A 2-year study of Helicobacter pylori in children

Factors for Negative Result in Serum Anti-Helicobacter pylori IgG Antibody Test in Adult Subjects With Nodular Gastritis: A Single-center Study

Aim: Nodular gastritis has been demonstrated to be strongly associated with Helicobacter pylori infection. The present retrospective study was performed to elucidate factors related to a negative serum antibody test result in adults with nodular gastritis.

Materials and methods: We investigated 116 H. pylori-positive subjects endoscopically diagnosed with nodular gastritis and subjected to a serum anti-H. pylori immunoglobulin G (IgG) antibody test. The degree of gastric mucosal atrophy and the presence of spotty redness in the gastric body and fornix were carefully determined by observations of endoscopic images.

Results: Of the 116 investigated subjects, 108 were positive and 8 negative in serum anti-H. pylori IgG antibody test results. The degree of gastric mucosal atrophy was mild in seven among eight seronegative cases. The levels of pepsinogen II in serum in patients with negative antibody test findings were significantly lower as compared to those found positive, while the pepsinogen I/II ratio tended to be higher in subjects shown negative by the test. Only 1 of 69 with spotty redness was negative in serum anti-H. pylori IgG antibody testing, while 7 of 47 without spotty redness were negative. Multiple logistic regression analysis of subjects with a negative test result revealed that the absence of spotty redness shown by endoscopy was a significant risk factor.

Conclusion: The absence of spotty redness, which may reflect the degree of gastric body inflammation, is a significant factor indicating increased risk for a negative serum anti-H. pylori IgG antibody test result in subjects with nodular gastritis.

Association between infection and delayed growth in children: A meta-analysis

Helicobacter pylori (H. pylori) infection is associated with extra-gastrointestinal diseases in children. The present study aimed to investigate the potential association between H. pylori infection and growth in children. The PubMed, Exerpta Medica dataBASE, Cochrane Library and Chinese Biomedical Literature Database databases were comprehensively searched for relevant publications dated between January 1st 1994 and January 1st 2019. Delayed childhood growth was defined according to the age-appropriate criteria in the World Health Organization Child Growth Charts (2006 edition). The odds ratios (ORs) and 95% CIs were pooled using the fixed-effects model and subgroup and sensitivity analyses were performed using Review Manager (version 5.3; Cochrane) and STATA (version 12.0; StataCorp LP) software. A total of 15 observational studies comprising 4,199 subjects were included in the present study. A higher frequency of delayed growth was observed in H. pylori-positive children compared with that in H. pylori-negative children (OR, 1.51; 95% CI, 1.28-1.78), particularly for linear growth (OR, 1.63; 95% CI, 1.32-2.00). The aforementioned association was only observed when H. pylori infection was detected using ¹³C-urea breath tests (OR, 1.72; 95% CI, 1.22-2.40) or serum IgG antibodies targeted against H. pylori (OR, 1.81; 95% CI, 1.35-2.44). H. pylori infection was also associated with delayed childhood growth in studies with a H. pylori prevalence of ≤30% (OR, 1.71; 95% CI, 1.31-2.23) or >30% but not >50% (OR, 1.43; 95% CI, 1.10-1.86). The association between infection and growth was only statistically significant in the cross-sectional (OR, 1.43; 95% CI, 1.18-1.73) and case-control (OR, 1.81; 95% CI, 1.23-2.67) studies. No significant heterogeneity among studies was identified in the present analysis. According to Begg's and Egger's linear regression methods for funnel plots and quantification assessments, no publication bias was identified. The trim and fill method further suggested that H. pylori-positive children were prone to delayed linear growth. Therefore, the present study suggested that preventing and detecting H. pylori infection in children may be critical to ensure normal growth and development during childhood.

Contribution of genetic amplification by PCR for the diagnosis of Helicobacter pylori infection in patients receiving proton pump inhibitors

Background

Helicobacter pylori detection by standard methods may be altered by proton pump inhibitor (PPI) use. However, some patients cannot or should not interrupt PPI use before undergoing testing for H. pylori. Polymerase chain reaction (PCR) could allow more reliable H. pylori detection even in patients taking PPIs.

Objective

The aim of our study is to compare the H. pylori infection diagnostic value of histological examination without and with immunohistochemical staining, bacterial culture and PCR, in PPI-treated vs untreated patients.

Methods

Patients undergoing a gastric endoscopy for upper digestive symptoms were included. Gastric biopsy samples were obtained. The impact of taking PPI on the diagnostic performance of the different methods was studied. PCR results were confirmed by sequencing the glmM gene.

Results

A total of 497 patients were included, of whom 192 were H. pylori positive. Fifty-two patients received PPIs during the 14 days preceding the endoscopy while 140 did not. All methods had lower sensitivity than PCR, in all cases (PPI treatment or not). PPI use did not change significantly the methods' sensitivities.

Conclusion

The PCR method showed the best performance for the detection of H. pylori in gastric samples, whether or not patients received previous PPI treatment. This diagnosis test could become a new gold-standard test, especially in patients undergoing PPI treatment.

Association of the Helicobacter pylori cagA, vacA, and iceA genotypes with chronic follicular gastritis in a Colombian population at high risk for gastric cancer

INTRODUCTION AND OBJECTIVE

Follicular gastritis is associated with Helicobacter pylori infection, but little is known of its relation to bacterial genotypes. Our aim was to establish the relation between follicular gastritis and different H. pylori strains.

MATERIALS AND METHODS

An analytic case-control study was conducted that included 36 patients with follicular gastritis (cases) and 83 with nonatrophic gastritis (controls). The sociodemographic information was obtained through a questionnaire. Biopsies were evaluated according to the Sydney System and the Wotherspoon scoring system. Helicobacter pylori genotyping was performed using the polymerase chain reaction technique. The quantitative variables were presented as mean and standard deviation and the qualitative variables as proportions and absolute frequency. The effect of each variable on outcome (follicular gastritis) was evaluated through the odds ratio and its 95% confidence interval. Statistical significance was set at a P<0.05.

RESULTS

Follicular gastritis was associated with Helicobacter pylori infection (OR: 13.41, CI: 1.7-103, P=0.01). The CagA+ genotype was present in 56.5% of the cases and 58% of the controls. The cytotoxic VacAs1m1strain was present in 82% of the isolates in both groups. IceA1 frequency was 34.8% in the cases and 26% in the controls and the difference was not statistically significant.

CONCLUSIONS

The population studied had elevated frequencies of cytotoxic Helicobacter pylori strains and the iceA1 genotype was more frequent in follicular gastritis.

Helicobacter pylori Infection and Children's Growth: An Overview

OBJECTIVES

Helicobacter pylori infection is acquired in early childhood, yet its role in children's health is still not fully clear. In this narrative review, we focused on the association between H pylori infection and children's growth.

METHODS

A literature search of the Ovid MEDLINE (till June 2015) and EMBASE (till August 2015) databases was performed using the terms "Helicobacter pylori, growth, body height, growth disorders and child development." Original studies that addressed the association between H pylori infection or eradication and children's growth were reviewed and the risk of bias of each study was assessed.

RESULTS

The existing evidence is based on observational studies (N = 48) and suggests that H pylori infection may adversely influence children's growth; findings were more consistent across studies with low risk of bias. Regarding linear growth, observational studies have repeatedly linked between H pylori infection and slower or diminished linear growth; yet, it is not known whether this association is causal. The association between H pylori infection and ponderal growth has been less consistent. Scarce evidence exists on the effect of H pylori eradication on children's skeletal growth and weight gain, but there is an indication that H pylori eradication may benefit nutritional status.

CONCLUSIONS

H pylori infection may impair children's growth. Additional studies, especially clinical trials, are needed to elucidate the role of H pylori eradication in children's growth, and the mechanisms that may be involved in such.

Infection and inflammation in somatic maintenance, growth and longevity

All organisms must display a certain degree of environmental adaptability to survive and reproduce. Growth and reproduction are metabolically expensive and carry other costs that contribute to aging. Therefore, animals have developed physiologic strategies to assess the harshness of the environment before devoting resources to reproduction. Presumably, these strategies maximize the possibility for offspring survival. Current views of aging reflect a trade-off between reproductive fitness and somatic maintenance whereby environmental stress induces an adaptive metabolic response aimed at preserving cellular integrity while inhibiting growth, whereas favorable environmental conditions (abundance of food and water, and optimal temperature, etc.) promote growth and reproductive maturity but simultaneously increase cellular damage and aging. Here we propose that the prevalence of infectious pathogens in a given niche represents an additional environmental factor that, via innate immune pathways, actively shifts this balance in favor of somatic maintenance at the expense of reproduction and growth. We additionally propose the construction of a genetic model system with which to test this hypothesis.

Frequency of Helicobacter pylori infection among Egyptian children presenting with gastrointestinal manifestations

BACKGROUND AND AIMS

Recurrent abdominal pain (RAP) and other gastrointestinal (GI) symptoms are common complaints among children. The role of Helicobacter pylori in the causation of these complaints remains controversial. The aim of this study was to determine the frequency of H. pylori infection among children presenting with GI manifestations and to determine the most common clinical presentation of the infection in Egyptian children.

PATIENTS AND METHODS

This prospective cross-sectional study included 150 consecutive patients aged 5-15 years who presented to the outpatient clinic of Cairo University's Specialized Pediatric Hospital with GI complaints. Screening for H. pylori infection was performed using a 13C-urea breath test (13C-UBT), and in patients whose 13C-UBT was positive, diagnosis was confirmed by visualizing the bacterium in biopsy specimens obtained by GI endoscopy.

RESULTS

RAP was the most frequent GI complaint of the study population (82%), followed by anorexia (6.7%), vomiting (6.7%), and chronic diarrhea (4.7%). Seventy percent of these patients were positive for the 13C-UBT. Ninety-one of the patients who complained of RAP had a positive 13C-UBT, whereas the remaining 32 patients who had RAP had a negative 13C-UBT, a difference that was statistically significant (P=0.023). However, no statistically significant differences were found between the 13C-UBT result among patients with anorexia, vomiting, or diarrhea (P=0.153, 1.00, and 0.447, respectively).

CONCLUSION AND RECOMMENDATIONS

Screening for H. pylori infection should be performed for school-aged children who have GI complaints, especially for those who complain of RAP.

High level of antimicrobial resistance in French Helicobacter pylori isolates

BACKGROUND

Helicobacter pylori is a human pathogen responsible for serious diseases including peptic ulcer disease and gastric cancer. The recommended triple therapy included clarithromycin but increasing resistance has undermined its effectiveness. It is therefore important to be aware of the local prevalence of antimicrobial resistance to adjust treatment strategy.

MATERIALS AND METHODS

Overall, 530 biopsies were collected between 2004 and 2007. The antimicrobial susceptibility of H. pylori was determined by E-test and molecular methods.

RESULTS

Among these, 138/530 (26%) strains were resistant to clarithromycin, 324/530 (61%) to metronidazole and 70/530 (13.2%) to ciprofloxacin. Whereas no resistance against amoxicillin and tetracycline was observed, only one strain was resistant to rifampicin. Compared to the patients never treated for H. pylori infection, the prevalence of resistance was significantly higher in patients previously treated (19.1% vs 68% for clarithromycin; 13.2% vs 53.3% for both clarithromycin and metronidazole). The trend analysis revealed an increase of primary resistance to ciprofloxacin between 2004 and 2005 (7.3%) vs 2006-2007 (14.1%) (p = .04) and the secondary resistance reached 22.7% in 2007. Interestingly, 27 biopsies (19.6%) contained a double population of clarithromycin-susceptible and -resistant strains.

CONCLUSIONS

The reported high prevalence of clarithromycin and multiple resistances of H. pylori suggest that the empiric therapy with clarithromycin should be abandoned as no longer pretreatment susceptibility testing has assessed the susceptibility of the strain. As culture and antibiogram are not routinely performable in most clinical laboratories, the use of molecular test should be developed to allow a wide availability of pretreatment susceptibility testing.

Seroprevalence of Helicobacter pylori among Tunisian blood donors (outpatients), symptomatic patients and control subjects

OBJECTIVES

Helicobacter pylori is a worldwide infection, although little data are available in the Tunisian population. The aims of our study were to detect the prevalence of H. pylori in a blood-donor population (n=250) and in another population of hospital-consulting patients comprising 87 symptomatic patients and 59 controls, and to determine the factors that influence the prevalence.

MATERIALS AND METHODS

Study subjects answered a standardized questionnaire, and IgG anti-H. pylori and anti-cag were detected by ELISA. In the second population, culture and cagA polymerase chain reaction were performed.

RESULTS

The seroprevalence of H. pylori in blood donors was 64%, and 11% had anti-cag. All patients positive for anti-cag were also positive for anti-H. pylori antibodies. The seroprevalence of H. pylori was 99.3% in the hospital-consulting patients, of whom 55.5% were positive for anti-cag. The difference between the anti-cag and symptomatic patients (66.7%) and controls (39%) was significant. Symptomatic patients had a higher rate of anti-cag (66.7%) compared with the controls (39%) and blood donors (11%).

CONCLUSION

H. pylori seroprevalence in blood donors is low (64%) compared with symptomatic patients (99.3%), and anti-cag was statistically associated with symptomatic patients and pathology. Also, some environmental factors were correlated with H. pylori seroprevalence.

Positive association between Helicobacter pylori and gastroesophageal reflux disease in children

OBJECTIVES

The role of Helicobacter pylori (H pylori) in gastroesophageal reflux disease (GERD) remains controversial, particularly in children, because there are limited published data. Adult studies suggested that H pylori infection may protect against GERD by causing atrophic gastritis, which leads to reduced gastric acid secretion. The objective of our study was to determine the role of H pylori infection in the development of GERD in a pediatric population.

PATIENTS AND METHODS

A retrospective analysis of 420 patients (M:F = 214:206) who underwent esophagogastroduodenoscopy (EGD) with biopsies between January 2000 and April 2006 was conducted. Patient demographics, clinical indications for EGD and the prevalence of reflux esophagitis (RE), the biomarker for GERD, in 2 groups, H pylori positive and H pylori negative, were reviewed. The prevalence of RE in the H pylori-positive and H pylori-negative groups was further analyzed on the basis of sex and age (<1 year, 1-10 years, >10 years). The mean age of the study population was 8.2 years (range 0-20 years). The clinical indications for EGD were as follows: recurrent abdominal pain (n = 186, 44%), malabsorption (n = 80, 19%), persistent vomiting (n = 80, 19%), suspected eosinophilic gastrointestinal disorders (n = 63, 15%), and others such as upper gastrointestinal bleeding or inflammatory bowel disease surveillance (n = 11, 3%). Statistical analysis was performed by using chi test, Fisher exact test, and multivariate logistical regression analysis.

RESULTS

Among the 420 patients, 16 patients (3.8%) were positive for H pylori and 167 patients (39.8%) were found to have RE. Thirteen patients with H pylori were found to have histologic evidence of RE. The prevalence of RE in the H pylori-positive population was 81.3% compared with 38.1% in the H pylori-negative population (P < or = 0.05). There were no patients with H pylori in the youngest age group. In the second age group (1-10 years), 100% of the H pylori-positive patients had RE, whereas 44.6% of the H pylori-negative patients had RE (P < or = 0.05). Both male and female patients with H pylori had a higher prevalence of RE, 77.8% and 85.7%, respectively. On a multivariate logistical regression, for the overall study cohort, H pylori-positive patients had an odds ratio of 5.79 of developing RE compared with H pylori-negative patients (P < or = 0.05).

CONCLUSIONS

Our study results indicate that there is a significantly higher prevalence of RE in an H pylori-infected cohort independent of age or sex. The findings suggest that H pylori infection in children is positively associated with RE.

Severe iron-deficiency anaemia in adolescents: consider Helicobacter pylori infection

AIM

This article describes the association of severe iron-deficiency anaemia with Helicobacter pylori gastritis.

RESULTS

We report three children who had symptomatic iron-deficiency anaemia with no obvious clinical cause and refractory to iron replacement therapy. All three underwent a diagnostic endoscopy and were found to have H. pylori gastritis. Histopathology confirmed inflammatory changes consisting of dense bands of clusters of plasma cells within the lamina propria and two of the three adolescents were noted to have numerous H. pylori in gastric crypts and glands. Two of the three cases had a urease positive test. Iron deficiency was successfully corrected following antibiotic eradication of H. pylori infection.

CONCLUSIONS

This case series highlights the importance of considering H. pylori infection as a cause of refractory iron-deficiency anaemia in adolescents, even in the absence of gastrointestinal symptoms.

[Helicobacter pylori infection in children]

Knowledge about Helicobacter pylori infection in children continues to advance. While its prevalence appears to be falling in developed countries, it remains a major problem in developing nations. Its transmission pathway remains highly controversial. It has not yet been definitively elucidated, although the oral-oral route seems most probable. Infection is most often intrafamilial. Risk factors for infection are associated with low socioeconomic level, including overcrowding, unhygienic conditions, sharing beds in childhood, low maternal educational level. Infection in children differs from that in adults in three respects: symptoms, endoscopic appearance of the gastric mucosa, and histologic appearance of lesions. No study has established a clear association between recurrent abdominal pain and H. pylori infection. Nonetheless, in proven infections, recurrent abdominal pain is the most common marker. More recently, an association has been reported between H. pylori infection and iron deficiency anemia. The endoscopic aspect most suggestive of H. pylori infection in children is micronodular gastritis, but it is not specific to H. pylori infection. In children as in adults, H. pylori infection is always associated with histologic gastritis. Many questions about H. pylori remain unanswered, and numerous studies are still needed.

Helicobacter pylori primary resistant strains over 11 years in French children

The yearly prevalence between 1994 and 2005 of primary resistance to amoxicillin, metronidazole, and clarithromycin of 377 Helicobacter pylori strains isolated from children was studied. All the H. pylori strains were susceptible to amoxicillin, 138/377 (36.7%) were resistant to metronidazole, 86/377 (22.8%) to clarithromycin, and 30/377 (7.9%) to both metronidazole and clarithromycin. Over the entire period, resistance to clarithromycin did not change, whereas metronidazole resistance decreased significantly from 43.3% (1994-1998) to 32% (1999-2005), P = 0.001.

The association between Helicobacter pylori infection and height in children from an urban community in north-east Brazil

BACKGROUND

An association between Helicobacter pylori infection and short stature in children has been described recently.

AIM

To describe differences in stature between H. pylori-infected and non-infected children in a low-income community in north-east Brazil.

METHODS

H. pylori status was evaluated by 13C-urea-breath test; centile values for weight and height were calculated for each child.

RESULTS

The prevalence of H. pyloni was 55.8% (197/353) and increased with age. Of 197 H. pylori-positive children, 62% were below the 25th centile for height compared with 48% of H. pylori-negative children (75/156) [AOR (adjusted odds ratio) 1.61, 95% CI 1.04-2.49, p=0.03] after adjustment for variables with p < 0.25 in univariate analysis (gender, number of residents, of children per household and of persons per bed). These results were significant only when older children were included. Thus, in children aged 8-14 years, 80% (89/111) of H. pylori-positive were <25th centile for height compared with 63% (35/56) of H. pylori-negative children (p=0.01). Compared with children with a height >25th centile, the AOR for H. pylori infection increased from 2.42 in the crude analysis to 6.62 after adjustment (p=0.006).

CONCLUSIONS

H. pylori is associated with short stature in older children living in a poor urban community in Brazil.

The relationship of Helicobacter pylori positivity with age, sex, and ABO/Rhesus blood groups in patients with gastrointestinal complaints in Turkey

BACKGROUND

To determine the magnitude of Helicobacter pylori infection in patients with gastrointestinal complaints in Turkey.

METHODS

We studied 1680 patients with variable gastrointestinal complaints. The H. pylori infection status was determined using C-14 urea breath test (UBT). Overall, 1567 patients (548 male, 1019 female; age range 4-80 years, mean 29.37 +/- 17.30 years) were included in this study. The relationship between H. pylori positivity and age, sex, sociodemographic characteristic, blood groups, and gastrointestinal diagnosis was determined.

RESULTS

H. pylori positivity was found to be 68%. The difference in positivity rates between age groups 4-9 years and other groups was statistically significant (p = .001). H. pylori positivity was 67.7% in males and 68.2% in females (p = .865). H. pylori positivity was 72.1, 65.1, 70, and 68.4% in blood groups A, B, AB, and O (p = .703), and 68.9% and 76.3% in Rh (+) and Rh (-) blood subgroups, respectively (p = .292). There was no statistically significant difference between H. pylori positivity and gastrointestinal diagnosis (p = .980). There was significant association between increased number of household members and low socioeconomic status, and H. pylori positivity (p < .001). Living in rural and suburban area was significantly associated with H. pylori positivity compared with living in urban.

CONCLUSIONS

H. pylori infection positivity rate was 68% in symptomatic subjects in Turkey and the positivity rate was significantly lower at age 4-9 years than the other age groups. It was not related to gender, ABO, and Rh blood groups and gastrointestinal diagnosis. Low socioeconomic conditions and living in rural and suburban area were significantly associated with H. pylori positivity.

Clarithromycin resistance in Helicobacter pylori strains isolated from French children: prevalence of the different mutations and coexistence of clones harboring two different mutations in the same biopsy

BACKGROUND

The aim of our study was to assess the different mutations involved in clarithromycin-resistant Helicobacter pylori strains isolated from French children and their temporal trends.

METHODS

The point mutations of H. pylori were detected by PCR followed by RFLP technique in 50 clarithromycin-resistant strains collected between 1993 and 2004 in France.

RESULTS

Clarithromycin resistance was observed in 23% (50/217) of H. pylori isolates. Two mutations A2143G and A2142G in the 23S rRNA genes of H. pylori were detected. The former was found in 45/50 (90%) of isolates. The rate of resistance increased with time from 18.6% in the period 1993-1996 to 41.6% in 2001-2004. No significant difference was observed in the distribution of mutations during the same periods. No correlation was found between any mutation and age, sex, and ethnic origin of children. Furthermore, no significant differences in minimal inhibitory concentrations level were observed according to the different point mutations. In all cases, only one point mutation was present, except in two cases where two different mutations were found in two different clones from the same biopsy.

CONCLUSION

The mutation A2143G is predominant in clarithromycin-resistant H. pylori strains isolated from children in France. We report for the first time the presence of two clarithromycin-resistant clones harboring two different mutations of the 23S rRNA genes present in the same biopsy specimen and genotypically identical as demonstrated by RAPD fingerprinting.

Serum ferritin, vitamin B(12), folate, and zinc levels in children infected with Helicobacter pylori

We sought to explore the relationship between Helicobacter pylori infection and serum ferritin, vitamin B(12), folate, and zinc status among children. Fifty patients aged 5-18 years who underwent upper gastrointestinal endoscopy because of dyspeptic symptoms, were studied, prospectively. Patients were grouped as H. pylori positive (group 1, n=32) or H. pylori negative (group 2, n=18) by histopathologic examination and rapid urease test. Fasting serum ferritin, vitamin B(12), folate, and zinc levels of patients were measured. Both groups were indifferent according to age, gender, height standard deviation score (H(SDS)), and weight standard deviation score (W(SDS)). Serum ferritin levels were 33+/-26 and 50+/-46 ng/mL (P=.098), vitamin B(12) levels were 303+/-135 and 393+/-166 pg/mL (P=.042), folate levels were 9.64+/-3.2 and 9.61+/-2.8 ng/mL (P=.979), and zinc levels were 95+/-48 and 87+/-31 mug/dL (P=.538), in groups 1 and 2, respectively. Ferritin levels of 14 (43.8%) patients in group 1 and 6 (33.3%) patients in group 2 were below the normal range (P=.470). Serum vitamin B(12) levels of 9 children (28%) in group 1 and 2 children (11%) in group 2 were below the normal range (P=.287). The findings of the present study suggest that H. pylori infection has a negative effect on serum ferritin and vitamin B(12) levels in children. This negative effect on vitamin B(12) levels is rather marked in contrast to that on ferritin levels. H. pylori infection has no significant effect on serum folate or zinc levels among children.

A prospective study for the association of Helicobacter pylori infection to a multidimensional measure for recurrent abdominal pain in children

BACKGROUND

There is a controversial association between Helicobacter pylori infection and recurrent abdominal pain (RAP) in childhood and inconsistent information on specific symptomatology of the infection.

AIMS

To examine the prevalence of H. pylori infection among children with RAP compared to asymptomatic children.

METHODS

Two prospective studies were conducted. The first study enrolled 223 children diagnosed with RAP from two pediatric gastroenterology clinics in Houston, Texas. Children were qualified if they were identified by their physician as having RAP. A new multidimensional measure for RAP (MM-RAP) consisting of four scales (pain intensity scale, symptoms scale, disability scale, and satisfaction scale) was administered to each child/parent. The second study enrolled 330 asymptomatic children from the same community who did not have any upper gastrointestinal symptoms. Symptomatic and asymptomatic children underwent (13)C-urea breath testing.

RESULTS

In the first study, the prevalence of H. pylori in children with RAP was 11% and fell with age from 20% at age < or = 5 years to 7% for children > 10 years (OR = 2.7, 95% CI = 0.7-11.2). There was no association between the mother's educational level and H. pylori prevalence; (12% among children whose mothers completed college versus 11% among those who had elementary school, p = .8). No relationship was found between H. pylori and mean scores of the RAP scales. In the second study, the prevalence of H. pylori in asymptomatic children was 17% and increased with age from 11% for children < or = 5 years to 40% for children > 10 years (OR = 5.4, 95% CI = 2.0-13.8). The mother's educational level was inversely correlated with H. pylori (OR = 3.0, 95% CI = 2.2-6.1, p < .01).

CONCLUSIONS

The epidemiologic patterns of H. pylori infection differed significantly between symptomatic and asymptomatic children. Younger children suffering from RAP are more likely to be infected with H. pylori than older children with the same complaint, suggesting that early acquisition may manifest in symptoms that lead to clinic visits.

[Helicobacter pylori infection in the child population in Spain: prevalence, related factors and influence on growth]

INTRODUCTION

A causal relationship between Helicobacter pylori infection and the occurrence of digestive diseases in adults and children has been proven. Worldwide, the prevalence of H. pylori varies and it is possibly influenced by differences in the level of development. The goals of this study were a) to ascertain the prevalence of H. pylori infection in the child population in Spain, b) to study several factors related to this infection, and c) to establish its possible influence on growth.

PATIENTS AND METHODS

We performed a descriptive, cross-sectional survey of a representative sample of children aged 1 to 14 years old. The sample consisted of 284 children (prevalence 5 15 %; accuracy 5 4 %; CI > 95 %), selected at random and stratified by age and sex. A pre-coded questionnaire was used for data collection. Diagnosis of H. pylori was established by detection of H. pylori antigen in stools with enzyme immunoassay.

RESULTS

The sample consisted of 144 boys and 140 girls, with a mean age of 6.89 6 4.25 years. The prevalence of H. pylori infection was 15.8 % and progressively increased with age: 1- to 3-year-olds (8.4 %), 4- to 9-year-olds (13.9 %), 10- to 14-year-olds (24 %) (p < 0.05). The prevalence was significantly higher in boys (p < 0.01). Analysis of socio-environmental variables showed a higher H. pylori infection rate in children from families with a low socioeconomic level (p < 0.01), a high rate of overcrowding (p < 0.05), and in immigrants (p < 0.001). The H. pylori infection rate was higher in children with recurrent abdominal pain (p < 0.001) and in those whose parents had suffered from gastroduodenal disease (p < 0.001). H. pylori infection was more frequent in children aged 10 to 14 years old with weight and height percentiles below the 25th percentile (p < 0.05). Comparison of means revealed no significant differences.

CONCLUSIONS

The prevalence of H. pylori infection found in our study was slightly lower than that found in other studies carried out in Spain; our data were more similar to those of industrialized countries. H. pylori infection was linked to age, sex and deprived socioeconomic environments, and was more frequent in children with recurrent abdominal pain and in those whose parents suffered from gastroduodenal disease. H. pylori infection did not seem to negatively affect growth in our child population.

Investigation of Helicobacter pylori infection in beta-thalassaemia major patients with recurrent abdominal pain

BACKGROUND

Recurrent abdominal pain (RAP) affects many children, especially those affected by beta-thalassaemia major. The role of Helicobacter pylori is still unclear in children with RAP.

OBJECTIVES

The aim of the present study was the comparison of beta-thalassaemia major patients and normal controls with RAP in H. pylori infection. The factors influencing H. pylori prevalence were also investigated.

METHODS

A series of 50 beta-thalassaemia major cases (30 female, 20 male; aged 6-25 years) and 50 age-matched and sex-matched controls, both presenting with RAP, were recruited during a period of 18 months. The study participants were obtained through a multistage random sampling method among those that met Apley's criteria. All the patients and controls had undergone diagnostic oesophagogastroduodenoscopy with biopsy. H. pylori infection was confirmed by two histopathological examinations on an endoscopy sample and a rapid urease test.

RESULTS

H. pylori infection in thalassaemic patients was more common than in controls [34/50 (68%) versus 30/50 (60%)], but this higher frequency was not statistically significant. A clear relationship was found between the prevalence of H. pylori and age, duration of transfusion/chelation programmes, pain duration and splenectomy. In contrast, H. pylori did not correlate with abdominal pain characteristics, blood group, serum ferritin level and pathology of the upper gastrointestinal tract. The most frequent endoscopy abnormality was gastritis (72%). Nausea and heartburn were the leading associated symptoms.

CONCLUSION

The high prevalence of H. pylori infection suggests that H. pylori should be remembered as a probable cause of RAP in beta-thalassaemia major patients.

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.

Heterogeneous susceptibility to metronidazole and clarithromycin of Helicobacter pylori isolates from a single biopsy in adults is confirmed in children

The aim of this study was to assess the resistance to metronidazole and clarithromycin of individual colonies of Helicobacter pylori from a single biopsy taken from 14 adults and 14 children. The Etest was used to determine the minimum inhibitory concentrations (MICs) of these two antimicrobial drugs for ten individual H. pylori colonies isolated from each initial gastric biopsy culture. We confirmed the heterogeneity in metronidazole and clarithromycin resistance in children as seen in adults before anti-H. pylori treatment. The number of resistant individual colonies ranged from two to nine depending on the subject. All individual colonies from the same biopsy that were resistant to clarithromycin were genetically identical according to randomly amplified polymorphic DNA testing and exhibited the same point mutation according to polymerase chain reaction-restriction fragment length polymorphism.

Helicobacter pylori and recurrent pain abdomen

OBJECTIVE

Pain abdomen is a common problem in childhood. Many factors i.e., organic changes in the gut, psychological and environment contribute to recurrent pain abdomen (RAP) in children. Helicobacter pylori infects children very early in childhood and stays indefinitely in the gut without its eradication. It may be responsible for pain abdomen and peptic ulcers in children. This study was done to assess the HP status in children with RAP diagnosed and evaluate the effects of eradication of HP infection in them.

METHODS

76 children were included in the study.

RESULT

Out of 76 children studied 14.8% had evidence of a secondary cause for pain abdomen and responded to appropriate therapy. 65.45% of children who had undergone UGIE, had evidence of HP infection in the upper gastrointestinal tract. Most of these children responded to HP eradication therapy by becoming free of abdominal pain after the eradication therapy with OCA or OMA regimen. We could not do repeated endoscopies in all of them to prove the eradication due to parents' refusal and this is the main drawback of this study.

CONCLUSION

However, in view of clinical response to HP eradication therapy in almost all the cases, we strongly advocate this therapy for those children with RAP, in whom HP infection of the upper gastrointestinal tract can be established beyond doubt.

Helicobacter pylori infection is not associated with specific symptoms in nonulcer-dyspeptic children

OBJECTIVES

To assess symptoms associated with Helicobacter pylori infection in children presenting with nonulcer dyspepsia (NUD).

STUDY DESIGN

A prospective double-blind study was conducted between March 2001 and April 2002 in children at least 6 years old with NUD who had been referred for upper gastrointestinal endoscopy for epigastric pain. A standardized questionnaire was administered blindly by a pediatric gastroenterologist. This questionnaire characterized epigastric pain and associated factors. Infection was confirmed by positive culture and histologic examination of the gastric mucosa.

RESULTS

From 100 children enrolled, 26 proved infected (12 female, 14 male; mean age: 11.4 +/- 2.6 years), and 74 were noninfected (44 female, 30 male; mean age: 10.4 +/- 3.1 years). There were no differences in age or symptom characteristics between groups except for epigastric pain during meals that was more frequent in noninfected than in infected children (25.6% vs 3.8%).

CONCLUSION

There were no specific characteristics of symptoms in nonulcer-dyspeptic H pylori-infected children as compared with noninfected children.

Review article: is there a link between micronutrient malnutrition and Helicobacter pylori infection?

Helicobacter pylori causes a chronic gastric infection, which is usually life-long. Many epidemiological studies have shown that this is probably one of the most common bacterial infections throughout the world involving 30% of the population living in developed countries and up to 80-90% of the population in developing regions. Concomitantly, developing regions also have high prevalence of micronutrient malnutrition. In the last few years, some studies have suggested that H. pylori infection may affect the homeostasis of different micronutrients including iron, vitamin B12, folic acid, alpha-tocopherol, vitamin C and beta-carotene. In this article, we discuss the current scientific information of the effect that H. pylori infection may produce on micronutrient malnutrition.

Helicobacter pylori infection in Turkish children: comparison of diagnostic tests, evaluation of eradication rate, and changes in symptoms after eradication

BACKGROUND

Helicobacter pylori infection is most frequently acquired in childhood. After this organism is eradicated, the rate of reinfection is low. Thus, it is very important to diagnose and treat the disease appropriately in childhood, and to be able to assess eradication with certainty. Eradication of H. pylori infection is reported to reduce or eliminate abdominal pain and dyspeptic symptoms in children.

PATIENTS AND METHODS

The study involved 102 children who had already been diagnosed with symptomatic H. pylori infection based on gastric histopathological examination, urea breath test, rapid urease test, serology and culture. Each patient's symptoms and family history of gastrointestinal problems were recorded. Using histology as the gold standard for identifying H. pylori infection, we determined the diagnostic sensitivity of each of the other methods. Omeprazole or lansoprazole, amoxicillin and clarithromycin were administered as eradication treatment, and each patient was re-evaluated by urea breath test 8 weeks later. Each child was re-interviewed about symptoms after treatment. These answers and the results of drug sensitivity testing were recorded. Cases of failed eradication were re-treated with a quadruple-drug regimen of tetracycline, metronidazole, bismuth subsalicylate and omeprazole.

RESULTS

The most frequent symptom was abdominal pain (89.2%). Fifty-four per cent of the subjects had a family history of dyspeptic symptoms. Sixty-six patients (64.7%) exhibited nodularity in the antral mucosa. The sensitivities of the diagnostic tests in histologically proven cases were as follows: urea breath test 100%, rapid urease test 89.2%, serology 71.9%, and culture 54.9%. Metronidazole had the highest frequency of resistance (36.4%) and the rate of clarithromycin resistance was 18.2%. The eradication rate after first-line therapy was 75.5%, and abdominal pain and dyspeptic symptoms were reduced or completely resolved in 75.7% of the successful-eradication cases. The proportion of failed-eradication cases that responded well to quadruple-drug therapy was 93.8%.

CONCLUSION

Symptomatic H. pylori infection in a child should always be treated. The urea breath test is an accurate and reliable way to identify H. pylori-positive patients and to determine the response to treatment. Triple-agent therapy is effective for eradicating H. pylori infection in children and usually helps reduce or eliminate dyspeptic symptoms. The level of H. pylori resistance to metronidazole is high in our region. The significant rate of resistance to clarithromycin (18.1%) may explain the treatment failure observed in this study.

The seroprevalence of Helicobacter pylori in a referral population of children in the United States

OBJECTIVES

The purpose of this study was to determine the prevalence of serum antibodies directed against Helicobacter pylori (H. pylori) in children referred to children's hospitals or medical centers throughout the United States.

METHODS

This multisite cross-sectional prospective study involved 992 children from 12 states using a validated anti-H. pylori IgG enzyme immunoassay. The children were recruited into two groups: those without any GI complaints (non-GI referral, n = 619) and those who were referred for endoscopy because of abdominal pain (GI referral, n = 373).

RESULTS

GI referral children had a higher rate of seropositivity (22.5%) than non-GI referral children (14.1%) from the same geographic regions. In both groups, older children were more likely to be seropositive for H. pylori, as were nonwhite children and those with lower socioeconomic status. H. pylori seropositivity rates were higher in GI referral children with four or more household members (relative risk [RR] = 1.47; CI 1.01-2.14). Multivariate analysis controlling for age, ethnicity, and household income, showed that presence of GI symptoms were associated with a nearly 2-fold risk for H. pylori seropositivity (odds ratio = 1.77, CI 1.27-2.47). Epigastric pain (RR = 2.21; CI = 1.33-3.66) and having three or more episodes of abdominal pain in the last 3 months (RR = 0.59, CI = 0.35-0.99) were the only specific symptoms significantly associated with H. pylori seropositivity.

CONCLUSIONS

The H. pylori seropositivity rate of GI referral children with symptoms of abdominal pain was significantly higher. H. pylori infection in early childhood was found to be associated primarily with the child's household size and socioeconomic status.

Serologic prevalence of antibodies to Helicobacter pylori in internationally adopted children

BACKGROUND

Helicobacter pylori (H. pylori) infection has been linked to gastritis, diarrhea, peptic ulcers, failure-to-thrive, anemia, as well as predisposition to gastric malignancies. Because many internationally adopted children have diarrhea, failure-to-thrive, and anemia on arrival to the US, we determined the prevalence of HP antibodies among these children.

METHODS

Serum samples from 226 unselected children from 18 countries who were evaluated in the International Adoption Clinic at New England Medical Center were tested for antibodies to H. pylori. The results of serologic screening were analyzed in relation to age at adoption, site of residence prior to adoption, weight and height, and the presence or absence of anemia, diarrhea, or intestinal parasites.

RESULTS

31% of internationally adopted children had antibodies to H. pylori. The presence of H. pylori-antibodies was associated with residence in an orphanage (vs. foster care) prior to adoption, older age at adoption, and coinfection with intestinal parasites. No direct effects on height or weight were identified; no associations with diarrhea or anemia were found.

CONCLUSIONS

Internationally adopted children have a high incidence of exposure to H. pylori, as diagnosed serologically. Residence in an orphanage (compared with foster care), older age at adoption, and coinfection with intestinal parasites were more common among children seropositive for anti-H. pylori antibodies.

Nodular gastritis in adults is caused by Helicobacter pylori infection

A close relationship exists between nodular gastritis and Helicobacter pylori infection in children. The pathogenesis and optimal management of nodular gastritis in adults, however, are unclear. This study describes the clinicopathologic features of nodular gastritis in adults and correlates treatment with outcome. Of 97,262 adult patients who underwent endoscopy, 187 (0.19%) were diagnosed with nodular gastritis, 151 (81%) of whom had dyspepsia. Nodular gastritis predominantly affects young women (49 men and 138 women, mean age, 32.6 years). All 134 patients tested for Helicobacter pylori infection were infected, and 65/66 (98%) had inflammation of both the antrum and the corpus. Twenty-five (13%) had associated lesions (peptic ulcers or cancer). Dyspepsia improved after eradication of Helicobacter pylori infection, but did not improve spontaneously. Nodular gastritis in adults is caused by Helicobacter pylori infection and shows a predilection for females and young adults. Helicobacter pylori eradication decreases symptoms and reduces the risk of peptic ulcers and possibly gastric cancer.

Foetal intrauterine growth restrictions with Helicobacter pylori infection

BACKGROUND

Helicobacter pylori infection has been associated with growth restriction in young children.

AIM

To determine whether there is an association between H. pylori infection and intrauterine growth restriction.

METHODS

Four hundred and forty-eight consecutive pregnant women (aged 15-44 years), attending for routine examinations in the third trimester, were enrolled. Clinical, demographic and previous obstetric data, as well as smoking history, were collected. At delivery, the weight, height, gender and status of the neonate were recorded; intrauterine growth restriction was defined if the birth weight was below the 10th percentile according to the gestational age for infants born in Australia.

RESULTS

Eighty-nine (20%) women were seropositive for H. pylori. The prevalence of H. pylori was significantly lower in Caucasians (17%) vs. non-Caucasians (42%, P < 0.0001). There were 34 (7.5%) cases of intrauterine growth restriction (7% Caucasians, 16% Asians, 12% Aborigines and 0% Pacific Islanders). Intrauterine growth restriction was more common in H. pylori-seropositive women than in H. pylori-seronegative women [13.5% vs. 6%; odds ratio (OR) = 2.41; 95% confidence interval (CI), 1.14-5.08; P = 0.018]. A multiple logistic regression model revealed that smoking (OR = 3.55; 95% CI, 1.62-7.79; P = 0.002), maternal height (OR = 0.48; 95% CI, 0.28-0.80; P = 0.005) and H. pylori seropositivity (OR = 2.59; 95% CI, 1.12-5.95; P = 0.025) were all independent risk factors for intrauterine growth restriction.

CONCLUSIONS

H. pylori infection in pregnant women may affect foetal intrauterine growth.

Helicobacter pylori infection in patients with idiopathic short stature

BACKGROUND

Some investigators have recently described an association between Helicobacter pylori infection and children with short stature. In the present study, we aimed to evaluate children with short stature with different etiologies.

METHODS

This study evaluated short patients aged from 1 to 16 years. These patients were divided into a growth hormone deficient short stature group (n = 27) and an idiopathic short stature group (n = 14). A control group included children with normal growth and no abdominal pain (n = 47). Anti-H. pylori antibodies were measured in each group (total of 88).

RESULTS

The antibody positivity rates for each group were as follows: growth hormone deficient short stature group, 7.4%; idiopathic short stature group, 28.6%; and control group, 6.4%. The H. pylori antibody positivity rate in the idiopathic short stature group was significantly higher than in the control group.

CONCLUSION

Our findings suggest an association between H. pylori infection and idiopathic short stature.

Five- to 7-year-old children with Helicobacter pylori infection are smaller than Helicobacter-negative children: a cross-sectional population-based study of 3,315 children

OBJECTIVE

To test whether Helicobacter pylori-positive children are smaller and weigh less than H pylori-negative children.

DESIGN

Cross-sectional population-based study.

PARTICIPANTS

In 3,315 5-to 7-year-old preschool and school children, the putative influence of H pylori infection on growth was investigated. Standing height and weight were analyzed in relation to H pylori infection. The diagnosis of H pylori infection was established by 13C-urea-breath test.

RESULTS

The prevalence of H pylori infection in boys was 7.2% (95% confidence interval, 5.9-8.9; n = 1,550) and in girls was 6.1% (95% confidence interval, 4.9-7.3; n = 1,552) H pylori-positive children were smaller than noninfected children (117.6 +/- 5.5 cm vs. 118.9 +/- 5.7 cm; P < 0.01). Although H pylori-positive boys were 2.06 cm smaller than H pylori-negative boys (117.4 +/- 5.6 cm vs. 119.5 +/- 5.7 cm; P < 0.001), the difference in girls was not significant (117.9 +/- 5.3 cm vs. 118.4 +/- 5.7 cm). When standing height was adjusted for age, the found differences were more pronounced. Differences between the infected and noninfected children with regard to body weight were not significant (22.4 +/- 4.0 kg vs. 22.1 +/- 4.0 kg), nor was there a significant difference with regard to body-mass index. However, boys with H pylori infection had a lower weight than noninfected boys (21.6 +/- 3.3 kg vs. 22.6 +/- 4.0 kg; P < 0.01), but in girls, these differences were not observed (22.2 +/- 4.0 vs. 22.8 +/- 4.6 kg, respectively). When weight was adjusted for age, H pylori -positive children also had a lower weight than H pylori -negative children because of the lower weight of boys.

CONCLUSIONS

H pylori infection is associated with growth delay, growth retardation, or both in affected children.

Helicobacter pylori infection and recurrent abdominal pain in Turkish children

BACKGROUND

Helicobacter pylori infection is primarily acquired in childhood. However, the association between H. pylori infection and recurrent abdominal pain (RAP) remains unclear.

MATERIALS AND METHODS

One hundred and forty-one children with and 21 without RAP underwent upper gastrointestinal endoscopy. At least five antral gastric biopsies were obtained from each patient and the presence of H. pylori infection was accepted when at least two out of four tests (histology, direct antral smear, culture, and rapid urease test) were positive. Patients with H. pylori infection underwent triple therapy with omeprazole, clarithromycin, and metronidazole.

RESULTS

Eighty-five out of 141 (60.3%) patients with RAP were H. pylori positive whereas 5 out of 21 (20.8%) patients without RAP were (p =.0037). Symptoms were disappeared in 87% of children whose H. pylori infection was eradicated compared with 41% of those in whom the infection was not eradicated (p =.0035).

CONCLUSIONS

It was concluded that children with RAP and H. pylori infection appear to benefit from eradication therapy in Turkey.

Familial and community environmental risk factors for Helicobacter pylori infection in children and adolescents

BACKGROUND

The aim of the study was to identify familial and community environmental risk factors associated with Helicobacter pylori infection in a pediatric population.

METHODS

Children requiring diagnostic upper endoscopy were included in the study during a 2-year period. During endoscopy, five gastric biopsies were performed for the histologic or bacteriologic diagnosis, or both, of H. pylori infection. Epidemiologic data collected by a questionnaire were analyzed using the chi-square test or Fisher test and stepwise logistic regression.

RESULTS

The authors included 436 patients (242 boys), aged 2 days to 17.9 years (median, 2.7 years). H. pylori prevalence was 7.3%. Univariate analysis found H. pylori was more common in older patients (P < 0.00001), in children who had at least one parent born in a developing country (P < 0.02) or with a low socioeconomic status (P < 0.02), and in those living in crowded conditions (P < 0.02). Children whose mother worked at home were more frequently infected than children whose mother worked outside the home (P < 0.02). Attendance at nursery or school before the age of 6 years was not associated with infection. Logistic regression showed a strong association with H. pylori only for age and number of persons at home.

CONCLUSIONS

The source of H. pylori is intrafamilial rather than from a community, such as nursery and school attended at a young age. The number of persons in the home influences the infection status of children but not by the presence of the mother in home. These data suggest that H. pylori infection transmission occurs from siblings or the father rather than from mother.

Helicobacter pylori in school children from the Western province of Sri Lanka

BACKGROUND

Little is known about the prevalence of Helicobacter pylori in Sri Lanka and nothing is known about its prevalence in children. Therefore the prevalence of H. pylori in a group of school children in Sri Lanka was determined.

MATERIALS AND METHODS

The presence of H. pylori colonisation was determined by detection of faecal antigen and salivary antibody (IgG) by enzyme immuno assay, in 184 children aged between 5 and 19 years, in the Western Province-Colombo district of Sri Lanka.

RESULTS

Overall, only 12/184 (6.5%) had detectable H. pylori antigen in their stools and were considered infected with H. pylori, while 51/184 (27.7%) had H. pylori IgG in saliva. H. pylori salivary IgG declined with age while H. pylori antigen detection increased with age. H. pylori infection, as determined by salivary antibody (66%), was greater in children living in overcrowded conditions, although this was not statistically significant.

CONCLUSION

The prevalence of H. pylori among school children in Sri Lanka was 6.5% by detection of faecal antigen and 27.7% by detection of salivary antibody, respectively. Initial infection with H. pylori appeared to occur in early childhood whilst active disease began in late childhood. Overcrowding appears to facilitate the transmission of the organism. Overall the prevalence of H. pylori was low in Sri Lanka compared with other countries in South-east Asia.

Helicobacter pylori infection in children with constitutional delay of growth and puberty

Helicobacter pylori is a gastroduodenal pathogen strongly associated with chronic gastritis and duodenal ulceration. It is thought that H. pylori infection might be one of the causes of growth retardation in children. The aim of this study was to evaluate the seroprevalence of H. pylori in children with constitutional delay of growth and puberty (CDGP). H. pylori seropositivity was studied in 24 children with CDGP (22 M, 2 F) and 32 healthy age-matched children with normal pubertal development. Mean age of the children with CDGP was 14.53 +/- 1.12 yr and all of them had been diagnosed as CDGP after physical and laboratory assessment. H. pylori IgG positivity was detected in 16 of the 24 children with CDGP (66.6%) and 12 of 32 controls (37.5%) (p <0.05). This finding is consistent with the hypothesis that H. pylori infection could be one of the environmental factors causing CDGP.

An association between sudden infant death syndrome (SIDS) and Helicobacter pylori infection

BACKGROUND

Helicobacter pylori has recently been detected in the stomach and trachea of cases of sudden infant death syndrome (SIDS) and proposed as a cause of SIDS.

AIMS

To establish the incidence of H pylori in the stomach, trachea, and lung of cases of SIDS and controls.

METHODS

Stomach, trachea, and lung tissues from 32 cases of SIDS and eight control cases were examined retrospectively. Diagnosis of SIDS was based on established criteria. Controls were defined by death within 1 year of age and an identifiable cause of death. Tissues were examined histologically for the presence of bacteria. Extracted DNA from these tissues was tested for H pylori ureC and cagA sequences by nested polymerase chain reaction and amplicons detected by enzyme linked immunosorbent assay (ELISA). The cut off for each ELISA for each of the tissue types was taken as the mean optical density plus two times the standard deviation of a range of negative controls.

RESULTS

Ages of SIDS cases ranged from 2 to 28 weeks. Ages of controls ranged from 3 to 44 weeks. For the ureC gene, 25 SIDS cases were positive in one or more tissues compared with one of the controls. For the cagA gene, 25 SIDS cases were positive in one or more tissues compared with one of the controls.

CONCLUSIONS

There is a highly significant association between H pylori ureC and cagA genes in the stomach, trachea, and lung of cases of SIDS when compared with controls.

Helicobacter pylori infection in children of Texas

BACKGROUND

Acquisition of the Helicobacter pylori infection usually occurs in childhood. The prevalence of infection differs among ethnic groups and in adults is inversely related to the socioeconomic status of the individual's family during childhood. This study investigates the seroprevalence of H. pylori infection in children of different ethnic groups in relation to socioeconomic class and investigates the prevalence of acute H. pylori infection among children who have had recent onset of abdominal pain.

METHODS

Serum samples were collected from 797 children, aged 6 months to 18 years, of various socioeconomic and ethnic backgrounds, at a large urban children's hospital. H. pylori status was determined by an anti-H. pylori immunoglobulin (Ig)G enzyme-linked immunosorbent assay (ELISA) validated for pediatric use. To determine the prevalence of acute H. pylori infection, children brought to the emergency center with abdominal symptoms without diarrhea and overt signs of acute abdomen were evaluated with both serology and the 13C-urea breath test. Acute H. pylori was defined as a positive 13C-urea breath test result and negative IgG serology for H. pylori.

RESULTS

The overall seroprevalence of H. pylori was 12.2% and increased with age (e.g., 8.3% at 6-11.9 months and 17.9% at 13 years). The prevalence was inversely related to socioeconomic status (6.6%, moderate to high vs. 15%, low socioeconomic status). The difference in seroprevalence among blacks (16.8%), Hispanics (13.3%), and whites (8.3%; P < 0.01) could be accounted for by differences in socioeconomic status. Eighteen percent of children who were evaluated at the emergency center for recent-onset abdominal pain had acute H. pylori infections.

CONCLUSIONS

Socioeconomic status, not ethnic group, is the more important risk factor for acquisition of H. pylori infection during childhood. Acute H. pylori infection was a relatively common cause of recent-onset, nonsurgical abdominal pain.

Relevance of CagA positivity to clinical course of Helicobacter pylori infection in children

A potential virulence determinant of Helicobacter pylori is the cagA gene product. To determine the relevance of the expression of CagA to the clinical picture and outcome of H. pylori infection in children, we examined 104 consecutive children diagnosed with H. pylori infection. Serum samples were collected to test for the presence of immunoglobulin G (IgG) anti-CagA antibodies. Forty-five patients (43%) had antibodies to the CagA protein (group I), and 59 did not (group II). Seropositive patients had a longer prediagnostic history of abdominal pain (P = 0.02), more severe abdominal pain (defined as ulcer pain) (P = 0.05), a higher prevalence of duodenal ulcer (38 versus 7%; P<0.01), more active chronic gastritis (82 versus 32%; P<0.001), and a higher titer of serum IgG anti-H. pylori antibodies (P<0.001). Ninety percent of the patients were monitored for 27+/-18 months. On multivariate analysis, CagA-negative patients had a 3.8-fold-higher chance of achieving a disease-free state than CagA-positive patients (95% confidence interval, 1.5- to 9.5-fold). We conclude that infection with CagA-producing strains of H. pylori is a risk factor for severe clinical disease and ongoing infection.

A comprehensive review of the natural history of Helicobacter pylori infection in children

Across populations of children, Helicobacter pylori prevalence ranges from under 10% to over 80%. Low prevalence occurs in the U.S., Canada, and northern and western Europe; high prevalence occurs in India, Africa, Latin America, and eastern Europe. Risk factors include socioeconomic status, household crowding, ethnicity, migration from high prevalence regions, and infection status of family members. H. pylori infection is not associated with specific symptoms in children; however, it is consistently associated with antral gastritis, although its clinical significance is unclear. Duodenal ulcers associated with H. pylori are seldom seen in children under 10 years of age. H. pylori-infected children demonstrate a chronic, macrophagic, and monocytic inflammatory cell infiltrate and a lack of neutrophils, as compared with the response observed in adults. The effect of H. pylori infection on acid secretion in children remains poorly defined. The events that occur during H. pylori colonization in children should be studied more thoroughly and should include urease activity, motility, chemotaxis, adherence, and downregulation of the host response. The importance of virulence determinants described as relevant for disease during H. pylori infection has not been extensively studied in children. Highly sensitive and specific methods for the detection of H. pylori in children are needed, especially in younger pediatric populations in which colonization is in its early phases. Criteria for the use of eradication treatment in H. pylori-infected children need to be established. Multicenter pediatric studies should focus on the identification of risk factors, which can be used as prognostic indicators for the development of gastroduodenal disease later in life.

A study of the interaction between Helicobacter pylori and components of the human fibrinolytic system

The interaction of plasminogen, tissue plasminogen activator (t-PA) and urokinase with a clinical strain of Helicobacter pylori was studied. Plasminogen bound to the surface of H. pylori cells in a concentration-dependent manner and could be activated to the enzymatic form, plasmin, by t-PA. Affinity chromatography assays revealed a plasminogen-binding protein of 58.9 kDa in water extracts of surface proteins. Surface-associated plasmin activity, detected with the chromogenic substrate CBS 00.65, was observed only when plasminogen and an exogenous activator were added to the cell suspension. The two physiologic plasminogen activators, t-PA and urokinase, were also shown to bind to and remain active on the surface of bacterial cells. epsilon-Aminocaproic acid caused partial inhibition of t-PA binding, suggesting that the kringle 2 structure of this activator is involved in the interaction with surface receptors. The activation of plasminogen by t-PA, but not urokinase, strongly depended on the presence of cells and a 25-fold enhancer effect on the initial velocity of activation by t-PA compared to urokinase was established. Furthermore, a relationship between cell concentration and the initial velocity of activation was demonstrated. These findings support the concept that plasminogen activation by t-PA on the bacterial surface is a surface-dependent reaction which offers catalytic advantages.

Implications of Helicobacter pylori infection for stomach cancer prevention

Accumulating evidence has implicated Helicobacter pylori, an established cause of chronic gastritis and peptic ulcer, in the etiology of gastric cancer. Control of this infection would reduce the occurrence of chronic gastritis and peptic ulcer and might substantially lower the risk of stomach cancer as well. The public health impact of this infectious agent warrants efforts to identify preventive measures. This paper reviews the evidence linking H. pylori infection to gastric cancer and evaluates the potential for control in high-risk populations. Current obstacles to H. pylori control are discussed, including the link to poor socioeconomic conditions, difficulty in identifying incident cases, lack of natural immunity to reinfection, limited effectiveness of antibiotic therapy in high-prevalence populations, and incomplete knowledge regarding the reservoir of infection, mode of transmission, host susceptibility factors, and the potential for developing an effective vaccine. Worthwhile avenues of research include studies designed to identify modifiable risk factors for acquisition of the infection, modifiable host factors that may increase resistance to chronic infection, more effective antibiotic therapies, and effective vaccines.