. H. pylori infection was established by culture or by histology and urease testing on antral biopsies in index cases and by C-urea breath testing in family members. Data regarding sleeping arrangements within the family were collected.

RESULTS

Sharing a bed or bedroom with an infected sibling at the age of 3 years significantly increased the risk of childhood H. pylori infection [odds ratio, 4.84; 95% confidence intervals, 1.54-15.20; P < 0.01 and 3.68 (1.26-10.75), P = 0.017, respectively]. In addition, a child was at significantly increased risk of being infected if his/her mother or father was H. pylori-positive [odds ratio, 2.52; 95% confidence intervals, 1.03-6.13], P = 0.042 and 2.99 (1.04-8.61), P = 0.042, respectively).

CONCLUSIONS

Sharing a bed or bedroom with an infected sibling in early childhood increases significantly the risk of childhood H. pylori infection. This provides evidence to support horizontal transmission of H. pylori among siblings.

Helicobacter pylori Infection among Patients Visiting a Clinic in Kasama City, Ibaraki Prefecture

We examined Helicobacter pylori infection in patients who visited the Iso Clinic (Kasama City, Ibaraki Prefecture) with abdominal complaints, and determined the prevalence of H. pylori infection by age, sex, endoscopic diagnosis, abdominal complaint, gastric mucosa, and living environment. Peptic ulcer disease was observed in 23.2% of the patients examined with endoscopy, but there was no association between abdominal complaints and the prevalence of H. pylori infection. The prevalence of H. pylori infection was high among patients with peptic ulcer disease and atrophic gastritis. The prevalence of H. pylori infection was higher in the generation born before tae start of the period of rapid economic growth (71.5%) than in the generation born afterward (64.8%). No significant difference was observed between males and females. The prevalence of H. pylori infection was high in those who drank well water during childhood and those who were raised in a house with a nonflushing of toilet (67.2% and 67.5%, respectively). There were no associations with river basin of residence, alcohol consumption, or smoking. The prevalence of H. pylori infection among patients who visited Iso Clinic was higher than that among patients seen at Tama-Nagayama Hospital, Nippon Medical School (Tama City, Tokyo). The difference is attributable to the higher prevalence of H. pylori infection in the elderly.