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

Helicobacter pylori infection in children: relation with current household living conditions

BACKGROUND

Studies demonstrating that deprived household living conditions during childhood are risk factors for acquisition of Helicobacter pylori infection have been performed mainly in adults, who probably acquired the infection several decades ago. This study investigates whether deprived household living conditions remain important risk factors for infection in subjects (children) with recently acquired infection.

AIMS

To examine the relation between current household living conditions and acquisition of H pylori infection in childhood.

SUBJECTS/SETTING

Opportunistically recruited group of 367 children, aged 3 to 15 years, undergoing routine non-gastrointestinal day surgery.

METHODS

Anti-H pylori IgG antibodies measured by a commercial enzyme linked immunosorbent assay validated for use in children. Postal questionnaire collecting sociodemographic data and data on household living conditions.

RESULTS

Infection was associated with social class and overcrowding in the household. After adjustment for age, social class, and household density, a positive association remained between infection with H pylori and bed-sharing between children and parents on one or two nights per week, odds ratio for infection (95% CI), 2.29 (1.21, 4.32) or more frequently, odds ratio for infection (95% CI), 2.95 (1.35, 6.45).

CONCLUSIONS

The continuing importance of household living conditions in the acquisition of H pylori infection is confirmed and household crowding and sharing a bed with a parent are identified as risk factors for infection.

Helicobacter pylori and socioeconomic factors in Russia

BACKGROUND

The factors influencing the acquisition and prevalence of Helicobacter pylori infection remain incompletely understood. In Russia, the demographic and socioeconomic factors are relatively similar, allowing investigation of risk factors that might not be identifiable in a more diverse population.

MATERIALS AND METHODS

Sero-prevalence of H. pylori infection was studied in 520 asymptomatic individuals between the ages of 1 and 75 years, residing in St. Petersburg, Russia. Forty-four children lived in orphanages or communal apartments. Demographic information and socioeconomic factors were evaluated, including educational level, income, and living conditions. Helicobacter pylori status was evaluated by using an enzyme-linked immunosorbent assay for anti-H. pylori IgG.

RESULTS

The prevalence of H. pylori infection was 44% in children and 88% in adults (P < .001). In adults, H. pylori prevalence was independent of socioeconomic factors. The crude and the age-adjusted odds ratios (ORs) in children showed an inverse correlation between the mother's educational level and H. pylori seropositivity [e.g., OR, 1.8; (95% confidence interval (CI) = 1-3.2] for children whose mothers completed only 8 to 10 years of school compared to children whose mothers completed university. Overcrowding in childhood also was associated with increased H. pylori prevalence. Children from orphanages and communal apartments had the highest crowding index and also were at the greatest risk for H. pylori acquisition (age-adjusted OR, 2.1; 95% CI = 1.2-2.5).

CONCLUSIONS

The prevalence of H. pylori infection in Russia correlated with socioeconomic factors, suggesting there are differences sufficient to affect H. pylori transmission. The prevalence of H. pylori infection during childhood forms the basis for the variances in prevalence among populations.

Is Helicobacter pylori transmitted from cats to humans?

BACKGROUND

Subsequent to the isolation of Helicobacter pylori from domestic cats, it has been suggested that the organism might be transmitted from cats to humans. This hypothesis has already gained considerable media attention.

MATERIALS AND METHODS

In a previous study of risk factors for H. pylori infection, 447 factory workers from Stoke on Trent in the UK had provided blood samples for H. pylori serological workup. They had also completed a detailed questionnaire concerning their living conditions, including the possession of any household pets, in childhood. Logistic regression was used to assess the association between cat ownership in childhood and H. pylori seropositivity.

RESULTS

After adjustment for potential confounders, it was found that subjects who had owned a pet as a child were slightly more likely to be H. pylori seropositive than subjects who had not. There was, however, no difference between subjects who had owned a cat and those with other pets.

CONCLUSIONS

These data do not support the hypothesis that H. pylori infection might be transmitted from cats to humans.

Different expression of Helicobacter pylori gastritis in children: evidence for a specific pediatric disease?

BACKGROUND

Infection with Helicobacter pylori causes active chronic gastritis. Once the infection is acquired, gastritis will persist for almost the rest of one's life. To date, very few data are available on H. pylori gastritis in relation to age. Therefore, we attempted to investigate whether H. pylori gastritis in children exhibits features different from H. pylori gastritis in adults of two different age groups.

MATERIALS AND METHODS

Fifty consecutive children with a median age of 11 years (range, 3-18 years) were compared with two groups of 50 adult patients, one group with a median age of 43 (range, 19-56 years) and another group with a median age of 70 years (range, 59-86 years). All patients had H. pylori gastritis unrelated to active peptic ulcer disease. Two biopsy specimens were taken from the antrum and two from the corpus, and the following gastritis parameters were evaluated: degree and activity of gastritis, H, pylori colonization, replacement of foveolar epithelium by regenerative epithelium, mucous depletion, presence of atrophic gastritis with intestinal metaplasia, and presence of lymphoid follicles.

RESULTS

Degree and activity of gastritis, extent of H. pylori colonization, degree of replacement by regenerative epithelium, extent of mucous depletion, degree of atrophic gastritis with intestinal metaplasia, and the presence of lymphoid follicles in the antrum, as well as the presence of lymphoid follicles in the corpus differed significantly (chi-square test: p < .05). All these differences--except the once frequent occurrence of atrophic gastritis with intestinal metaplasia in adults--were attributable to a higher expression of these gastritis parameters in children.

CONCLUSIONS

We conclude that H. pylori gastritis, particularly in the antrum, is more severely expressed in childhood. One reason for this might be a child-specific immune response to an infection with H. pylori. Alternatively, infection may represent a pediatric disease characterized by a nonatrophic, highly expressed form of gastritis, which changes its appearance once the host becomes adapted over time.

Protective immunization against Helicobacter stimulates long-term immunity

Immunization with an oral vaccine composed of whole cell sonicates of Helicobacter felis plus cholera toxin (CT) can protect mice from H. felis challenge. The aim of this study was to determine whether this protective immunity was long-lived. Mice were given the vaccine then left for up to 15 months before challenge. After 15 months, all mice were still protected from H. felis infection, indicating that oral immunization using bacterial antigens plus CT can stimulate long-term local immunological memory.

Prospective relations between Helicobacter pylori infection, coronary heart disease, and stroke in middle aged men

OBJECTIVE

To determine whether Helicobacter pylori, a chronic bacterial infection often acquired in childhood, is associated with increased risk of coronary heart disease and stroke later in life.

DESIGN

Nested case-control study.

SETTING

Prospective study of cardiovascular disease in men aged 40-59 years at entry (1978-1980) in 24 British towns.

SUBJECTS

135 cases of myocardial infarction and 137 cases of stroke occurring before December 1991; 136 controls were identified, frequency matched to cases by town and age group.

METHODS

Serum samples stored at entry were analysed by an enzyme linked immunosorbent assay for the presence of H pylori specific IgG antibodies.

RESULTS

95 of the myocardial infarction cases (70%) and 93 (68%) of the stroke cases were seropositive for H pylori compared with 78 (57%) of the controls (odds ratio for myocardial infarction 1.77, 95% confidence interval (CI) 1.06 to 2.95, P = 0.03; odds ratio for stroke 1.57, 95% CI 0.95 to 2.60, P = 0.07). Helicobacter pylori infection was associated with manual social class, residence in Northern England or Scotland, cigarette smoking, higher systolic pressure and blood glucose, and a lower height-standardised forced expiratory volume in one second. Adjustment for these factors attenuated the relation between H pylori and myocardial infarction (odds ratio = 1.31, 95% CI 0.70 to 2.43, P = 0.40) and effectively abolished the relation with stroke (odds ratio = 0.96, 0.46 to 2.02, P = 0.92). The relation between helicobacter infection and fatal myocardial infarction was slightly stronger (odds ratio 2.41, 95% CI 1.13 to 5.12) but was also markedly attenuated after adjustment (1.56, 95% CI 0.68 to 3.61).

CONCLUSION

In this prospective study the association between Helicobacter pylori infection and increased risk of myocardial infarction and stroke was substantially confounded by the relation between this infection, adult social class, and major cardiovascular risk factors.

Cost effectiveness of screening for and eradication of Helicobacter pylori in management of dyspeptic patients under 45 years of age

OBJECTIVE

To assess the cost effectiveness of screening for and eradicating Helicobacter pylori in patients under 45 years of age presenting with dyspepsia.

DESIGN

A decision analytic model composed of a decision tree to represent the epidemiology of dyspepsia and a Markov process to model the outcomes of treatment.

PATIENTS

Patients under the age of 45 years presenting to their general practitioner with (peptic type) dyspepsia.

INTERVENTIONS

Conventional empirical treatment with healing and maintenance doses of cimetidine v eradication treatment solely in patients with confirmed peptic ulcer; and conventional empirical treatment for all dyspeptic patients compared with the use of a serology test to identify patients with H pylori, who then receive endoscopy to investigate the presence of peptic ulcer disease and, when disease is found, are given eradication treatment with a breath test to confirm successful eradication.

MAIN OUTCOME MEASURES

Expected cumulative costs over a period of 10 years. The proportion of time patients spend without a recurrent ulcer.

RESULTS

After receiving eradication treatment, patients with confirmed ulcer spend an average of 99% of their time free from recurrent ulcer disease compared with 95% after treatment with cimetidine. Eradication treatment costs less than that with cimetidine. When the initial cost of identifying appropriate patients to receive eradication treatment is added to the analysis, however, these cost savings take almost eight years to accrue.

CONCLUSIONS

Enthusiasm for introducing testing for and eradication of H pylori for dyspeptic patients in general practice should be tempered by an awareness that cost savings may take many years to realise.

The prevalence of Helicobacter pylori positivity in asymptomatic children of different ethnic backgrounds living in the same country

OBJECTIVE

To measure the prevalence of Helicobacter pylori seropositivity in a population of apparently healthy children of different ethnic backgrounds, matched for age and socioeconomic background, who were born and continue to reside in the same country.

DESIGN

The presence of Helicobacter pylori specific IgG antibodies was determined during pre-surgery blood analysis in 883 symptom-free children, aged from 1 months to 17 years, who belong to different ethnic populations and were admitted for elective minor surgery. The different groups were matched for age and socioeconomic background.

RESULTS

Seventy-two children (8.2%) had a positive titer for Helicobacter pylori. We observed a significant difference in the prevalence of Helicobacter pylori positivity between symptom-free Caucasian and non-Caucasian children (p < 0.001). However, no difference could be observed between the non-Caucasian groups (p > 0.8).

CONCLUSION

We conclude that significant differences exist in the prevalence of Helicobacter pylori infection between asymptomatic children of different ethnic backgrounds, despite the fact that all investigated subjects were born in Belgium and have been living in this country ever since. Whether this difference is caused by an unknown environmental factor or an, until now, unrecognized genetic predisposition still needs to be evaluated.

Presentation and management of Helicobacter pylori infection in childhood

Helicobacter pylori is responsible for one of the most frequently encountered infectious diseases worldwide. Helicobacter pylori infection can lead to the development of gastritis and peptic ulcer disease. The presence of Helicobacter pylori in the human stomach also represents an increased risk of gastric cancer and gastric lymphoma. Epidemiological data obtained in adults suggest that the actual colonization with Helicobacter pylori is in fact determined by childhood factors. Therefore, the pediatric age group represents the ideal target population for studies concerning the pathogenesis and epidemiology of Helicobacter pylori infection. The present work reflects our experience with regard to the diagnosis, epidemiology and pathogenesis of Helicobacter pylori infection in childhood.

Helicobacter pylori disease in childhood

Helicobacter pylori (H. pylori) is responsible for one of the most frequently encountered infectious diseases worldwide. H. pylori infection can lead to the development of gastritis and peptic ulcer disease. The presence of H. pylori in the human stomach also represents an increased risk for gastric cancer and gastric lymphoma. Epidemiologic data obtained in adults suggest that the actual colonization with H. pylori is in fact determined by childhood factors. Therefore, the pediatric age group represents the ideal target population for studies concerning the pathogenesis and epidemiology of H. pylori infection.

Reflux oesophagitis and Helicobacter pylori infection in elderly patients

Helicobacter pylori is associated with gastritis, peptic ulcers and gastric malignancies. Little attention has been paid to the possibility that it may also have a role in the pathogenesis of reflux oesophagitis. This is especially true in elderly patients who have life-long infection and provide an ideal group to study the mucosal changes associated with the organism. The aim of this study was to determine if H pylori is associated with reflux oesophagitis in elderly patients. Consecutive gastroscopy patients were recruited. Multiple biopsies were taken from oesophagus, stomach, antrum and duodenum for histology and rapid urease tests. Patients also had IgG ELISA antibodies and 13C-urea breath tests performed. Patients with macroscopic or microscopic evidence of reflux oesophagitis were compared to patients with macroscopically normal upper gastrointestinal tracts and no microscopic evidence of reflux. A total of 114 patients were recruited, average age 78.9 years (+/- 5.4). There were 37 refluxers and 33 non-refluxers. We found no evidence for an association between the presence of H pylori and reflux oesophagitis in elderly patients. The high prevalence of H pylori in patients with reflux oesophagitis can be explained by the presence of incidental gastritis.

Cancer in Rwanda

Data are presented on the frequency of malignant tumours registered at the population-based cancer registry in the southern prefecture of Butare, Rwanda, from May 1991 until 2 months before the outbreak of civil war in April 1994. Beginning in 1992, subjects were also interviewed about socio-demographic and life-style factors that have been associated with cancer risk in the West. The distribution of cancer in Rwanda is similar to that in other countries in sub-Saharan Africa. The most frequent cancers are those with possible infectious aetiologies: liver cancer (12%), cervical cancer (12%) and stomach cancer (9%). In addition, cancers known to be associated with HIV infection are relatively frequent (Kaposi's sarcoma [6%] and non-Hodgkin's lymphoma [3%]). Chronic infection, including infection with HIV, high parity and multiple sexual partners are important determinants of cancer incidence in this population. Tobacco consumption is low in Rwanda and there are few tobacco-related tumours, such as lung and laryngeal cancer. Other tumours believed to be associated with aspects of Western life-style, such as colorectal and breast cancer, are also relatively infrequent.

Helicobacter pylori gastritis and serum pepsinogen levels in a healthy population: development of a biomarker strategy for gastric atrophy in high risk groups

This study aimed to estimate the prevalence and type of chronic gastritis in an asymptomatic working population and to determine whether a combination of serum pepsinogen levels and Helicobacter pylori serology could be used to identify a subgroup with atrophic gastritis at elevated risk of gastric carcinoma. A 10% subsample of 544 male volunteer factory workers aged 18-63 years and participating in a larger study underwent endoscopy and biopsy. Of these men, 29 were seropositive for Helicobacter pylori; all but three (89.7%) had chronic gastritis. Serum pepsinogen A levels increased with progression from a corpus predominant pattern of gastritis through pangastritis to an antral predominant pattern. Nine subjects had corpus atrophy, which was in most cases accompanied by fasting hypochlorhydria and hypergastrinaemia. A combination of pepsinogen A below 80 ng ml-1 and Helicobaceter pylori seropositivity detected corpus atrophy with sensitivity 88.9% and specificity 92.3%. A second screening stage, using a pepsinogen A/C ratio of below 2.5 as a cut-off, resulted in a reduction in numbers requiring further investigation but with some loss of sensitivity (77.8%). Application of this two-stage screening programme to the original sample of 544 workers would have resulted in 11 (2.2%) men being selected for follow-up, excluding 25 (5.1%) false negatives. Our results suggest that a combination of serum pepsinogen levels and Helicobacter pylori serology could be useful as a biomarker strategy for detection of individuals at increased risk of gastric carcinoma and for non-invasive investigation of the natural history of Helicobacter pylori gastritis.

Somatisation in children

This review summarises recent work on somatisation in childhood. Minor physiological dysfunction may play a part in a number of cases and associated psychiatric disorders are commonly though not universally found. Contributory family factors include high rates of health problems and of parental psychological distress and there is some evidence for the role of family modelling and reinforcement of illness behaviour. There is suggestive evidence linking somatisation to emotional closeness in families, to family togetherness around health matters and to anomalies in children's social relationships. Somatisation in children can respond to treatments involving cognitive-behavioural and family techniques as well as to sensitive, psychologically sound advice from paediatricians.

Prevalence of Helicobacter pylori infection in asymptomatic children

OBJECTIVE

To determine the prevalence of Helicobacter pylori infection in a sample of asymptomatic Australian children.

METHODOLOGY

A prospective observational study, during a 3 month period, of consecutive children aged 0 to 14 years undergoing minor elective surgical procedures in a Day Surgical Unit at a Melbourne paediatric hospital. Subjects without gastrointestinal symptoms or a family history of peptic ulcers had sociodemographic data recorded and serum collected. Serum anti-H. pylori immunoglobulin G antibodies were measured by an enzyme immunoabsorbent assay previously validated in children from the same population.

RESULTS

H. pylori antibodies were present in 21/147 (14.3%) children aged 3 months to 14 years. Prevalence was not influenced by age or sex, but was greatest in children whose parents migrated from developing nations and lowest in children with Caucasian Australian or Western European parents (25.8 vs 5.9%; P < 0.001). An inverse relationship between social class and infection was also observed (P = 0.02). Multivariate analysis demonstrated the father's ethnic background as the only significant independent risk factor for H. pylori infection (P = 0.002).

CONCLUSIONS

Although seroprevalence of H. pylori appears to be lower in Australian children than in developing countries there are some ethnic groups at substantially greater risk for the acquisition of H. pylori infection and its complications.

Prevalence of Helicobacter pylori in acromegalic patients during treatment with octreotide

BACKGROUND

Octreotide, a synthetic long-acting analogue of somatostatin, now has an established role in the treatment of acromegaly. In acromegalic patients treated with octreotide there is an increased incidence of gallstones and possibly gastritis.

OBJECTIVES

(1) To compare the seroprevalence of Helicobacter pylori (H. pylori) infection, in acromegalic patients treated with octreotide to that in patients given other treatment modalities. (2) To study retrospectively the temporal relation between H. pylori acquisition and octreotide treatment.

PATIENTS

Three groups of acromegalic patients were studied; 35 (20 M) had been treated with octreotide, 17 (10 M) with bromocriptine and 19 (12 M) had received no pharmacological intervention (untreated, surgically treated or treated with radiotherapy).

DESIGN/MEASUREMENTS

The presence of H. pylori infection was assessed serologically (Bio-Rad GAP test for IgG), using stored serum, on the most recent sample from each patient and on serial samples from patients treated with octreotide.

RESULTS

The prevalence of H. pylori seropositivity was similar in each treatment group, 34, 35 and 37%, respectively. Mean age and duration of acromegaly were similar in the first two groups. Patients who had never received medical treatment were slightly younger. GH levels were similar in all three groups. Patients on octreotide who were seropositive for H. pylori did not differ from those with negative serology with respect to age, duration of acromegaly, duration of octreotide treatment or serum GH level. Serial samples in octreotide treated patients showed a change in status in only one patient; 18 patients continued with negative serology during a mean period of 30 (range 4-62) months. In each of the 6 patients with persistently positive serology during octreotide treatment, stored samples predating octreotide therapy were shown to have already been positive.

CONCLUSIONS

The seroprevalence of H. pylori infection in acromegalic patients does not appear to be increased in a manner dependent on the type or duration of medical treatment. In particular, octreotide therapy, while causing the development of histological gastritis in some patients, does not appear to induce the development of H. pylori infection.

Helicobacter pylori infection in Estonian population: is it a health problem?

The role of Helicobacter pylori infection in traditionally noncommunicable diseases as chronic gastritis, peptic ulcer and gastric carcinoma became more evident during the first decade of H. pylori studies. To analyse and evaluate the prevalence of H. pylori infection in Estonia as a population health problem, the data of three randomly selected samples of Estonian population aged over 15 years were used. The infection rate assessments in two representative samples of the population (Kambja 157 persons and Kuressaare 224 persons) were based on H. pylori colonization in the gastric mucosa, and in one sample (Karksi-Nuia 1467 persons) on seroconversion of H. pylori IgG antibodies. The persons studied were divided into groups according to birth cohorts. The population studies in Estonia showed a high prevalence of H. pylori infection among Estonians: 73% in the Kuressaare sample, 78% in the Kambja sample, and 87% in the Karksi-Nuia sample. From the Kuressaare population sample 38 families with 290 persons were included in a family H. pylori infection study and 92.5% of the persons in these families were found to be H. pylori positive. H. pylori infection was frequent in persons who were born at the beginning of this century as well as in those born after World War II up to 30 years ago. It was concluded that H. pylori infection is common in Estonia, both in random persons and their families. It is probable that the infection rate of H. pylori depends to a great extent on the socioeconomic conditions of this country and that acquisition of H. pylori in Estonia starts at an early age.

Helicobacter pylori as a risk factor for cancer

In 1985, gastric cancer was the second most common cause of cancer death in the world. The rapid decline in gastric cancer rates over the last few decades has been attributed to a decline in the prevalence of environmental risk factors for gastric cancer and/or an increase in the prevalence of protective factors. One such risk factor could be the bacterium Helicobacter pylori. Epidemiological studies have shown that areas with high gastric cancer rates often have a correspondingly high prevalence of H. pylori and prospective studies have shown that subjects with serological evidence of H. pylori infection were significantly more likely to go on to develop gastric cancer than those who did not. Helicobacter pylori itself does not appear to be either genotoxic or mutagenic. Infection is, however, associated with increased cell turnover, a chronic immune response accompanied by increased levels of reactive oxygen metabolites and a reduction in gastric levels of ascorbic acid, all conditions that could favour the development of cancer. Nonetheless, the majority of those who are infected with H. pylori do not go on to develop gastric cancer and other factors, such as the strain of the infecting organism or consumption of dietary antioxidants including vitamin C, could also affect the risk of cancer. Finally, it has been estimated that more than one third, and possibly as many as 90% of gastric cancers might be attributable to infection with H. pylori. Prevention and treatment of infection are, therefore, possible approaches to reducing gastric cancer rates. It is, however, unclear what, if any, effect eradication of the infection would have on an individual's risk of gastric cancer and, to date, anti-Helicobacter therapy has only been shown to be of potential benefit in the treatment of low grade gastric MALT lymphomas.

Role of Helicobacter pylori in gastrointestinal disease: implications for primary care of a revolution in management of dyspepsia

The majority of patients with dyspepsia are managed in general practice. However, most of the literature on Helicobacter pylori and its association with gastrointestinal disease has originated from secondary care. This review summarizes the role of H pylori in dyspepsia from the perspective of primary care and suggests a new strategy for the management of dyspeptic patients in this setting. Recent meta-analyses and consensus statements have supported the use of eradication therapy as first-line treatment of peptic ulceration. Studies from primary care have supported the use of eradication therapy in patients who have H pylori related peptic ulcer disease and require long-term H2-antagonist medication, on both clinical benefit and cost-effectiveness grounds. Of the many regimens proposed for the eradication of H pylori, the best evidence supports a triple combination of bismuth, metronidazole and tetracycline. Regimens using proton pump inhibitors may be more acceptable to patients but lack good evidence from trials. Use of a positive serum enzyme-linked immunoabsorbent assay for H pylori antibodies as a criterion for endoscopic investigation has been shown to result in a 23% reduction in endoscopic workload. Further research should answer questions of importance to general practitioners, such as the role of eradication therapy in patients with nonulcer dyspepsia and the effectiveness of eradication of H pylori in the prevention of gastric cancer.

Helicobacter pylori in duodenal and gastric ulcer disease

The decision to treat a patient should in general always be based on potential risk and advantage. Widespread and uncontrolled use of all kinds of anti-H. pylori regimens may promote development of antimicrobial resistant strains. In particular, antimicrobial monotherapy is associated with failure to eradicate H. pylori and induction of resistant strains. Polychemotherapy is much more effective and has a lower risk for development of antimicrobial resistant H. pylori strains but carries the risk of significant drug-related side effects. If the prescribed anti-H. pylori regimen is not effective in at least 80%, or if the patient is not compliant, this type of therapy should not be considered. Also if reinfection is to be expected, the risk may outweigh potential benefits (Graham, 1993). Guidelines published in 1990 by an international working party during the World Congress of Gastroenterology recommended H. pylori eradication only in patients where duodenal ulcer was a serious management problem requiring lifelong maintenance therapy, and in whom complications (bleeding, perforation) had occurred or surgery was considered (Tytgat et al, 1990). Recently less stringent guidelines were recommended. A National Institutes of Health (NIH) Consensus Development Conference has recommended that all patients with gastric or duodenal ulcer who are H. pylori infected should be treated with antimicrobials including patients presenting with an ulcer for the first time. In addition, patients on maintenance antisecretory medication should also be contacted and treated for H. pylori infection (Anonymous, 1994). The ulcer relapse rate during prolonged follow-up after H. pylori eradication is very low. Despite this, it is advised that antisecretory medication is continued after successful H. pylori eradication in patients with previous ulcer complications. In all other patients maintenance antisecretory medication can be stopped after successful eradication. It is not known whether H. pylori eradication lowers the risk of NSAID-induced ulceration or whether the risk of ulcer complications is reduced.

Age dependent hypergastrinaemia in children with Helicobacter pylori gastritis--evidence of early acquisition of infection

Acute Helicobacter pylori associated gastritis causes achlorhydria, a powerful stimulus to gastrin secretion. If H pylori infection is acquired primarily in early childhood, then the degree of hypergastrinaemia in seropositive children should be age dependent. Anti-Helicobacter antibodies and fasting gastrin concentrations were measured in 439 children aged 4 to 13 years attending hospital for routine day case surgery not connected with any gastrointestinal disorder. Thirty per cent were seropositive for H pylori. There was an inverse relationship between the fasting gastrin concentration and age; the mean fasting gastrin in children aged 4-5 years, 155 ng/l, was significantly higher than that seen in children aged 12-13 years, 90 ng/l. The more noticeable hypergastrinaemia seen in young children with H pylori associated gastritis may reflect achlorhydria associated with acute H pylori infection and suggests that this is primarily acquired in early childhood.

A population based study of Helicobacter pylori infection in a European country: the San Marino Study. Relations with gastrointestinal diseases

Helicobacter pylori is present worldwide but few large population studies exist on the epidemiology of the infection. A random cross sectional study was performed of H pylori infection in the adult population of San Marino, a European country with high gastric cancer rate, to assess its prevalence and to evaluate its relations with gastrointestinal disease. In 2237 subjects (77% of the initial sample) H pylori IgG antibodies were detected with enzyme linked immunosorbent assay (ELISA) and immunoblotting. A questionnaire including questions about occupation, place of birth, and smoking was given to all subjects. Dyspepsia, peptic ulcer, and gastric cancer in the subjects, relatives, and partners as well as use of drug, dental treatment/prostheses, and gastrointestinal endoscopies, were evaluated by multivariate analysis. H pylori prevalence was of 51%, increased with age from 23% (20-29 years) to 68% (> or = 70 years), and was higher among manual workers. H pylori was independently associated with ulcer (OR = 1.63, 95% confidence intervals (CI) = 1.16 to 2.27), H2 antagonists (OR = 1.94, 95% CI = 1.21 to 3.10), and benzodiazepines (OR = 1.57, 95% CI = 1.02 to 2.42), dental prostheses (OR = 1.25, 95% CI = 1.05 to 1.49), gastroscopy in the past five years (OR = 1.50, 95% CI = 1.05 to 2.14), peptic ulcer in siblings (OR = 1.52, 95% CI = 1.09 to 2.12), gastric cancer in father (OR = 1.61, 95% CI = 1.02 to 2.52). The association of seropositivity with history of ulcer, gastric cancer in family, gastroscopy, and H2 antagonists suggests that H pylori is an epidemiological key factor in the pathogenesis of gastroduodenal diseases in this area.

Helicobacter pylori infection in childhood: risk factors and effect on growth

OBJECTIVE

To investigate the current prevalence of Helicobacter pylori infection in childhood, the risk factors for infection, and the effect of infection on growth in preadolescent schoolchildren.

DESIGN

Population based sample of 7 year old schoolchildren followed up at age 11; data on risk factors for infection collected at age 7; presence of infection at age 11 determined by measurement of salivary IgG against H pylori by a newly developed enzyme linked immunosorbent assay (ELISA). Height was measured at 7 and 11 years of age.

SUBJECTS

554 schoolchildren from Edinburgh.

RESULTS

62 (11%) children had H pylori infection. Independent risk factors for infection were single parent families (adjusted odds ratio = 2.5; 95% confidence interval 1.1 to 5.7), the 10% most crowded homes (3.1; 1.3 to 7.2), and schools serving predominantly rented housing estates (2.5; 1.0 to 6.5). School catchment area was more important than parental social class or housing tenure. Growth in height between 7 and 11 was diminished in infected children by a mean of 1.1 cm (0.3 to 2.0 cm) over four years. This growth reduction was largely confined to girls (1.6 cm over four years), among whom it correlated with salivary IgG (P = 0.015).

CONCLUSION

Data from salivary assay to investigate the epidemiology of H pylori suggest that factors relating to the type of community in which the child lives may now be as important for acquisition of this infection as features of the family home. The greater reduction of growth among infected girls raises the possibility that H pylori infection may delay or diminish the pubertal growth spurt.