Comparison of non-invasive tests to detect Helicobacter pylori infection in children and adolescents: results of a multicenter European study

Helicobacter pylori Infection, Its Laboratory Diagnosis, and Antimicrobial Resistance: a Perspective of Clinical Relevance

Despite the recent decrease in overall prevalence of Helicobacter pylori infection, morbidity and mortality rates associated with gastric cancer remain high. The antimicrobial resistance developments and treatment failure are fueling the global burden of H. pylori-associated gastric complications. Accurate diagnosis remains the opening move for treatment and eradication of infections caused by microorganisms. Although several reports have been published on diagnostic approaches for H. pylori infection, most lack the data regarding diagnosis from a clinical perspective. Therefore, we provide an intensive, comprehensive, and updated description of the currently available diagnostic methods that can help clinicians, infection diagnosis professionals, and H. pylori researchers working on infection epidemiology to broaden their understanding and to select appropriate diagnostic methods. We also emphasize appropriate diagnostic approaches based on clinical settings (either clinical diagnosis or mass screening), patient factors (either age or other predisposing factors), and clinical factors (either upper gastrointestinal bleeding or partial gastrectomy) and appropriate methods to be considered for evaluating eradication efficacy. Furthermore, to cope with the increasing trend of antimicrobial resistance, a better understanding of its emergence and current diagnostic approaches for resistance detection remain inevitable.

The relationship between helicobacter pylori infection and nodular antral gastritis in pediatric patients

BACKGROUND

Helicobacter pylori (H. pylori) is a spiral-shaped gram-negative bacterium that colonizes the gastric mucosa. It is a common infectious agent in children. In this study, we aim to evaluate the demographic data, and the clinical and histopathological findings of pediatric patients that underwent upper gastrointestinal endoscopy (UGSE) in our clinic.

METHODS

Between July 2017 and February 2019, 636 patients applied to the Selcuk University Faculty of Medicine, Pediatric Gastroenterology outpatient clinic with complaints of epigastric abdominal pain and/or dyspeptic complaints. Patients who underwent upper gastrointestinal endoscopy were evaluated retrospectively. Data on age, gender, family history of peptic ulcer disease, and family history of H. pylori were recorded. Endoscopic and histopathological findings were collected from medical records.

RESULTS

235 (36.9%) of the patients participating in the study were male, and 401 (63.1%) were female. H. pylori infection was detected in 277 (43.6%) patients as a result of histopathological examination of H. Pylori, urea breath tests and H. Pylori antigen tests in the stools of patients are included in the study. Nodular antral gastritis was detected in 282 (44.3%) of our patients endoscopically. H. pylori was detected in 83.7% (n: 236) of the 282 patients with nodular antral gastritis. Nodular antral gastritis was observed to be significantly higher in H. pylori-positive patients than in H. pylori-negative cases (odds ratio (OR), 39.16; 95% confidence interval (CI), 24.88-61.64; p: <0.001).

CONCLUSION

Nodular antral gastritis is caused by chronic H. pylori infection. It is predicted that early detection of H. pylori infection in children is important and may decrease complications later in life. Our study shows that all the markers evaluated are very good predictors of H. pylori infection. Positive significant association was found between the prevalence of H. pylori infection and nodular antral gastritis.

Prevalence of Helicobacter pylori among children in a training and research hospital clinic in Istanbul and comparison with Updated Sydney Classification Criteria

OBJECTIVE

Helicobacter pylori (H. pylori) is a gram-negative bacterium and one of the reasons for gastritis, peptic and duodenal ulcers. It is a crucial public health problem for both children and adults, especially in developing countries. This study aims to investigate the prevalence of Helicobacter pylori positivity in children and to compare with updated Sydney classification criteria.

METHODS

This study was conducted from January 2015 to June 2017. This study included 885 children aged 0-17 year(s). Endoscopic biopsies were evaluated for the diagnosis of infection due to H. pylori.

RESULTS

The findings showed that 418 (47.2%) of 885 children were positive for H. pylori, and this positivity had a significantly increasing correlation with the presence of chronic inflammation, neutrophilic activity, lymphoid aggregates, and follicles. Erythematous pangastritis and antral nodularity on endoscopic findings had a correlation with H. pylori positivity.

CONCLUSION

In this hospital-based study, the findings suggest that H. pylori infection is a problem for children and more extensive studies are needed to determine the prevalence of H. pylori positivity among children.

Helicobacter pylori infection in children: an overview of diagnostic methods

Children differ from adults regarding Helicobacter pylori (H. pylori) infection in many terms. H. pylori infection represents a key factor in the pathogenesis of duodenal ulcer and chronic gastritis in children. H. pylori infection causes some extraintestinal diseases as well as gastrointestinal diseases. Although, among these illnesses in children, symptoms like recurrent abdominal pain are not specific. Moreover, the role of the pathogen in the growth faltering, iron deficiency anemia, and asthma still remains controversial. A reliable method to detect H. pylori infection is a crucial issue, sand is still a matter of active debate. The tests applied for H. pylori diagnosis are grouped as either invasive or non-invasive methods. Invasive methods consist of endoscopic evaluation, the rapid urease test (RUT), histology, and bacterial culture. Non-invasive tests include the urea breath test (UBT), stool antigen test (SAT), serology, and molecular diagnostic approaches. Use of endoscopy is a pre-requisite for all invasive methods and poses difficulties in children as it is a difficult procedure and requires patient's cooperation. For this reason, the non-invasive tests have been commonly used in children, although their accuracy is not very reliable in some cases. Invasive tests may be opted to confirm the diagnosis as and when needed. This review presents the diagnostic tests used to detect H. pylori infection in children.

Helicobacter pylori Infection in Children and Adolescents

About one-third of all children worldwide is infected with H. pylori and its prevalence is low in developed and high in developing countries. H. pylori is mainly acquired during childhood and transmission of the bacterium commonly proceeds from person to person, especially among family members. The most frequent transmission route is from the mother to children. Various gastrointestinal and extra-gastrointestinal diseases are reported to be associated with H. pylori in children and adolescents, but the strongest recommendation for testing and treating is introduced only with children and adolescents having peptic ulcer disease. Iron deficiency anemia and chronic immune thrombocytopenic purpura are also considered for testing and treating, but the effectiveness is somewhat controversial. Invasive diagnosis is recommended, whereas none of the available diagnostic tests have 100% accuracy for reliable diagnosis, and therefore at least two or more tests should be performed. Urea breath test is the most reliable among the non-invasive tests. Because the number of antibiotics-resistant H. pylori strains is increasing, it is desirable to conduct a drug susceptibility test before treatment and to select the corresponding regime. H. pylori has been proven to be a major cause of gastric cancer and 'screen-and-treat' strategies are recommended in communities at high risk of gastric cancer. However, the application to children and adolescents is controversial. An effective vaccine is desirable, but not yet available. Screen-and-treat for adolescents has started in a few areas in Japan, where conditions are well established. New prevention strategies for gastric cancer are awaited worldwide.

Diagnostic Accuracy of Latex Agglutination Turbidimetric Immunoassay in Screening Adolescents for Helicobacter pylori Infection in Japan

BACKGROUND/AIMS

Serologic tests are commonly used for screening Helicobacter pylori infection because they not only provide quick results but also are inexpensive. A new latex agglutination serum antibody assay (LZ test) has been developed and it is expected to be as effective as conventional assays. This study aimed to calculate a reliable cutoff value for the LZ test and to estimate the sensitivity and specificity of the cutoff value in screening adolescents for H. pylori infection in Japan.

METHODS

We screened junior high school students in Akita Prefecture, Japan, for H. pylori infection. We used the data of 213 such students who underwent H. pylori stool antigen (HpSA) tests in 2016. The students who had positive results with HpSA tests were diagnosed with H. pylori infection. Of the 213 students, 209 underwent the LZ test.

RESULTS

The prevalence rate of H. pylori infection was 3.8% (8/209). The area under the curve for the LZ test was 0.88. The cutoff value of the LZ test was determined to be 3.1 U/mL. At this value, the sensitivity and specificity were 87.5 and 91.5%, respectively.

CONCLUSION

The accuracy of the LZ test in adolescents was well balanced for sensitivity and specificity as well as for tolerable results.

The fourth Mexican consensus on Helicobacter pylori

Important advances have been made since the last Mexican consensus on the diagnosis and treatment of Helicobacter pylori (H. pylori) infection was published in 2007. Therefore, the Asociación Mexicana de Gastroenterología summoned 20 experts to produce "The Fourth Mexican Consensus on Helicobacter pylori". From February to June 2017, 4 working groups were organized, a literature review was performed, and 3 voting rounds were carried out, resulting in the formulation of 32 statements for discussion and consensus. From the ensuing recommendations, it was striking that Mexico is a country with an intermediate-to-low risk for gastric cancer, despite having a high prevalence of H. pylori infection. It was also corroborated that peptic ulcer disease, premalignant lesions, and histories of gastric cancer and mucosa-associated lymphoid tissue lymphoma should be considered clear indications for eradication. The relation of H. pylori to dyspeptic symptoms continues to be controversial. Eradication triple therapy with amoxicillin, clarithromycin, and a proton pump inhibitor should no longer be considered first-line treatment, with the following 2 options proposed to take its place: quadruple therapy with bismuth (proton pump inhibitor, bismuth subcitrate, tetracycline, and metronidazole) and quadruple therapy without bismuth (proton pump inhibitor, amoxicillin, clarithromycin, and metronidazole). The need for antimicrobial sensitivity testing when 2 eradication treatments have failed was also established. Finally, the promotion of educational campaigns on the diagnosis and treatment of H. pylori for both primary care physicians and the general population were proposed.

Non-invasive diagnostic tests for Helicobacter pylori infection

BACKGROUND

Helicobacter pylori (H pylori) infection has been implicated in a number of malignancies and non-malignant conditions including peptic ulcers, non-ulcer dyspepsia, recurrent peptic ulcer bleeding, unexplained iron deficiency anaemia, idiopathic thrombocytopaenia purpura, and colorectal adenomas. The confirmatory diagnosis of H pylori is by endoscopic biopsy, followed by histopathological examination using haemotoxylin and eosin (H & E) stain or special stains such as Giemsa stain and Warthin-Starry stain. Special stains are more accurate than H & E stain. There is significant uncertainty about the diagnostic accuracy of non-invasive tests for diagnosis of H pylori.

OBJECTIVES

To compare the diagnostic accuracy of urea breath test, serology, and stool antigen test, used alone or in combination, for diagnosis of H pylori infection in symptomatic and asymptomatic people, so that eradication therapy for H pylori can be started.

SEARCH METHODS

We searched MEDLINE, Embase, the Science Citation Index and the National Institute for Health Research Health Technology Assessment Database on 4 March 2016. We screened references in the included studies to identify additional studies. We also conducted citation searches of relevant studies, most recently on 4 December 2016. We did not restrict studies by language or publication status, or whether data were collected prospectively or retrospectively.

SELECTION CRITERIA

We included diagnostic accuracy studies that evaluated at least one of the index tests (urea breath test using isotopes such as 13C or 14C, serology and stool antigen test) against the reference standard (histopathological examination using H & E stain, special stains or immunohistochemical stain) in people suspected of having H pylori infection.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the references to identify relevant studies and independently extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We performed meta-analysis by using the hierarchical summary receiver operating characteristic (HSROC) model to estimate and compare SROC curves. Where appropriate, we used bivariate or univariate logistic regression models to estimate summary sensitivities and specificities.

MAIN RESULTS

We included 101 studies involving 11,003 participants, of which 5839 participants (53.1%) had H pylori infection. The prevalence of H pylori infection in the studies ranged from 15.2% to 94.7%, with a median prevalence of 53.7% (interquartile range 42.0% to 66.5%). Most of the studies (57%) included participants with dyspepsia and 53 studies excluded participants who recently had proton pump inhibitors or antibiotics.There was at least an unclear risk of bias or unclear applicability concern for each study.Of the 101 studies, 15 compared the accuracy of two index tests and two studies compared the accuracy of three index tests. Thirty-four studies (4242 participants) evaluated serology; 29 studies (2988 participants) evaluated stool antigen test; 34 studies (3139 participants) evaluated urea breath test-13C; 21 studies (1810 participants) evaluated urea breath test-14C; and two studies (127 participants) evaluated urea breath test but did not report the isotope used. The thresholds used to define test positivity and the staining techniques used for histopathological examination (reference standard) varied between studies. Due to sparse data for each threshold reported, it was not possible to identify the best threshold for each test.Using data from 99 studies in an indirect test comparison, there was statistical evidence of a difference in diagnostic accuracy between urea breath test-13C, urea breath test-14C, serology and stool antigen test (P = 0.024). The diagnostic odds ratios for urea breath test-13C, urea breath test-14C, serology, and stool antigen test were 153 (95% confidence interval (CI) 73.7 to 316), 105 (95% CI 74.0 to 150), 47.4 (95% CI 25.5 to 88.1) and 45.1 (95% CI 24.2 to 84.1). The sensitivity (95% CI) estimated at a fixed specificity of 0.90 (median from studies across the four tests), was 0.94 (95% CI 0.89 to 0.97) for urea breath test-13C, 0.92 (95% CI 0.89 to 0.94) for urea breath test-14C, 0.84 (95% CI 0.74 to 0.91) for serology, and 0.83 (95% CI 0.73 to 0.90) for stool antigen test. This implies that on average, given a specificity of 0.90 and prevalence of 53.7% (median specificity and prevalence in the studies), out of 1000 people tested for H pylori infection, there will be 46 false positives (people without H pylori infection who will be diagnosed as having H pylori infection). In this hypothetical cohort, urea breath test-13C, urea breath test-14C, serology, and stool antigen test will give 30 (95% CI 15 to 58), 42 (95% CI 30 to 58), 86 (95% CI 50 to 140), and 89 (95% CI 52 to 146) false negatives respectively (people with H pylori infection for whom the diagnosis of H pylori will be missed).Direct comparisons were based on few head-to-head studies. The ratios of diagnostic odds ratios (DORs) were 0.68 (95% CI 0.12 to 3.70; P = 0.56) for urea breath test-13C versus serology (seven studies), and 0.88 (95% CI 0.14 to 5.56; P = 0.84) for urea breath test-13C versus stool antigen test (seven studies). The 95% CIs of these estimates overlap with those of the ratios of DORs from the indirect comparison. Data were limited or unavailable for meta-analysis of other direct comparisons.

AUTHORS' CONCLUSIONS

In people without a history of gastrectomy and those who have not recently had antibiotics or proton ,pump inhibitors, urea breath tests had high diagnostic accuracy while serology and stool antigen tests were less accurate for diagnosis of Helicobacter pylori infection.This is based on an indirect test comparison (with potential for bias due to confounding), as evidence from direct comparisons was limited or unavailable. The thresholds used for these tests were highly variable and we were unable to identify specific thresholds that might be useful in clinical practice.We need further comparative studies of high methodological quality to obtain more reliable evidence of relative accuracy between the tests. Such studies should be conducted prospectively in a representative spectrum of participants and clearly reported to ensure low risk of bias. Most importantly, studies should prespecify and clearly report thresholds used, and should avoid inappropriate exclusions.

When is Helicobacter pylori acquired in populations in developing countries? A birth-cohort study in Bangladeshi children

Helicobacter pylori colonization is prevalent throughout the world, and is predominantly acquired during childhood. In developing countries, >70% of adult populations are colonized with H. pylori and >50% of children become colonized before the age of 10 years. However, the exact timing of acquisition is unknown. We assessed detection of H. pylori acquisition among a birth cohort of 105 children in Mirzapur, Bangladesh. Blood samples collected at time 0 (cord blood), and at 6, 12, 18, and 24 months of life were examined for the presence of IgG and IgA antibodies to whole cell H. pylori antigen and for IgG antibodies to the CagA antigen using specific ELISAs and immunoblotting. Breast milk samples were analyzed for H. pylori-specific IgA antibodies. Cord blood was used to establish maternal colonization status. H. pylori seroprevalence in the mothers was 92.8%. At the end of the two-year follow-up period, 50 (47.6%) of the 105 children were positive for H. pylori in more than one assay. Among the colonized children, CagA prevalence was 78.0%. A total of 58 children seroconverted: 50 children showed persistent colonization and 8 (7.6%) children showed transient seroconversion, but immunoblot analysis suggested that the transient seroconversion observed by ELISA may represent falsely positive results. Acquisition of H. pylori was not influenced by the mother H. pylori status in serum or breastmilk. In this population with high H. pylori prevalence, we confirmed that H. pylori in developing countries is detectable mainly after the first year of life.

Rapid urine antibody test for Helicobacter pylori infection in adolescents

BACKGROUND

Helicobacter pylori infection is associated with gastric cancer; thus, early diagnosis and treatment are crucial. Given that H. pylori infection in adolescents or young adults has few symptoms, screening tests are necessary for this population. In this study, the accuracy of the rapid urine H. pylori antibody (u-HpAb) test was evaluated and compared with that of urine and serum H. pylori enzyme-linked immunosorbent assay (u-HpELISA and s-HpELISA, respectively) in junior high school students.

METHODS

All 1,225 students attending the junior high schools in Sasayama City were invited to participate in this study. Urine and blood samples were assayed for anti-H. pylori immunoglobulin G antibodies, and rapid u-HpAb was performed by three investigators independently. When all investigators were in agreement, the test was confirmed as positive or negative. Non-concordance was defined as undetermined.

RESULTS

In total, 187 students participated in this study and provided both urine and blood samples. Three students had undetermined rapid u-HpAb. Excluding these results, the positivity rate of rapid u-HpAb was 3.3% (6/184), whereas that for u-HpELISA and s-HpELISA was 4.8% (10/187) and 5.9% (11/187), respectively. Using s-HpELISA and u-HpELISA as the standards, the sensitivity, specificity, positive predictive value, and negative predictive value of rapid u-HpAb were 85.7%, 100%, 100%, and 99.4%, respectively, excluding the undetermined rapid u-HpAb results.

CONCLUSIONS

Rapid urine-HpAb test had excellent specificity but relatively low sensitivity.

Accuracy of testing for anti-Helicobacter pylori IgG in urine for H. pylori infection diagnosis: a systematic review and meta-analysis

OBJECTIVES

This meta-analysis aims to systematically measure the potential diagnostic value of anti-Helicobacter pylori IgG in urine for infection diagnosis, using all eligible studies published in English and Chinese languages.

DESIGN

The random effect model was used to analyse the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative LR (NLR), diagnostic OR (DOR), together with the summary receiver operator characteristic curve.

SETTING

Literature searches of databases including PubMed, EMBASE, MEDLINE, Web of Science, Chinese National Knowledge Infrastructure and Wanfang databases were performed to retrieve studies evaluating the diagnostic value of urine IgG antibody for H.pylori infection.

PRIMARY OUTCOME MEASURE

Twenty-three studies with 4963 subjects were included in the current meta-analysis.

RESULTS

The pooled sensitivity, specificity, PLR, NLR, DOR and area under the curve (AUC) were 0.83 (95% CI 0.82 to 0.85), 0.89 (95% CI 0.88 to 0.90), 8.81 (95% CI 6.37 to 12.2), 0.13 (95% CI 0.09 to 0.2), 73 (95% CI 46.45 to 114.74) and 0.9551, respectively. Subgroup analyses showed that diagnostic accuracy of the urine IgG assay was no different in age, region, study population and assay method.

CONCLUSIONS

Anti-H. pylori antibody in urine might serve as a good marker in diagnosing H. pylori infection. However, further validation based on a larger sample is still required.

Prevalence of helicobacter pylori infection among children living in a rural setting in Sub-Saharan Africa

BACKGROUND

Helicobacter pylori infection affects more than half of the world's population. It is generally acquired during childhood with no symptoms but has long- term clinical sequelae. This study estimated the prevalence of H. pylori infection amongst children in a rural environment in Africa.

METHODS

We conducted a cross-sectional study over a four (4)-month period within two rural communities. 240 asymptomatic children were tested using lateral flow immunochromatographic assay for the qualitative detection of H. pylori antigen in a fecal specimen. Statistical analysis and processing was done using Stata version 11.

RESULTS

The mean age of the participants was 10.5 ± 2.7 years with the predominant age range being 8-10 years (34.6%), and a mean household size of 7.1 ± 1.7. The study population showed a female preponderance of 57.1%. 88% of the H. pylori positive children lacked pipe and borehole drinking water. All of the positive H. pylori children practiced open-air defecation. The overall prevalence of H. pylori infection among children in this study was at least 14.2%.

CONCLUSION

Our study demonstrated a high prevalence of H. pylori infection among children in a rural setting. Educational status of parents did not affect H. pylori prevalence but increasing household numbers, female gender, source of drinking water other than pipe and borehole, open-air defecation and younger age were associated with a higher H. pylori prevalence.

The All-Age Prevalence of Helicobacter pylori Infection and Potential Transmission Routes. A Population-Based Study

BACKGROUND AND AIMS

Previous research on H. pylori epidemiology has mostly focused on adult populations. We have aimed to study H. pylori prevalence in all age groups including children and adolescents and to identify potential routes of transmission.

METHODS

Subjects from all age groups (children 0-11 years, adolescents 12-17 years and adults ≥18 years of age), recruited from both an urban and a rural community in Northern Norway, were invited to provide stool samples for the diagnosis of H. pylori antigen and to fill in a questionnaire (adult and adolescents only) on gastrointestinal symptoms, lifestyle factors and biometric data.

RESULTS

A total of 1 624 (35.3%) of the invited subjects, including 173 (39.3%) of the children, 46 (19.2%) of the adolescents, and 1 416 (36.1%) of the adults, responded to the invitation. H. pylori infection was nearly undetectable (0.6%) among the children, whereas the prevalence increased from 20% in adolescents toward a peak of 45% in the highest age group. Univariate analyses of possible risk factors of H. pylori infection showed significant associations to private well water, the use of outhouse toilet, and having farm animals in childhood, but the associations waned in multivariate analyses.

CONCLUSIONS

In our populations, with apparent high hygienic standards, the transmission of H. pylori infection may start not only in childhood, but also in adolescence, where potential transmission routes may be outdoor toilet use, private well water, and farm animals.

Helicobacter pylori Infection in Children: Nutritional Status and Associations with Serum Leptin, Ghrelin, and IGF-1 Levels

BACKGROUND

Helicobacter pylori is associated with gastrointestinal diseases such as gastritis, peptic ulcers, malignancy and lymphoma, and extra-gastrointestinal conditions. H. pylori infection is negatively associated with children's growth. Chronic inflammation of the stomach that results in the loss of appetite and, dysregulation of neuroendocrine hormones such as leptin, and ghrelin are the probable reasons of this negative association. The objective of this study is to determine the serum levels of leptin, ghrelin, and IGF-1 in H. pylori-infected children and their relations with growth.

MATERIALS AND METHODS

A hundred and sixty-one school children aged between 6 and 14 years were selected randomly from five primary schools representing a cross section of population. Demographic and sociocultural characteristics, and anthropometric measurements were recorded. Serum H. pylori IgG, insulin-like growth factor-1, leptin, and ghrelin levels were measured in all children. The children were grouped according to the nutritional status and Helicobacter pylori seropositivity. Nutritional indices were compared among groups in association with serum leptin, ghrelin, and insulin-like growth factor-1 levels.

RESULTS

H. pylori IgG positivity was found in 34.2%, and 14.9% of children were malnourished. H. pylori seropositivity was significantly higher in older ages (10.32 ± 2.26 vs 9.53 ± 2.36 years, p = .036), and body weight and height Z scores were significantly lower in H. pylori-seropositive children (-0.33 ± 1.08 vs 0.04 ± 1.26, p = .044 and 0.13 ± 0.92 vs 0.23 ± 0.91, p = .018 respectively). H. pylori seropositivity was found to be an independent risk factor for shorter body height (p = .01). Serum leptin, ghrelin, and IGF-1 levels were not associated with H. pylori IgG seropositivity (0.35 vs 0.55 ng/mL, p = .3; 3267.4 ± 753.0 vs 2808.3 ± 911.4 pg/mL, p = .06; 470 ± 176 vs 521 ± 179 ng/mL, p = .32, respectively).

CONCLUSIONS

Children infected with H. pylori are prone to short stature. This effect seems to be independent of neuroendocrine hormones.

Prevalence and risk factors of Helicobacter pylori infection in asymptomatic Chinese children: a prospective, cross-sectional, population-based study

BACKGROUND

Limited research has been published on current Helicobacter pylori infection rate in asymptomatic children in China.

AIM

To assess current Helicobacter pylori infection rate, distribution characteristics and risk factors in Chinese asymptomatic children.

METHODS

A prospective, cross-sectional, population-based study was performed from 2009 to 2011 in three cities of China. Helicobacter pylori infection was diagnosed by a stool antigen test. Multi-stage cluster random sampling was used to select asymptomatic children including neonates. Socioeconomic details were obtained through a standardised questionnaire.

RESULTS

Among total of 3491 children (0-18 years), the global infection rate was 6.8% and there were no significant differences between genders. Age specific infection rate between regions was significantly different (P < 0.05). The infection rate significantly increased with age (P for trend <0.01). It was low during the newborn (0.6%) to preschool period and was significantly increased in high school students (13.5%) (P < 0.01). Multivariable regression indicated that hand sanitisation, individually served meals, higher education level of mother, above average living space and residence in urban areas were significantly protective against infection (OR 0.749, 0.698, 0.720, 0.838 and 0.770 respectively). Conversely, consuming meals in unsanitised conditions, sharing towels, receiving pre-chewed food from the mother, artificial feeding and family history of gastrointestinal disease were significantly associated with the risk of infection (OR 1.200, 1.965, 2.002, 1.071 and 2.093 respectively).

CONCLUSIONS

Helicobacter pylori infection rate increases with age in Chinese asymptomatic children and is common after 10 years of age. The rate of infection is related to socioeconomic status.

Kyoto global consensus report on Helicobacter pylori gastritis

OBJECTIVE

To present results of the Kyoto Global Consensus Meeting, which was convened to develop global consensus on (1) classification of chronic gastritis and duodenitis, (2) clinical distinction of dyspepsia caused by Helicobacter pylori from functional dyspepsia, (3) appropriate diagnostic assessment of gastritis and (4) when, whom and how to treat H. pylori gastritis.

DESIGN

Twenty-three clinical questions addressing the above-mentioned four domains were drafted for which expert panels were asked to formulate relevant statements. A Delphi method using an anonymous electronic system was adopted to develop the consensus, the level of which was predefined as ≥80%. Final modifications of clinical questions and consensus were achieved at the face-to-face meeting in Kyoto.

RESULTS

All 24 statements for 22 clinical questions after extensive modifications and omission of one clinical question were achieved with a consensus level of >80%. To better organise classification of gastritis and duodenitis based on aetiology, a new classification of gastritis and duodenitis is recommended for the 11th international classification. A new category of H. pylori-associated dyspepsia together with a diagnostic algorithm was proposed. The adoption of grading systems for gastric cancer risk stratification, and modern image-enhancing endoscopy for the diagnosis of gastritis, were recommended. Treatment to eradicate H. pylori infection before preneoplastic changes develop, if feasible, was recommended to minimise the risk of more serious complications of the infection.

CONCLUSIONS

A global consensus for gastritis was developed for the first time, which will be the basis for an international classification system and for further research on the subject.

Prevalence of Helicobacter pylori in children in eastern Turkey and molecular typing of isolates

The objectives of the present study were to determine Helicobacter pylori via culture, polymerase chain reaction and histopathological diagnosis in 101 children ranging in age from 4 to 18 years, to identify the association among restriction fragment length polymorphism types and clinical disease and to investigate the relationships among different isolates of H. pylori in different age groups. We observed a high prevalence of H. pylori infections in children between the ages of 13 and 18 (75.8%), while children aged 4 to 6 years had the lowest prevalence of infection (40%). H. pylori was detected in 30.7% (31 of 101), 66.3% (67 of 101) and 63.2% (60 of 95) of children as determined by culture methods, PCR and histological examination, respectively. H. pylori isolates with RFLP types I and III were the most common among children with antral nodularity, whereas RFLP types II and IV were the least detected types. Interestingly, all isolates from peptic ulcer patients were type III. Although our results show a high prevalence of H. pylori infections in the pediatric population in eastern Turkey, no association was identified between H. pylori infection with antral nodularity and recurring abdominal pain. In addition, we found low genetic variation among H. pylori isolates from children and no association between RFLP types and antral nodularity (p > 0.05). Additionally, we found that H. pylori isolates with specific RFLP types were predominant in different age groups.

Accuracy of stool antigen test for the diagnosis of Helicobacter pylori infection in children: a meta-analysis

INTRODUCTION

Helicobacter pylori (H. pylori) is regarded as a major pathogen in gastrointestinal diseases and the infection rate is still at a high level in children. Therefore, the diagnosis is of great clinical importance. The objective was to perform a meta-analysis on H. pylori stool antigen test (SAT) for the diagnosis of the infection in children.

METHODS

Published information on the sensitivity and specificity of stool antigen test in each study was collected to assess the accuracy of the test for the diagnosis of H. pylori infection. Forty-five eligible studies were selected for analysis. Data on the publication year, H. pylori prevalence, eradication rate and gold standard of each study were summarized.

RESULT

Forty-five studies, including 5931 patients, evaluated the accurancy of H. pylori SAT. Pooled sensitivity, specificity, LR+ and LR- were: 92.1%, 94.1%, 17.01, 0.085, respectively. Subgroup analyses were conducted to evaluate the sensitivity and specificity of H. pylori SAT in different situations and found that sensitivity and specificity were significantly higher when monoclonal H. pylori SAT and two or more reference methods were used.

CONCLUSIONS

Detection of H. pylori antigen in stools with ELISA monoclonal antibodies is a non-invasive efficient test for the diagnosis of infection in children. However, the available one-step and polyclonal SAT tests are still unreliable.

Helicobacter pylori infection - recent developments in diagnosis

Considering the recommended indications for Helicobacter pylori (H. pylori) eradication therapy and the broad spectrum of available diagnostic methods, a reliable diagnosis is mandatory both before and after eradication therapy. Only highly accurate tests should be used in clinical practice, and the sensitivity and specificity of an adequate test should exceed 90%. The choice of tests should take into account clinical circumstances, the likelihood ratio of positive and negative tests, the cost-effectiveness of the testing strategy and the availability of the tests. This review concerns some of the most recent developments in diagnostic methods of H. pylori infection, namely the contribution of novel endoscopic evaluation methodologies for the diagnosis of H. pylori infection, such as magnifying endoscopy techniques and chromoendoscopy. In addition, the diagnostic contribution of histology and the urea breath test was explored recently in specific clinical settings and patient groups. Recent studies recommend enhancing the number of biopsy fragments for the rapid urease test. Bacterial culture from the gastric biopsy is the gold standard technique, and is recommended for antibiotic susceptibility test. Serology is used for initial screening and the stool antigen test is particularly used when the urea breath test is not available, while molecular methods have gained attention mostly for detecting antibiotic resistance.

Stool antigen tests for the management of Helicobacter pylori infection

Stool antigen tests (SATs) are noninvasive diagnostic modules for Helicobacter pylori (H. pylori) infection. Two types of SATs exist for the diagnosis of H. pylori infection, one based on enzyme immunoassay (EIA) and another on immunochromatography (ICA). SATs do not require expensive chemical agents or specified equipment; hence, they are less expensive compared with the urea breath test. Both European and Japanese guidelines have shown that EIA-based SATs using monoclonal antibodies are useful for primary diagnosis as well as for the assessment of eradication therapy. ICA-based tests do not require particular equipment and are therefore useful in developing countries. SATs are also useful for the diagnosis of H. pylori infection in children and post gastric surgery patients. SATs performed via EIA can assess H. pylori infection in a large number of subjects, almost as well as serology. Thus, SATs would be useful or detecting current infection in such a survey to identify and eradicate H. pylori infection. The accuracy of SATs is lower when the stool samples are unformed or watery, because H. pylori-specific antigens in the stool samples are diluted. Temperature and the interval between stool sample collection and measurement also affect the results of SATs. The choice of test kit depends on the sensitivity and specificity in each region and the circumstances of each patient.

Clinical practice: Helicobacter pylori infection in childhood

Helicobacter pylori infection is recognised as a cause of gastritis and peptic ulcer disease (PUD) and usually acquired during the first years of life. While there is a decline in the prevalence of H. pylori infection in northern and western European countries, the infection is still common in southern and eastern parts of Europe and Asia. Symptoms of H. pylori-related PUD are nonspecific in children and may include epigastric pain, nausea and/or vomiting, anorexia, iron deficiency anaemia and hematemesis. Besides, only a small proportion of children develop symptoms and clinically relevant gastrointestinal disease. H. pylori infection can be diagnosed either by invasive tests requiring endoscopy and biopsy or non-invasive tests including the (13)C-urea breath test, detection of H. pylori antigen in stool and detection of antibodies in serum, urine and saliva. The aim of treatment is at least 90 % eradication rate of the bacteria, and a combination of two antibiotics plus a proton pump inhibitor has been recommended as first-line treatment. However, frequent use of antibiotics during childhood is associated with a decline in eradication rates and the search for new treatment strategies as well. This is an overview of the latest knowledge and evidence-based guidelines regarding clinical presentation, diagnosis and treatment of H. pylori infection in childhood.

Helicobacter pylori infection in infants and toddlers in South America: concordance between [13C]urea breath test and monoclonal H. pylori stool antigen test

Accurate noninvasive tests for diagnosing Helicobacter pylori infection in very young children are strongly required. We investigated the agreement between the [(13)C]urea breath test ([(13)C]UBT) and a monoclonal ELISA (HpSA) for detection of H. pylori antigen in stool. From October 2007 to July 2011, we enrolled 414 infants (123 from Brazil and 291 from Peru) of ages 6 to 30 months. Breath and stool samples were obtained at intervals of at least 3 months from Brazilian (n = 415) and Peruvian (n = 908) infants. [(13)C]UBT and stool test results concurred with each other in 1,255 (94.86%) cases (kappa coefficient = 0.90; 95% confidence interval [CI] = 0.87 to 0.92). In the H. pylori-positive group, delta-over-baseline (DOB) and optical density (OD) values were positively correlated (r = 0.62; P < 0.001). The positivity of the tests was higher (P < 0.001; odds ratio [OR] = 6.01; 95% CI = 4.50 to 8.04) in Peru (546/878; 62.2%) than in Brazil (81/377; 21.5%) and increased with increasing age in Brazil (P = 0.02), whereas in Peru it decreased with increasing age (P < 0.001). The disagreement between the test results was associated with birth in Brazil and female gender but not with age and diarrhea. Our results suggest that both [(13)C]UBT and the stool monoclonal test are reliable for diagnosing H. pylori infection in very young children, which will facilitate robust epidemiological studies in infants and toddlers.

Helicobacter pylori virulence genes detected by string PCR in children from an urban community in northeastern Brazil

The accuracy of a nested PCR in gastric DNA obtained by a string test for the diagnosis of Helicobacter pylori infection in asymptomatic children was 94.0%. The cagA-positive toxigenic vacAs1m1 strains were the most prevalent strains, indicating that this population is colonized early by the strains associated with gastric cancer.

Comparison of sequential and standard therapy for Helicobacter pylori eradication in children and investigation of clarithromycin resistance

AIMS

The aim of the present study was to compare the efficacy of sequential and standard triple-drug regimen for Helicobacter pylori (H pylori) eradication in children and to determine the primary resistance rate to clarithromycin.

METHODS

Children with H pylori infection randomized to receive either standard regimen (n = 28) consisting of lansoprazole for 30 days, amoxicillin and clarithromycin for 14 days or sequential regimen (n = 16) consisting of lansoprazole for 30 days, amoxicillin for 7 days, followed by clarithromycin and metronidazole for the next 7 days. Clarithromycin susceptibility of H pylori was assessed with fluorescence in-situ hybridization technique. Eradication was controlled by C urea breath test or monoclonal stool antigen test 4 weeks after the end of the therapy.

RESULTS

H pylori eradication rate was higher in the sequential therapy group (93.7%), compared with the standard therapy group (46.4%) (P = 0.002). There was no difference in adverse drug reactions and in compliance to the treatment between the groups. Primary clarithromycin resistance rate for H pylori was found as 25.7% (n = 9). All of the patients having clarithromycin resistance were coincidentally in the standard therapy group. After the exclusion of these 9 patients, sequential therapy was again found to be more effective than the standard therapy (P = 0.02).

CONCLUSIONS

Sequential therapy seems highly effective for eradicating H pylori in children; however, the difference between 2 groups in resistant strains was the limitation of the study. Our country needs to reassess the effectiveness of standard triple therapy regimen for H pylori eradication.

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

BACKGROUND/AIM

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Effect of Helicobacter pylori infection on iron absorption in asymptomatic adults consuming wheat flour fortified with iron and zinc

Helicobacter pylori infection could impair iron absorption from fortified products. The objective of the study was to determine the effect of H. pylori infection on iron absorption from asymptomatic adults consuming wheat flour fortified with iron and zinc. The (13)C urea breath test was used to assess H. pylori infection. Twenty-four H. pylori-positive and 26 H. pylori-negative volunteers completed the study. On day 1, the subjects were randomized to receive for breakfast bread fortified with either ferrous sulfate and zinc sulfate or ferrous fumarate and zinc oxide. Bread fortified with ferrous sulfate was labeled with (59)Fe as sulfate, and bread fortified with ferrous fumarate was labeled with (55)Fe as fumarate. On day 3, they received the other type of bread, with the respective tracers. On days 18-23, a proton pump inhibitor was administered to all subjects. On day 24, all subjects received bread fortified with ferrous fumarate and zinc oxide labeled with (55)Fe as fumarate. H. pylori prevalence was 77.6%. The geometric mean (±1 SD) of iron absorption was significantly higher for ferrous sulfate than fumarate (6.9 ± 2.9% vs. 0.5 ± 3.5%, p < 0.001). The H. pylori-negative subjects absorbed significantly more iron from bread fortified with either ferrous sulfate (10.5 ± 3.1% vs. 4.4 ± 2.2%, p < 0.001) or ferrous fumarate (0.6 ± 3.9% vs. 0.4 ± 3.1%, p < 0.001). Iron absorption was not significantly different between groups after administration of a proton pump inhibitor (0.3 ± 3.3% vs. 0.3 ± 2.7%, p = 0.11). H. pylori infection has a negative effect on iron absorption in asymptomatic adults consuming iron- and zinc-fortified wheat flour.

13C-urea breath test for the diagnosis of Helicobacter pylori infection in children: a systematic review and meta-analysis

BACKGROUND

The (13) C-urea breath test ((13) C-UBT) is a safe, noninvasive and reliable method for diagnosing H. pylori infection in adults. However, the test has shown variable accuracy in the pediatric population, especially in young children. We aimed to carry out a systematic review and meta-analysis to evaluate the performance of the (13) C-UBT diagnostic test for H. pylori infection in children.

METHODS

We conducted a systematic review of the PubMed, Embase and Liliacs databases including studies from January 1998 to May 2009. Selection criteria included studies with at least 30 children and reporting the comparison of (13) C-UBT against a gold standard for H. pylori diagnosis. Thirty-one articles and 135 studies were included for analysis. Children were stratified in subgroups of <6 and ≥6 years of age, and we considered variables such as type of meal, cutoff value, tracer dose, and delta time for the analysis.

DISCUSSION

The (13) C-UBT performance meta-analyses showed 1, good accuracy in all ages combined (sensitivity 95.9%, specificity 95.7%, LR+ 17.4, LR- 0.06, diagnostic odds ratio (DOR) 424.9), 2, high accuracy in children >6 years (sensitivity 96.6%, specificity 97.7%, LR+ 42.6, LR- 0.04, DOR 1042.7), 3, greater variability in accuracy estimates and on average a few percentage points lower, particularly specificity, in children ≤6 years (sensitivity 95%, specificity 93.5%, LR+ 11.7, LR- 0.12, DOR 224.8). Therefore, the meta-analysis shows that the (13) C-UBT test is less accurate for the diagnosis of H. pylori infection in young children, but adjusting cutoff value, pretest meal, and urea dose, this accuracy can be improved.

Evidence-based guidelines from ESPGHAN and NASPGHAN for Helicobacter pylori infection in children

OBJECTIVE

As the clinical implications of Helicobacter pylori infection in children and adolescents continue to evolve, ESPGHAN and NASPGHAN jointly renewed clinical guidelines using a standardized evidence-based approach to develop updated recommendations for children and adolescents in North America and Europe.

METHODS

An international panel of 11 pediatric gastroenterologists, 2 epidemiologists, 1 microbiologist, and 1 pathologist was selected by societies that developed evidence-based guidelines based on the Delphi process with anonymous voting in a final face-to-face meeting. A systematic literature search was performed on 8 databases of relevance including publications from January 2000 to December 2009. After excluding nonrelevant publications, tables of evidence were constructed for different focus areas according to the Oxford classification. Statements and recommendations were formulated in the following areas: whom to test, how to test, whom to treat, and how to treat. Grades of evidence were assigned to each recommendation based on the GRADE system.

RESULTS

A total of 2290 publications were identified, from which 738 were finally reviewed. A total of 21 recommendations were generated, and an algorithm was proposed by the joint committee providing evidence-based guidelines on the diagnostic workup and treatment of children with H pylori infection.

CONCLUSIONS

These clinical practice guidelines represent updated, best-available evidence and are meant for children and adolescents living in Europe and North America, but they may not apply to those living on other continents, particularly in developing countries with a high H pylori infection rate and limited health care resources.

Utility of stool sample-based tests for the diagnosis of Helicobacter pylori infection in children

OBJECTIVE

Helicobacter pylori antigen or DNA in stool are meant to detect the bacteria; however, in children the colonization of the gastric mucosa by H pylori is usually weak and fecal excretion of antigen or DNA varies considerably, challenging the utility of these tests in this age group. The aim of the present study was to carry out a systematic review and meta-analysis to evaluate the performance of stool H pylori DNA and antigen tests for the diagnosis of infection in children.

METHODS

We conducted a systematic review and meta-analysis to assess the accuracy of stool tests for diagnosis of H pylori infection in children. We searched PubMed, EMBASE, and LILACS databases. Selection criteria included participation of at least 30 children and the use of a criterion standard for H pylori diagnosis. In a comprehensive search, we identified 48 studies.

RESULTS

Regarding antigen-detection tests, enzyme-linked immunosorbent assay (ELISA) monoclonal antibodies showed the best performance, with sensitivity and specificity of 97%, positive likelihood ratio (LR+) of 29.9, and negative likelihood ratio (LR-) of 0.03. ELISA polyclonal antibodies had sensitivity of 92%, specificity of 93%, LR+ of 16.2, LR- of 0.09, and high heterogeneity (P < 0.0001). One-step monoclonal antibody tests demonstrated sensitivity of 88%, specificity of 93%, LR+ of 10.6, and LR- of 0.11. For DNA detection, polymerase chain reaction-based test showed sensitivity of 80.8%, specificity of 98%, LR+ of 17.1, and LR- of 0.18.

CONCLUSIONS

Detection of H pylori antigen in stools with ELISA monoclonal antibodies is a noninvasive efficient test for diagnosis of infection in children. One-step tests showed low accuracy and more studies are needed to obtain a useful office-based screening test. The available molecular tests are still unreliable.

The effect of Helicobacter pylori and economic status on growth parameters and leptin, ghrelin, and insulin-like growth factor (IGF)-I concentrations in children

BACKGROUND

It was suggested that gastric colonization with Helicobacter pylori (H. pylori) was associated with suboptimal nutrition and growth in childhood. Furthermore, several studies indicated a relationship between H. pylori colonization and alterations in the circulating levels of growth-related molecules (GRM). Accordingly, in this study, we investigate the effect of H. pylori infection on GRMs and on the growth of healthy school children, taking into consideration the effect of their economic status (ES) and anthropometric indices of their parents.

METHODS

To acquire sociodemographic and anthropometric nutritional parameters and to detect H. pylori-specific serum IgG antibodies and growth-related molecules, we evaluated a total of 473 children attending four different primary and secondary schools in Istanbul. Subsequently, we assessed the effect of H. pylori on growth-related parameters (weight for age SDS, height for age SDS, BMI SDS, TSF, and waist-to-hip ratio) and on GRMs (leptin, ghrelin, and insulin-like growth factor-1 (IGF-1)), controlling for age, gender, family income, household crowding (HC), breastfeeding, maternal and paternal BMI SDS, and midparental height SDS with complex statistical models.

RESULTS

Of the 473 children (275 F/198 M, age 6-15 years; mean: 10.3 ± 0.1 years), 161 (34%) were H. pylori-positive. The prevalence of H. pylori was significantly higher in lower economic status (ES) groups, in children living in crowded houses, and in older age groups. Using simple statistical models, we did not find any significant associations between H. pylori infection and the growth parameters. However, in complex models for height for age SDS and for weight for age SDS, there was a significant interaction between H. pylori infection status and ES. Whereas in H. pylori-positive subjects, mid-income family children were both taller and heavier than the low-income group, there was no such an association in H. pylori-negative subjects. Among biochemical parameters, only ghrelin levels were associated with H. pylori infection in all models. Leptin levels were associated with HC in girls, whereas none of the parameters was significantly associated with leptin levels in boys. For IGF-1 levels, for boys, age and maternal BMI, and for girls, age and HC were significantly associated with IGF-1 levels.

CONCLUSION

We suggest that H. pylori may impair growth significantly only in susceptible children where unfavorable socioeconomic conditions facilitate its action, probably through mechanisms, at least in part, involving growth-related molecules.

The survey of Helicobacter pylori infection in infant

This present study was designed to determine the prevalence of H. pylori in infants and correlation of this infection with age. In a prospective descriptive study in Tabriz children hospital, we conducted analysis of children within age 2 year or younger who had H. pylori infection that were diagnosed with endoscopies and biopsy. Prevalence of infection was higher in the infants whose mothers had a low education level (p = 0.045). The H. pylori prevalence didn't differ between exclusively breastfeeding to six months and infants who had never breast fed (26.6% vs. 13.3%) (p = 0.2). We could not find any correlation between rate of infection and age of patients which used by regression model for analysis and t test (p = 0.5). Based on our study the prevalence of H. pylori infection in infants living in North West of Iran was low. We could not find any correlation between rate of infection and age of patients.

Impact of H. pylori on growth: is the infection or mucosal disease related to growth impairment?

BACKGROUND

Helicobacter pylori (H. pylori) has been recognized as one of the most common chronic bacterial infections in the world. Most children are colonized in early childhood, and the infection will last a lifetime unless the child is treated with appropriate antibiotics.

AIM

To evaluate whether H. pylori infection has an influence on growth and whether the severity of endoscopic findings relates to the growth impairment.

METHODS

We formed four groups based on the presence or absence of H. pylori infection and gastrointestinal complaints as follows: group I: RAP +/H. pylori+; group II: RAP +/H. pylori-; group III: RAP -/H. pylori+; group IV: RAP -/H. pylori-. The relationship between endoscopic appearances, histological severity of gastritis, and antral H. pylori density with growth parameters was evaluated.

RESULTS

The BMI standard derivation scores of groups I and II were significantly lower than those of asymptomatic controls independent of their H. pylori status. A significant difference in height for age standard derivation scores was observed only between groups I and IV. When we compared the BMI and height for age standard derivation scores of group III and group IV combined with that of the endoscopically normal children in the recurrent abdominal pain group, there was no significant difference between the two groups.

CONCLUSION

Recurrent abdominal pain associated with gastric mucosal injury plays a role in a decrease in BMI independent of H. pylori infection. However, if recurrent abdominal pain originates from H. pylori infection, it appears that linear growth is also affected.

Exposure to antibiotics in a United States-Mexico border birth cohort

OBJECTIVE

The goal was to compare the frequency of children's antibiotic intake, emphasizing antibiotics with anti-Helicobacter pylori effects, in El Paso, Texas, and Juarez, Mexico.

METHODS

Hispanic children were enrolled prenatally at mother-child clinics in El Paso, and Juarez, in 1998-2000, to identify determinants of H pylori infection. During follow-up examinations targeted every 6 months from 6 to 84 months of age, caretakers reported medication use during the preceding interval. Courses of any systemic and H pylori-effective antibiotics were compared for US and Mexican children.

RESULTS

Antibiotic data were available for 602 children, from 2938 follow-up visits. Overall antibiotic intake was higher in Juarez, where 84% of children received > or = 1 course during the follow-up period (52% of visits), compared with El Paso, where 76% of children received > or = 1 course (40% of visits). In contrast, the intake of H pylori-effective antibiotics was higher in El Paso, where 65% of children received > or = 1 course during the follow-up period (27% of visits), compared with Juarez, where 44% of children received > or = 1 course (16% of visits). Of H pylori-effective courses, 94% contained amoxicillin and 2% each clarithromycin, metronidazole, and furazolidone; uses were primarily for throat and ear infections, diarrhea, and cold/flu.

CONCLUSIONS

Pediatric antibiotic use was higher in Mexico than on the US side of the border. Apparent misuse of H pylori-effective antibiotics was more frequent in Juarez but also occurred in El Paso. Such misuse of antibiotics may lead to drug resistance and may impair the control of H pylori infection in this region.

Endoscopic tests for the diagnosis of Helicobacter pylori infection in children: Validation of rapid urease test

BACKGROUND

Rapid urease test (CLO-test) is an inexpensive and quick method for diagnosis of Helicobacter pylori infection with controversial results in children. We evaluated the performance of CLO-test in relation to endoscopic and histological findings in children with H. pylori infection.

MATERIALS AND METHODS

We studied the medical records of children with H. pylori infection who were diagnosed between 1989 and 2009. Noninfected children were used as controls. H. pylori infection was defined by positive culture or by two other positive tests (histology and CLO-test, or urea breath test when a single test was positive). All children had histology together with CLO-test. Tissue culture was performed whenever possible.

RESULTS

Five hundred thirty infected children (10.4 +/- 3.0 years) and 1060 controls (7.3 +/- 4.4 years) were studied. Sensitivity of CLO-test was 83.4% (95% CI, 79.9-86.3%), of culture 84.6% (95% CI, 78.7-89.1%), of histology 93.2% (95% CI, 90.7-95.1%), and specificity 99% (95% CI, 98.2-99.4%), 100%, and 100% respectively. CLO-test positivity was correlated with higher bacterial density (p < .001), activity (p < .001) and severity of gastritis (p < .01), older age (p < .01), and the presence of antral nodularity (p < .001). When CLO-test was positive, the concordance with histology and culture was high (95.5 and 89.2% respectively), whereas low concordance was observed when CLO-test was negative (17.05 and 45.83% respectively).

CONCLUSIONS

CLO-test had lower sensitivity and comparable specificity with histology. Both tests should be performed concurrently to accurately diagnose H. pylori infection in children.

Prevalence of Helicobacter pylori infection in high-school students on Lanyu Island, Taiwan: risk factor analysis and effect on growth

BACKGROUND/PURPOSE

The Yami inhabit Lanyu Island and are the smallest and most primitive aboriginal tribe in Taiwan. Lanyu Island is a closed environment and little information is available on the prevalence of Helicobacter pylori infection there. This study aimed to establish the prevalence of H. pylori infection in high-school students on Lanyu Island and its risk factors and effect on growth.

METHODS

A cross-sectional population-based study was conducted among high-school students to determine the prevalence of H. pylori infection by using the 13C urea breath test. A questionnaire was administered to the recruited population. Relevant personal and socioeconomic data for risk factors of infection were collected. Body height and weight of the recruited adolescents in relation to H. pylori infection were analyzed.

RESULTS

A total of 106 high-school students (55 boys and 51 girls), with a mean age of 14.3 +/- 1.4 years were enrolled. The overall prevalence of H. pylori infection was 54.7%. Those residing in Dongcing village had the highest rate of H. pylori infection (73.3%). There was no difference in the prevalence of H. pylori infection according to sex, ethnicity, socioeconomic level or parental education. Sixty-two students (54.8%) were completely asymptomatic and the others had at least one gastrointestinal symptom. H. pylori infection was asymptomatic in 56.8% and symptomatic in 53.2% of students. There was no significant difference between infected and uninfected children with regard to body weight, height and body mass index.

CONCLUSION

The prevalence of H. pylori infection is high among high-school students on Lanyu Island. There is no evidence that infection is related to growth failure.

Helicobacter pylori diagnostic tests in children: review of the literature from 1999 to 2009

The array of tests that can be used for diagnosis of Helicobacter pylori infection is large, and it can be confusing to define which test to use particularly in children where results may not be comparable to those obtained in adult patients. Using PubMed, we reviewed the English literature from January 1999 to May 2009 to identify articles that determined sensitivity and specificity of H. pylori invasive and non-invasive diagnostic tests in children. We excluded articles that presented a review of the literature, abstracts, case reports, or series where children's results could not be separated from adult populations. Of the tissue based methods, rapid urease tests have better sensitivity than histology to detect presence of H. pylori; however, histology can detect the pathology associated with disease including gastritis, intestinal metaplasia, and other conditions that could be the cause of the child's symptoms. Culture of gastric tissues or stool has 100% specificity but sensitivity is low. Of the serologic tests, immunoblot has the best sensitivity. The urea breath tests have >75% sensitivity for detection of H. pylori before and after treatment. Immunoassays in stool using monoclonal antibodies have >95% sensitivity for detection of H. pylori before and after treatment. PCR testing can be performed in tissue and stool samples and can detect genes associated to antibiotic resistance. In summary, the current commercial non-invasive tests have adequate sensitivity and specificity for detecting the presence of H. pylori; however, endoscopy with histopathology is the only method that can detect H. pylori and lesions associated with the infection.

Improved performance of a rapid office-based stool test for detection of Helicobacter pylori in children before and after therapy

A modified version of a rapid office based one-step monoclonal immunoassay for detection of Helicobacter pylori antigen in stool samples from children was evaluated against biopsy specimen-based methods and compared to a monoclonal enzyme immunoassay using the same antigen. Blinded stool samples from 185 children (0.3 to 18.2 years) were investigated at the time of upper endoscopy prior to anti-H. pylori therapy; 62 children were H. pylori infected and 123 noninfected according to predefined reference standards. Samples obtained 6 to 8 weeks after anti-H. pylori therapy were available from 58 children (3.8 to 17.7 years) and were compared to results of the [(13)C]urea breath test (14/58 were positive). The rapid stool tests were performed by two independent readers. Of 243 rapid tests performed, 1 (0.4%) was invalid for technical reasons. Equivocal results (very weak line) were reported 16 times by reader 1 and 27 times by reader 2. When equivocal results were considered positive, the two observers agreed on 76 positive and 160 negative results and disagreed on 7 samples (2.9%). The sensitivity was 90.8% for reader 1 and 85.5% for reader 2, and the specificity was 91.0% and 93.4%, respectively. The monoclonal enzyme immunoassay revealed a sensitivity and specificity of 94.7% and 97.6%, respectively. The modified chromatographic immunoassay is a good alternative in settings or situations when the monoclonal enzyme immunoassay or the [(13)C]urea breath test are not available or feasible. In order to improve sensitivity, very weak lines should be considered positive test results.

Urea breath test in children: the United States prospective, multicenter study

BACKGROUND

The urea breath test (UBT) is generally considered the gold standard for the diagnosis of Helicobacter pylori infections in adults.

GOALS

To investigate the utility and accuracy of urea breath testing in children from the United States.

METHODS

Children scheduled to undergo upper gastrointestinal endoscopy for various clinical symptoms underwent a 13C-UBT using the US standard protocol for adults. Results were compared with rapid urease testing (RUT), culture, and histology. H. pylori positivity was defined according to the FDA, Division of Anti-Infective Drug Products criteria, i.e. positive culture and/or positive RUT and histology. H. pylori negativity was defined as all tests negative. Results were evaluated by delta over baseline (DOB) and urea hydrolysis rate (UHR).

RESULTS

A total of 176 children from five centers were evaluated; 48 were infected. Compared to the defined standard, the results with the UBT based on delta over baseline (DOB) cut-off value (positive: > or = 2.4 per thousand) showed that the sensitivity and specificity of the UBT were 97.9% and 96.1%, respectively. Based on the UHR cut-off value (positive: > or = 10.0 microg/min), the sensitivity and specificity were 95.8% and 99.2%. In young children (2- to 5-year olds), sensitivity and specificity of UHR method were higher than the DOB method (100% and 100% vs 100% and 82.4%, respectively).

CONCLUSION

The US standard (13)C-UBT proved to be both simple and accurate for the diagnosis of H. pylori infections in children. The UHR method to calculate of (13)C-UBT result provided excellent results for children of all ages.

Helicobacter pylori infection in children

Helicobacter pylori infection is a common problem in pediatric practice, and its acquisition is related with poor socioeconomic conditions. Although the organism is thought to be responsible for many diseases, only a handful of them have a direct causal relationship. At present, only a small number of children with well-defined clinical syndromes are benefited from testing and treatment. The treatment should include at least two antibiotics with a proton pump inhibitor.

Helicobacter pylori infection in young children detected by a monoclonal stool antigen immunoassay

The prevalence of Helicobacter pylori infection in young children attending day care facilities was studied using a monoclonal stool antigen test. Of 316 samples, 78 (24.7%) were positive. Only 7/98 (7.1%) of the 3- to 12-month-old infants tested positive compared with 71/218 (32.5%) of the 13- to 60-month-old group. We conclude that approximately 30% of infants may become infected with H. pylori after the first year of life.

The interaction between Helicobacter pylori and atopy: does inverse association really exist?

AIM

To date, cross-sectional and case-control studies suggest an inverse association between Helicobacter pylori infection and atopic diseases, whereas the immunologic basis has not been studied yet. In this study we investigated T helper (Th) cell function in H. pylori-infected children and compared cytokine responses in atopic and non-atopic groups.

METHODS

The study groups was recruited from a cohort of 327 healthy children evaluated and followed-up for 6 years to assess the natural history of H. pylori infection. Seventy-four of 136 healthy children who underwent (13)C urea breath test were eligible and accepted to participate. All participants were evaluated by a questionnaire, and skin-prick testing. According to the results, children were divided into four groups with respect to the presence or absence of H. pylori and atopy. Peripheral blood mononuclear cells isolated from 34 of 74 children were cultured with H. pylori, Der p 1, and phytohemagglutinin (PHA). Interferon-gamma (IFN-gamma), interleukin (IL)-4 and IL-10, transforming growth factor-beta (TGF-beta) levels were measured in supernatants.

RESULTS

The frequency of atopy was lower in H. pylori-infected group (31.9% vs. 48.1, p = .22), while atopic symptoms were similar between infected and non-infected children. While PHA and H. pylori induced IFN-gamma levels were significantly higher in H. pylori-infected children, concomitant presence of both atopy and H. pylori decreased the level of PHA and H. pylori induced IFN-gamma production. PHA and Der p 1-induced IL-4 levels were higher in atopic children, and IL-4 production was suppressed when they were concomitantly infected with H. pylori. The production of TGF-beta was found to be suppressed in atopic children irrespective of the presence of H. pylori infection.

CONCLUSION

The results of the current study demonstrated a counteractive Th1 and Th2 cytokine interaction between H. pylori infection and atopy. However, this counteractive immunologic balance did not protect against atopy.

Antibody-based detection tests for the diagnosis of Helicobacter pylori infection in children: a meta-analysis

Background

Numerous serologic tests are available for the diagnosis of H. pylori infection in children. Common designs of antibody-based detection tests are ELISA and Western Blot (WB). For developing countries with limited laboratory resources and access, ELISA would be the preferred method because of its simplicity, lower cost and speed. Although in adults ELISA has proven to be highly accurate in diagnosing H. pylori infection; in children, it has shown variable accuracy.

Methods/Findings

We conducted a systematic review and meta-analysis to assess the accuracy of antibody-based detection tests for the diagnosis of H. pylori infection in children. Selection criteria included participation of at least 30 children and the use of a gold standard for H. pylori diagnosis. In a comprehensive search we identified 68 studies. Subgroup analyses were carried out by technique, immunoglobulin class, and source of test (commercial and in-house). The results demonstrated: 1) WB tests showed high overall performance, sensitivity 91.3% (95% CI, 88.9–93.3), specificity 89% (95% CI, 85.7–91.9), LR+ 8.2 (95% CI, 5.1–13.3), LR− 0.06 (95% CI, 0.02–0.16), DOR 158.8 (95% CI, 57.8–435.8); 2) ELISA-IgG assays showed low sensitivity 79.2% (95% CI, 77.3–81.0) and high specificity (92.4%, 95% CI, 91.6–93.3); 3) ELISA commercial tests varied widely in performance (test for heterogeneity p<0.0001); and 4) In-house ELISA with whole-cell antigen tests showed the highest overall performance: sensitivity 94% (95% CI, 90.2–96.7), specificity 96.4% (95% CI, 94.2–97.9), LR+ 19.9 (95% CI, 7.9–49.8), LR− 0.08 (95% CI, 0.04–0.15) DOR 292.8 (95% CI, 101.8–841.7).

Conclusions/Significance

WB test and in-house ELISA with whole-cell antigen tests are the most reliable tests for the diagnosis of H. pylori infection in children. Antigens obtained from local strains of the community could partially explain the good overall accuracy of the in-house ELISA. Because of its cost and technical demands, in-house ELISA might be more suitable for use in developing countries.