Helicobacter pylori infection and extragastric disorders in children: A critical update

Impact of Helicobacter pylori Infection upon the Evolution and Outcome of Pediatric Immune Thrombocytopenic Purpura: A Comprehensive Review

In adults with immune thrombocytopenic purpura (ITP), the identification of H. pylori infection and its subsequent eradication proved to aid platelet recovery. Similar findings, at a smaller scale, were allegedly reported by some pediatric studies. This review's objective was to establish the influence of H. pylori infection and its eradication upon platelet count and recovery in pediatric ITP. Three databases, namely Pubmed, Scopus and Web of Science, were searched for pediatric studies which investigated a link between H. pylori infection and thrombocytopenia. The search results retrieved a number of 21 articles which complied to the inclusion and exclusion criteria. Some studies report lower platelet values among children with ITP and documented H. pylori infection, as well as an improve in platelet numbers after H. pylori treatment. However, results are controversial, as multiple authors failed to identify a higher prevalence of H. pylori among children with ITP or a lack of significant change in therapeutic outcome with the addition of an eradication regimen to standard treatment. The main limitations of current pediatric studies remain the small study samples and the short follow-up periods of the included subjects. Hence, the long-term impact of H. pylori in children with ITP is still uncertain.

Helicobacter pylori Infections in Children

In the context of epidemiology, host response, disease presentation, diagnosis, and treatment management, the manifestation of Helicobacter pylori (H. pylori) infection diverges between children and adults. H. pylori infection stands out as one of the most prevalent bacterial infections globally, and its prevalence in both children and adults is decreasing in many developing countries but some still struggle with a high prevalence of pediatric H. pylori infection and its consequences. The majority of infected children are asymptomatic and pediatric studies do not support the involvement of H. pylori in functional disorders such as recurrent abdominal pain. The pathophysiology of H. pylori infection relies on complex bacterial virulence mechanisms and their interaction with the host immune system and environmental factors. This interaction gives rise to diverse gastritis phenotypes, which subsequently influence the potential development of various gastroduodenal pathologies. In clinical settings, the diagnosis of this infection in childhood requires an upper gastrointestinal endoscopic exam with mucosal biopsy samples for histology and culture, or Polymerase Chain Reaction (PCR) at the very least. When warranted, eradication treatment should be given when good compliance is expected, and there should be systematic use of a treatment adapted to the antimicrobial susceptibility profile. To combat the burgeoning threat of multidrug resistance, vigilant surveillance of resistance patterns and strategic antibiotic management are paramount.

Factors Associated With Helicobacter Pylori Infection Among School-Aged Children From a High Prevalence Area in Vietnam

Objectives: The study aimed to identify prevalence of H. pylori infection and associated risk factors among pupils of Ho Chi Minh city (HCMC). Methods: A total of 1,476 pupils aged 6-15 years were enrolled in this cross-sectional study using multiple-stage sampling method. Infection status was assessed using stool antigen-test. A questionnaire was used to obtain socio-demographic, behavioral, and environmental factors. Logistic regression was performed to assess possible factors related to the infection. Results: Of the 1,409 children included in the analysis, 49.2% were male and 95.8% were of Kinh ethnicity. About 43.5% of parents completed college or university. The overall prevalence of H. pylori was 87.7%. Infrequency of handwashing with soap after toilet, the use of only water to clean after toilet, crowded living areas, larger family size, and younger age were independently contributing to an increased prevalence of H. pylori. Conclusion: H. pylori infection is highly prevalent in HCMC, and is associated with poor hygienic practices, crowded living areas, larger family size, and younger age. These findings highlight the importance of fecal-oral route and the attribution of crowded living conditions to the spreading of H. pylori in HCMC. Therefore, preventive programs should be set up with a focus on education of hygiene practices, and oriented to those living in crowded conditions.

Is Helicobacter pylori Anyway Pathogen in Children?

Helicobacter pylori (H. pylori) infection is a continuous challenge for both gastroenterologists and pediatricians. The international guidelines regarding diagnostic and treatment pathways differ between adults and children. The pediatric guidelines are more restrictive because children are rarely affected by serious consequences, particularly in Western countries. Therefore, infected children should be treated only after a careful case-by-case evaluation by a pediatric gastroenterologist. In any case, recent studies are confirming an increasingly all-around pathological role of H. pylori even in asymptomatic children. For these reasons, following the current evidence, we feel that H. pylori-infected children could be treated starting in pre-adolescence, particularly in Eastern countries, because their stomachs have already begun to develop the biomarkers of gastric damage. Therefore, we believe that H. pylori is anyway pathogen in children. Nevertheless, the possible beneficial role of H. pylori in humans has not yet been conclusively disproved.

Association Between Helicobacter pylori Infection and Anemia Among Adult Dyspeptic Patients Attending Kiryandongo General Hospital, Uganda

Purpose

To determine the prevalence of anemia and its association with Helicobacter pylori infection among adult dyspeptic patients.

Patients and Methods

A cross-sectional study was conducted among 283 dyspeptic patients at Kiryandongo General Hospital, in Uganda. A structured questionnaire was administered to capture demographic and clinical characteristics of study participants. Four milliliters of blood were then collected into an EDTA vacutainer for Complete Blood Count (CBC) and analyzed using HUMA COUNT 30^TS, and peripheral blood smears were made and stained using Giemsa stain. Anemia was defined as hemoglobin levels <12g/dl in females and <13g/dl in men according to the World Health Organization (WHO). Helicobacter pylori (H. pylori) stool antigen test was performed using Whole power H. pylori Ag rapid test device, and saline stool preparation was examined for intestinal parasites. Chi-squared test and Logistic regression were performed to determine association, and a p-value of ≤0.05 was considered statistically significant.

Results

The overall prevalence of Helicobacter pylori infection was 42.4% (120/283). The prevalence of anemia among H. pylori-infected patients was 25.8% (31/120) and 15.3% (25/163) among H. pylori-negative counterparts. H. pylori infection was significantly associated with anemia (p-value 0.042), age (p-value 0.02, 0.009), water sources (p-value 0.0049,) and intestinal parasitic infestation (p-value 0.02), respectively.

Conclusion

This study has shown that the prevalence of H. pylori infection and anemia is high among dyspeptic patients at Kiryandongo General Hospital. H. pylori infection was found associated with anemia, age, water sources, and intestinal parasitic infestation. Routine screening of anemia in H. pylori-infected individuals and further studies to explore the relationship between anemia and H. pylori disease is highly recommended.

Detection of A2143G, A2142C, and A2142G Point Mutations with Real-Time PCR in Stool Specimens from Children Infected with Helicobacter pylori

Reports have indicated an increasing prevalence of clarithromycin resistance in children relative to adults. Thus, it is important to investigate primary clarithromycin resistance before therapy to avoid treatment failure. A2142G, A2143G, and A2142C point mutations in the peptidyltransferase region of the 23S ribosomal RNA (rRNA) of Helicobacter pylori (H. pylori) strains isolated from children with gastrointestinal symptoms and asymptomatic children were evaluated via real-time polymerase chain reaction (RT-PCR) using fecal DNA samples. The presence of H. pylori was determined using a fecal H. pylori antigen enzyme-linked immunosorbent assay (ELISA) kit from the stools of children (n = 543). A2143G, A2142C, and A2142G point mutations were detected via RT-PCR and confirmed by sequencing the 23S rDNA. Fecal H. pylori antigen testing was positive in 101 symptomatic (49) and asymptomatic (52) children. A significant difference was found between the 0–5- and 5–18-year-old groups in terms of the A2143G and A2142G point mutations (p = 0.001). The A2142C mutation was not detected. There was a significant difference in the A2143G mutation between the symptomatic and asymptomatic 5–18-year-old children (p = 0.019). Macrolides are frequently used to treat upper respiratory tract infections in children due to their selective pressure effect. We suggest that H. pylori strains carrying mutations in the 23S RNA subunit conferring clarithromycin resistance may lead to an intense inflammatory response in the gastric epithelial cells, allowing them to proliferate more rapidly and causing possible diarrhea, halitosis, or abdominal pain in children.

The Relationship between Anemia and Helicobacter Pylori Infection in Children

(1) Background: Many studies suggest that Helicobacter pylori (H. pylori) infection is associated with a higher prevalence of anemia. The aim of this study is to explore this fact for a pediatric population from the northeast of Romania; (2) Methods: A correlational retrospective study between infection with H. pylori and anemia was performed on a group of 542 children in a pediatric gastroenterology regional center in Northeast Romania; (3) Results: Out of 542 children with confirmed H. pylori infection, microcytic hypochromic anemia was present in 48 children, of whom 7 (14.5%) also had iron deficiency.; (4) Conclusions: The study results demonstrate a significant association of H. pylori infection with iron-deficiency anemia and iron deficiency in children in accordance with the results established in the published literature. Although the direct relationship between them it is not clear yet, prevention represents one of the first clinical measures that need to be implemented when encountering a refractory moderate to severe iron-deficiency anemia and, especially, when associated with gastrointestinal tract symptoms.

The Association between Helicobacter Pylori Infection and Iron Deficiency Anemia in Children: A Systematic Review and Meta-Analysis

Objectives This study, comprising a systematic review and meta-analysis, was conducted to assess the association between Helicobacter pylori infection and the risk of iron deficiency anemia (IDA) in children.

Methods We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant published studies were searched in the databases. Retrieved studies were assessed for quality using the Modified Newcastle-Ottawa Scale for quality assessment. The “meta” package of statistical software “R 4.0.3 was used for statistical analysis.

Results Overall, 22 eligible studies (eight cross-sectional, six randomized control trials, five case-control, two surveys, and one cohort), including nine (40.9%) from Asia, four (18.1%) from America, four (18.1%) from Africa, four (18.1%) from Europe, and one (4.5%) from Australia with a total of 3,434 cases and 4,455 controls were included in this systematic review and meta-analysis. We found that H. pylori infection was associated with a high risk of IDA (odds ratio 1.70, 95% confidence interval 1.21 − 2.38) in a random-effects model. Meta-regression analysis showed that none of the investigated factors that may affect the prevalence of IDA reached statistical significance. There was statistically significant difference between results when studies were categorized according to the methods used to diagnose H. pylori and level of incomes based on World Bank classification. The GRADEpro Guideline Development Tool evidence for the risk of IDA was of a “moderate certainty.”

Conclusions This meta-analysis with a “moderate certainty” of evidence showed an association between H. pylori infection and a high risk of developing IDA in children.

Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (FTIR) and Artificial Neural Networks Applied to Investigate Quantitative Changes of Selected Soluble Biomarkers, Correlated with H. pylori Infection in Children and Presumable Consequent Delayed Growth

Helicobacter pylori infections causing gastroduodenal disorders are a common medical problem. The aim of this study was to determine the specific motives of infrared spectroscopy (IR) spectra of sera from H. pylori-infected and uninfected children applied to investigate quantitatively-selected soluble biomarkers correlated with H. pylori infection in children and presumable consequent delayed growth. Sera from 41 children infected with H. pylori (Hp(+)) and 43 uninfected (Hp(-)) under the care of the Polish Mother's Hospital in Lodz, Poland, were analyzed. The H. pylori status was confirmed by gastroscopy, ¹³C urea breath testing, and anti-H. pylori IgG antibodies. Infrared spectra were measured using an FTIR/FT-NIR Spectrum 400 spectrometer (PerkinElmer). The IR spectrum was measured in the wavenumber range 3000-750 cm^-1 and subjected to mathematical calculation of the first derivative. Based on the chi-square test, 10 wavenumbers of spectra correlating with H. pylori infection were selected for use in designing an artificial neural network. Ten parts of the IR spectra correlating with H. pylori infection were identified in the W2 and W3 windows associated mainly with proteins and the W4 window related to nucleic acids and hydrocarbons. Artificial neural networks for H. pylori infection were developed based on chemometric data. By mathematical modeling, children were classified towards H. pylori infection in conjunction with elevated levels of selected biomarkers in serum potentially related to growth retardation. The study concludes that IR spectroscopy and artificial neural networks may help to confirm H. pylori-driven growth disorders in children.

Evaluation of Helicobacter pylori Infection, Neutrophil–Lymphocyte Ratio and Platelet–Lymphocyte Ratio in Dyspeptic Patients

Recent studies have shown a correlation between Helicobacter pylori (H. Pylori) infection and the neutrophil/lymphocyte ratio (NLR) and platelet/lymphocyte ratio (PLR). The aim of this study was to investigate the relationship between H. Pylori infection and hematimetric indices in patients with dyspepsia symptoms. Overall, 448 patients who underwent gastroscopy were analyzed retrospectively. Histopathological evaluation of biopsies according to H. pylori presence was classified as H. Pylori positive and negative groups, which are analyzed in relation with hematimetric indices. NLR and PLR measurements did not show a statistically significant difference between H. pylori negative and positive groups (p > 0.05). NLR revealed a negative correlation between hemoglobin (HGB), iron, and ferritin measurements in the correlation analysis of the H. Pylori positive group (r = −0.133, p = 0.031; r = −0.270, p = 0.002; r = −0.162, p = 0.032). Again, with PLR, there was a negative correlation between HGB, mean corpuscular volume (MCV), iron, and ferritin measurements (r = −0.310, p = 0.001, r = −0.187, p = 0.002, r = −0.335, p = 0.001; r = −0.290; p = 0.001). The results of our study do not reveal an association between H. pylori presence and inflammatory response, which is evaluated by NLR and PLR measurements in patients with dyspepsia. However, low serum iron and ferritin values of H. pylori-positive patients suggest the effect of H. pylori on iron metabolism.

Helicobacter pylori Prevalence and Impact: A Histology-Based Report About Children from an Endemic Country

Background

Helicobacter pylori is spreading worldwide with a high prevalence rate in the developing countries. Our primary goal was to measure the histology-based prevalence of Helicobacter pylori infection in children and to quantify its impact on the gastric inflammation and anemia. Our secondary goal was to study possible predictors for the presence of Helicobacter pylori in this cohort.

Methods

A retrospective chart review was performed for children who underwent Esophago-gastro-duodenoscopy at Jordan university hospital in Jordan from 2008 to 2016. Data collected included epidemiological data, indication for endoscopy, endoscopic findings, and laboratory data. The gastric biopsies were re-examined by a pathologist to check for the presence of Helicobacter pylori, the presence of gastritis, and to grade gastritis according to the updated Sydney criteria.

Results

A total of 98 children (53 girls-54%) underwent Esophago-gastro-duodenoscopy. The average age was 11.7 years ± 4.7 years. Of them, 53 patients (29 boys-55%) had Helicobacter pylori identified in the gastric biopsy. The histology-based prevalence rate of Helicobacter pylori was 54%. The most common indication for endoscopy was abdominal pain (53%) followed by vomiting (18%). Nodular gastric mucosa was present in 43% of the Helicobacter pylori-positive group, and in only 11% of the Helicobacter pylori-negative group (P-value <0.0.5). Moderate to severe chronic gastritis was seen in 59% of the biopsies of Helicobacter pylori-positive group, compared to 31% in the Helicobacter pylori-negative group (p value <0.05). Presence of anemia was not different between the two groups (p value > 0.05). Presence of endoscopic nodularity, active gastritis by histology, and moderate to severe gastritis by histology were positive predicators for the presence of Helicobacter pylori. (p value <0.05).

Conclusion

Helicobacter pylori infection in this study cohort of Jordanian children is common, with a histology-based prevalence rate of 54%. Nodularity of the stomach is the most common positive endoscopic feature, and its presence predicts the presence of Helicobacter pylori. Moderate to severe active gastritis is associated with Helicobacter pylori. The presence of Helicobacter pylori does not affect anemia status in this cohort of Jordanian children.

Helicobacter pylori infection is associated with fecal biomarkers of environmental enteric dysfunction but not with the nutritional status of children living in Bangladesh

Background

Because Helicobacter pylori (H. pylori) infection and Environmental Enteric Dysfunction (EED) follow a similar mode of transmission, there can be a complex interplay between H. pylori infection and EED, both of which can influence childhood growth. We sought to investigate the factors associated with H. pylori infection and identify its relationship with the fecal biomarkers of EED including Myeloperoxidase (MPO), Neopterin (NEO), Calprotectin, Reg1B and Alpha-1 antitrypsin (AAT), and nutritional status of the children.

Methodology

Data from an on-going community-based nutrition intervention study was used for this analysis. Total 319 children aged between 12–18 months were evaluated at enrolment and at the end of a 90-day nutrition intervention. Multivariable linear regression with generalized estimating equations was done to examine the association of H. pylori infection with stool biomarker of EED and nutritional status of the children.

Principal findings

One-fifth of the participants had H. pylori infection at both the time points, with 13.8% overall persistence. Children living in crowded households had higher odds of being infected by H. pylori (AOR = 2.02; 95% CI = 1.02, 4.10; p-value = 0.045). At enrolment, 60%, 99%, 69% and 85% of the stool samples were elevated compared to the reference values set for MPO, NEO, AAT and Calprotectin in the non-tropical western countries. The proportions reduced to 52%, 99%, 67%, and 77% for the same biomarkers after the nutrition intervention. Infection with H. pylori had significant positive association with fecal AAT concentrations (Coefficient = 0.26; 95% CI = 0.02, 0.49; p-value = 0.03) and inverse relationship with Reg1B concentrations measured in the stool samples (Coefficient = -0.32; 95% CI = -0.59, -0.05; p-value = 0.02). However, H. pylori infection was not associated with the indicators of childhood growth.

Conclusions

The study findings affirmed that the acquisition and persistence of H. pylori infection in the early years of life may exert an adverse impact on intestinal health, induce gut inflammation and result in increased intestinal permeability.

Infection with H. pylori, a substantial public health burden in the tropical countries, follows the similar mode of transmission analogous to Environmental Enteric Dysfunction (EED). There can be a complex interplay between H. pylori infection and EED–both of which can influence childhood growth–but the definite role of H. pylori infection contributing to EED and subsequent growth failure is poorly understood. In this study, the authors present data from an ongoing community-based nutrition intervention study and investigated the factors associated with H. pylori infection and identify its relationship with fecal biomarkers of EED and indicators of the nutritional status of the children hailing from a resource-poor urban settlement. They demonstrated the acquisition and persistence of H. pylori infection during early childhood. The study results also corroborate that infection with H. pylori had significant positive association with fecal Alpha-1 antitrypsin concentrations and an inverse relationship with Reg1B concentrations measured in stool samples of the children. The findings revealed in this study may contribute to a better understanding of the role of H. pylori infection in contributing to EED as well as alteration of gut function in the early years of life.

Association between Active H. pylori Infection and Iron Deficiency Assessed by Serum Hepcidin Levels in School-Age Children

Hepcidin regulates iron metabolism. Its synthesis increases in infection and decreases in iron deficiency. The aim of this study was to evaluate the relationship between H. pylori infection and iron deficiency by levels of hepcidin in children. A total of 350 school-age children participated in this cross-sectional study. Determinations of serum ferritin, hemoglobin, hepcidin, C-reactive protein, and α-1-acid-glycoprotein were done. Active H. pylori infection was performed with a 13C-urea breath test. In schoolchildren without H. pylori infection, hepcidin was lower in those with iron deficiency compared to children with normal iron status (5.5 ng/mL vs. 8.2 ng/mL, p = 0.017); while in schoolchildren with H. pylori infection the levels of hepcidin tended to be higher, regardless of the iron nutritional status. Using multivariate analysis, the association between H. pylori infection and iron deficiency was different by hepcidin levels. The association between H. pylori and iron deficiency was not significant for lower values of hepcidin (Odds Ratio = 0.17; 95% Confidence Interval [CI] 0.02-1.44), while the same association was significant for higher values of hepcidin (OR = 2.84; CI 95% 1.32-6.09). This joint effect is reflected in the adjusted probabilities for iron deficiency: Individuals with H. pylori infection and higher levels of hepcidin had a probability of 0.24 (CI 95% 0.14-0.34) for iron deficiency, and this probability was 0.24 (CI 95% 0.14-0.33) in children without H. pylori infection and lower levels of hepcidin. In children with H. pylori infection and iron deficiency, the hepcidin synthesis is upregulated. The stimulus to the synthesis of hepcidin due to H. pylori infection is greater than the iron deficiency stimulus.

Inflammatory responses induced by Helicobacter pylori on the carcinogenesis of gastric epithelial GES‑1 cells

Helicobacter pylori (HP) is a pathogenic bacterium associated with chronic gastritis, gastric ulcer and gastric cancer. In the present study, the primary carcinogenesis process of normal gastric epithelial cells (GES‑1) infected with HP was investigated. It was determined that infected gastric mucosal epithelial GES‑1 cells secreted increased interleukin‑8 (IL‑8) and IL‑23, and exhibited enhanced expression of inducible nitric oxide synthase and cyclooxygenase‑2, inducing inflammatory reactions and resulting in apoptosis. The bacterial infection significantly increased the expression of carcinogenesis‑associated genes, including p16, c‑Myc, p53 and p21, as well as the expression of cell surface signaling molecules cluster of differentiation 44 (CD44) and CD54 in GES‑1 cells or tissues of patients with gastritis and gastric cancer in vitro or in vivo. Simultaneously, the migration and invasion abilities of normal gastric epithelial GES‑1 cells were increased following HP infection. These observations demonstrated that the inflammatory response of HP infection could cause normal gastric epithelial cells to undergo significant cancerous reactions, indicating that HP is a risk factor for gastric cancer.

Diagnostic Workup and Micronutrient Deficiencies in Children With Failure to Thrive Without Underlying Diseases

OBJECTIVES AND STUDY

Failure to thrive (FTT) is an interruption in the normal pattern of growth. We aimed to evaluate the clinical characteristics, underlying etiologies, diagnostic workup, and frequency of micronutrient deficiencies (MDs) in children with FTT.

METHODS

This retrospective study was done with 729 children (319 male, mean age 6.8 ± 5.5 years) with FTT (weight for age <3rd percentile) who had visited the Pediatric Gastroenterology outpatient clinic between 2011 and 2016. Children who had previously known chronic diseases, inadequate intake, or inadequate absorption were excluded. Acute malnutrition was considered if weight-for-age z-scores were below -2 and height-for-age z-scores were above -2, and chronic malnutrition was defined if height-for-age z-scores were below -2.

RESULTS

The malnutrition rate was 57.1% (acute: 37.8%, chronic: 19.3%). Of children, 98.7% had laboratory evaluation. We found that 1.1% of laboratory tests, 0.4% of imaging studies, 27% of endoscopic findings, and biopsy results led to a specific diagnosis, equating to a total of 1.3% of diagnostic workup leading to a diagnosis related to FTT. The causes of FTT were inadequate nutrition (61.4%), psychiatric and behavioral disorders (17.2%), endocrinologic disorders (9%), recurrent infections (6.4%), gastrointestinal diseases (1.9%), and cardiac disorders (0.1%). Vitamin A and D deficiencies were the most common MD.

CONCLUSION

We showed that the most common cause of FTT is "purely nutrition" FFT because of inadequate caloric intake, and extensive diagnostic workup is rarely helpful to reveal the etiology. These results implicate the importance of clinical evaluation and anthropometry to evaluate a child with FTT.

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.

Highly clarithromycin-resistant Helicobacter pylori infection in asymptomatic children from a rural community of Cajamarca-Peru

Objective

The objective of this study was to determine the prevalence of clarithromycin-resistant Helicobacter pylori in asymptomatic children in a rural community of Cajamarca (northern Peru).

Results

Helicobacter pylori was detected in 17.2% (49/285) of the samples. Unboiled water consumption the most frequent associated factor in patients with positive PCR for H. pylori infection (93.9%). Clarithromycin resistant mutations were found in 79.6% (39/49) of the positive samples for H. pylori. The most frequent mutation was A2142G (46.9%), followed by the double-mutation A2142G–A2143G (28.6%).

Helicobacter pylori Infection in Pediatric Patients: Update on Diagnosis and Eradication Strategies

Helicobacter pylori infection is acquired mainly in childhood and remains an essential cause of peptic ulcer disease and gastric cancer. This article provides commentary on the last ESPGHAN/NASPGHAN guidelines and on publications made after the consensus conference of 2015. The majority of infected children are asymptomatic and pediatric studies do not support a role for H. pylori in functional disorders such as recurrent abdominal pain. The role of H. pylori infection in failure to thrive, children's growth, type I diabetes mellitus (T1DM), and celiac disease remains controversial. The diagnosis of infection should be based on upper-digestive endoscopy with biopsy-based methods. Eradication control after treatment should be based on validated non-invasive tests. Nodular gastritis is the main endoscopic finding of childhood H. pylori infection, but gastroduodenal erosions/ulcers are seen in some children, especially after 10 years of age. When indicated, eradication treatment should be given when good compliance is expected and based on the antimicrobial susceptibility profile.

IVTH BRAZILIAN CONSENSUS CONFERENCE ON HELICOBACTER PYLORI INFECTION

ABSTRACT Significant progress has been obtained since the III Brazilian Consensus Conference on H. pylori infection held in 2012, in Bento Gonçalves, Brazil, and justify a fourth meeting to establish updated guidelines on the current management of H. pylori infection. Therefore, the Núcleo Brasileiro para Estudo do Helicobacter pylori e Microbiota (NBEHPM), association linked to Brazilian Federation of Gastroenterology (FBG) held its fourth meeting again in Bento Gonçalves, RS, Brazil, on August 25-27, 2017. Twenty-six delegates, including gastroenterologists, endoscopists, and pathologists from the five regions of Brazil as well as one international guest from the United States, participated in the meeting. The participants were invited based on their knowledge and contribution to the study of H. pylori infection. The meeting sought to review different aspects of treatment for infection; establish a correlation between infection, dyspepsia, intestinal microbiota changes, and other disorders with a special emphasis on gastric cancer; and reassess the epidemiological and diagnostic aspects of H. pylori infection. Participants were allocated into four groups as follows: 1) Epidemiology and Diagnosis, 2) Dyspepsia, intestinal microbiota and other afections, 3) Gastric Cancer, and, 4) Treatment. Before the consensus meeting, participants received a topic to be discussed and prepared a document containing a recent literature review and statements that should be discussed and eventually modified during the face-to-face meeting. All statements were evaluated in two rounds of voting. Initially, each participant discussed the document and statements with his group for possible modifications and voting. Subsequently, during a second voting in a plenary session in the presence of all participants, the statements were voted upon and eventually modified. The participants could vote using five alternatives: 1) strongly agree; 2) partially agree; 3) undecided; 4) disagree; and 5) strongly disagree. The adopted consensus index was that 80% of the participants responded that they strongly or partially agreed with each statement. The recommendations reported are intended to provide the most current and relevant evidences to management of H. pylori infection in adult population in Brazil.

幽门螺杆菌感染与心血管疾病

随着社会经济的发展与生活方式的改变, 心血管疾病的发生率明显上升, 相关的危险因素包括年龄、吸烟、肥胖、糖尿病、高血压和血脂异常等, 但仍有一部分心血管疾病尚未发现确切病因. 近年来, 随着幽门螺杆菌(Helicobacter pylori, H. pylori)研究的不断深入, 发现其与多种胃肠外疾病的发生发展密切相关. 目前国内外多项研究探讨了H. pylori感染与心血管疾病的相关性, 多数研究认为心血管疾病患者H. pylori感染率明显增加, 联合H. pylori根除治疗有益于心血管疾病的防治, 但也有结果并不完全一致. 本文就心血管疾病中H. pylori感染的研究现状, 根除H. pylori对心血管疾病的影响以及H. pylori感染诱导心血管疾病的机制等方面的相关研究作一综述.

Helicobacter pylori infection and its related factors in junior high school students in Nagano Prefecture, Japan

BACKGROUND

There have been few reports on Helicobacter pylori (H. pylori) infection in asymptomatic Japanese children and adolescents. We hypothesized that the prevalence of H. pylori infection is very low among Japanese children and that clinical variables such as serum pepsinogen and iron levels are associated with H. pylori infection.

MATERIALS AND METHODS

We conducted a cross-sectional analysis of a sample of 454 junior high school students aged 12-15 years in four areas in Nagano Prefecture. A commercial ELISA kit (E-plate Eiken H. pylori antibody) was used to measure IgG antibody against H. pylori. Serum pepsinogen and iron levels were also measured using standard methods. A urea breath test was performed for seropositive students.

RESULTS

The overall prevalence of H. pylori was 3.1% (14/454). There were no significant differences in H. pylori prevalence among mountain, rural, and urban areas. The mean level of both serum pepsinogen (PG I) and PG II was significantly increased in the seropositive subjects compared with the seronegative subjects. When the cutoff values for adults (PG I: 70 ng/mL and PG I/II ratio: 3) were used, 4 of 14 subjects had PG I ≤70 ng/mL and PG I/II ratio ≤3. The results of a logistic regression analysis showed that low serum iron levels were significantly associated with H. pylori infection (P=.02).

CONCLUSIONS

The prevalence of H. pylori infection is as low as 3% among junior high school students aged 12-15 years in Japan. The disappearance of H. pylori is accelerating in Japanese children.

Helicobacter pylori infection is not associated with failure to thrive: a case control study

Purpose

The long-term impact of Helicobacter pylori infection is complex, and concerns about the need for eradication exist. We conducted this case control study to investigate the association between H. pylori infection and failure to thrive (FTT).

Patients and methods

From January 2009 to December 2011, 53 children with FTT group and matched children with the same sex and age and similar socioeconomic status without FTT (control group) were enrolled. A questionnaire was administered to the parents/guardian, and a ¹³C-urea breath test was performed to detect H. pylori infection.

Results

We found that the total prevalence of H. pylori infection was 29.2% and that there was no association between FTT and H. pylori infection (FTT group: 32%; control group: 26.4%; P=0.67). Short stature was more common in the FTT group and abdominal pain in the control group (FTT group: 37.7%; control group: 11.3%; P=0.003). In a comparison between the H. pylori-positive and -negative groups, abdominal pain (87.1% vs 64%; P=0.032) and the frequency of endoscopy (74.2% vs 32%; P<0.001) were significantly more common in the H. pylori-positive group.

Conclusion

We found that children with H. pylori infection are at an increased risk for abdominal pain and that FTT is not associated with H. pylori infection. The decision for eradication should be evaluated carefully and individualized.

The Centenary of Immune Thrombocytopenia-Part 2: Revising Diagnostic and Therapeutic Approach

Primary immune thrombocytopenia (ITP) is the most common cause of thrombocytopenia in children and adolescents and can be considered as a paradigmatic model of autoimmune disease. This second part of our review describes the clinical presentation of ITP, the diagnostic approach and overviews the current therapeutic strategies. Interestingly, it suggests an algorithm useful for differential diagnosis, a crucial process to exclude secondary forms of immune thrombocytopenia (IT) and non-immune thrombocytopenia (non-IT), which require a different therapeutic management. Advances in understanding the pathogenesis led to new therapeutic targets, as thrombopoietin receptor agonists, whose role in treatment of ITP will be discussed in this work.

Helicobacter pylori participates in the pathogenesis of IgA nephropathy

Increasing evidences have shown that Helicobacter pylori (Hp) is a pathogen closely related to extra-gastric disorders. Our previous in vitro studies had demonstrated that Hp infection, at least via cytotoxin-associated gene A protein (CagA), might play an important role in the pathogenesis of IgA nephropathy (IgAN) by stimulating proliferation and ectopic synthesis of aberrantly glycosylated IgA1 of B cells. However, the relevant clinical evidence of IgAN resulted from Hp infection remain to be elucidated. This study aimed to investigate the risk incidence of IgAN caused by Hp infection. 22 primary IgAN, 20 non-IgA nephropathy (n-IgAN), and 30 healthy controls were included in this study. We found that the rate of IgG anti-Hp seropositivity was significantly improved in IgAN, but the current Hp infection was similar in all groups. The production and underglycosylation of IgA1 tended to increase in IgAN patients with IgG anti-Hp seropositivity. A tendency toward increased the risk of clinical prognosis was seen in IgAN with Hp infection. Hp antigen and CagA were only deposited in renal tubules, and enhanced antigen deposition in response to Hp was observed in IgAN. Our study suggested that Hp infection might have a pathogenic role in IgAN through giving rise to strongly mucosal immune response, and based on damage of renal tubular.

Impact of Helicobacter pylori on the healing process of the gastric barrier

AIM

To determine the impact of selected well defined Helicobacter pylori (H. pylori) antigens on gastric barrier cell turnover.

METHODS

In this study, using two cellular models of gastric epithelial cells and fibroblasts, we have focused on exploring the effects of well defined H. pylori soluble components such as glycine acid extract antigenic complex (GE), subunit A of urease (UreA), cytotoxin associated gene A protein (CagA) and lipopolysaccharide (LPS) on cell turnover by comparing the wound healing capacity of the cells in terms of their proliferative and metabolic activity as well as cell cycle distribution. Toxic effects of H. pylori components have been assessed in an association with damage to cell nuclei and inhibition of signal transducer and activator of transcription 3 (STAT3) phosphorylation.

RESULTS

We showed that H. pylori GE, CagA and UreA promoted regeneration of epithelial cells and fibroblasts, which is necessary for effective tissue healing. However, in vivo increased proliferative activity of these cells may constitute an increased risk of gastric neoplasia. In contrast, H. pylori LPS showed a dose-dependent influence on the process of wound healing. At a low concentration (1 ng/mL) H. pylori LPS accelerated of healing epithelial cells, which was linked to significantly enhanced cell proliferation and MTT reduction as well as lack of alterations in cell cycle and downregulation of epidermal growth factor (EGF) production as well as cell nuclei destruction. By comparison, H. pylori LPS at a high concentration (25 ng/mL) inhibited the process of wound repair, which was related to diminished proliferative activity of the cells, cell cycle arrest, destruction of cell nuclei and downregulation of the EGF/STAT3 signalling pathway.

CONCLUSION

In vivo H. pylori LPS driven effects might lead to the maintenance of chronic inflammatory response and pathological disorders on the level of the gastric mucosal barrier.

Effect of Helicobacter pylori infection on growth trajectories in young Ethiopian children: a longitudinal study

BACKGROUND

Helicobacter pylori infection has been associated with early childhood growth impairment in high- and middle-income countries; however, few studies have examined this relationship within low-income countries or have used a longitudinal design. The possible effects of H. pylori infection on growth trajectories were examined in a cohort of young Ethiopian children.

METHODS

In 2011/12, 856 children (85.1% of the 1006 original singletons in a population-based birth cohort) were followed up at age 6.5 years. An interviewer-led questionnaire administered to mothers provided information on demographic and lifestyle variables. Height and weight were measured twice, and the average of the two measurements was used. Exposure to H. pylori infection was assessed using a rapid H. pylori stool antigen test. The independent associations of positive H. pylori infection status (measured at ages 3 and 6.5 years) with baseline height and weight (age 3 years) and height and weight growth trajectory (from age 3 to 6.5 years) were modelled using hierarchical linear models.

RESULTS

At baseline (age 3 years), the children's mean height was 85.7cm and their mean weight was 11.9kg. They gained height at a mean rate of 8.7cm/year, and weight at a mean rate of 1.76kg/year. H. pylori infection was associated with lower baseline measurements and linear height trajectory (β=-0.74cm and -0.79cm/year, respectively), after controlling for demographics and markers of socio-economic status. However, the positive coefficient was associated with quadratic growth in height among H. pylori-infected children (β=0.28, 95% confidence interval 0.07 to 0.49, p<0.01), and indicated an increase in height trajectory as the child increased in age. A non-significant difference in baseline and trajectory of weight was observed between H. pylori-infected and non-infected children.

CONCLUSIONS

These findings add to the growing body of evidence supporting that H. pylori infection is inversely associated with childhood growth trajectory, after controlling for a range of factors associated with reduced growth and H. pylori status. Further follow-up will be important to confirm possible catch-up in height trajectory among H. pylori-infected children as they grow older.

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 of Helicobacter pylori cagA, vacA, and iceA genotypes in children with gastroduodenal diseases]

OBJECTIVE

To investigate the prevalence of cagA, vacA, and iceA genotypes in the isolated strains of Helicobacter pylori (H.pylori) from children with gastroduodenal diseases in Jiangxi, China, as well as the association between cagA, vacA, and iceA genotypes and the type of gastroduodenal diseases.

METHODS

The samples of gastric antral mucosa were collected from 316 children with gastroduodenal diseases in Jiangxi, and a total of 107 strains of H.pylori were isolated. The genomic DNA of these strains was extracted, and PCR was used to determine the ureA, cagA, vacA, and iceA genotypes.

RESULTS

Of all the 107 isolated strains of H.pylori, the detection rates of ureA and cagA genes were 100% (107/107) and 94.4% (101/107) respectively. The overall detection rate of vacA gene was 100% (107/107), and the detection rates of vacAs1a, vacAs1c, vacAm1, and vacAm2 genes were 74.8% (80/107), 25.2% (27/107), 29.9% (32/107), and 69.2% (74/107) respectively, with both vacAm1 and vacAm2 genes detected in 0.9% (1/107) of all H.pylori strains. In the chimera of vacA gene, the detection rates of vacAs1a/m1, vacAs1a/m2, vacAs1c/m1, and vacAs1c/m2 genes were 26.2% (28/107), 51.4% (55/107), 3.7% (4/107), and 17.8% (19/107) respectively (P<0.001). The detection rates of iceA1 and iceA2 genes were 79.4% (85/107) and 9.3% (10/107), respectively (P<0.001), and both iceA1 and iceA2 genes were detected in 7.5% (8/107) of all strains. The detection rates of the genotypes of H.pylori showed no significant differences between the peptic ulcer, chronic gastritis, and duodenal bulbar inflammation groups (P>0.05).

CONCLUSIONS

The dominant genotypes of H.pylori are cagA, vacAs1a/m2, and iceA1, and there are mixed infections with H.pylori strains of different genotypes in children with gastroduodenal disease from Jiangxi, China. The genotypes of H.pylori are not associated with the type of gastroduodenal disease.

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.

Sequential Therapy is Superior to Triple Therapy for Helicobacter pylori Infection in Children: A Meta-Analysis

OBJECTIVES

To assess the efficacy and safety of 10-d sequential therapy compared to 5 to 14-d triple therapy for treating Helicobacter pylori infections in children according to the eradication rates.

METHODS

The Cochrane Library, MEDLINE, EMBASE, China National Knowledge Infrastructure databases, and other sources were searched in November 2014 without language restrictions. Randomized controlled trials (RCTs) that compared sequential therapy with triple therapy for H. pylori eradication in children were included. Dichotomous data were pooled to obtain the relative risk (RR) of the eradication rate with a 95% confidence interval (CI).

RESULTS

Fourteen RCTs with 1698 participants (718 and 980 for sequential and triple therapy, respectively) were included. The intention-to-treat eradication rates were 73% (95% CI: 70-76) and 66% (95% CI: 64-70) for sequential and triple therapy, respectively. The pooled RR was 1.16 (95% CI: 1.09-1.23), resulting in a number needed to treat of 16 (95% CI: 10-48), favoring sequential therapy. Sequential therapy was superior to 7- and 10-d triple therapy. Sequential and triple therapy did not differ significantly in the overall risk of adverse effects.

CONCLUSIONS

In children, sequential therapy appears to be superior to triple therapy for H. pylori eradication, although the eradication rates remain lower than the expected goal with both treatments. Factors-associated with a higher risk of eradication failure, such as compliance and antimicrobial resistance, remain insufficiently investigated. Therefore, further high-quality RCTs are needed to compare these different eradication treatment approaches.

Comparison of Gene Expression Between Pediatric and Adult Gastric Mucosa with Helicobacter pylori Infection

BACKGROUND

Although Helicobacter pylori infection among adults is a major risk factor for the development of gastric cancer and initial infection with H. pylori may occur before 5 years of age, the direct effects of H. pylori infection since childhood on gastric mucosa are unknown. The aim of this study was to evaluate gene expression in the H. pylori-infected gastric mucosa of children.

METHODS

Gastric mucosal samples were obtained from 24 patients (12 adults and 12 children) who had undergone endoscopic evaluation of chronic abdominal complaints and were examined by the adult and pediatric gastroenterologists at Juntendo University Hospital. Six adult and pediatric patients with and six without H. pylori infection were enrolled. Their gastric mucosal samples obtained from the antrum and corpus were used for microarray, real-time polymerase chain reaction, and immunohistochemical analyses to examine the expression of inflammatory carcinogenic molecules.

RESULTS

The expression of inflammatory molecules was upregulated in the H. pylori-infected gastric mucosa from both adults and children. The expression of olfactomedin-4 was only upregulated in adult patients, while that of pim-2, regenerating islet-derived 3 alpha, lipocalin-2, and C-X-C motif chemokine ligand 13 was equally upregulated in the infected gastric mucosa of both adults and children.

CONCLUSIONS

Because several carcinogenic molecules are upregulated in H. pylori-infected gastric mucosa even in children, early eradication therapy from childhood may be beneficial to decrease the incidence of gastric cancer. Although increased expression of olfactomedin-4 can be important in suppressing gastric cancer in adults, the increase was not detected in children.

Helicobacter pylori and allergy: Update of research

Recently a lot of literature has been published about the possible preventive action of Helicobacter pylori (H. pylori) against allergy. The present review summarizes research data about the association between H. pylori and allergic diseases, as well as discusses possible hypotheses about the preventive action of H. pylori against atopy. There is evidence from observational studies to support a weak inverse association between prevalence of H. pylori infection and allergy. However, confounders like some unidentified socioeconomic factors, antibiotic use and others could bias the association. Although data from cohort studies point to a possible association of H. pylori with some of the allergic diseases, no definite proof for causal relationship has been clearly demonstrated yet. A biological mechanism proposed to explain the preventive action of H. pylori to allergy is reduced exposure to a major stimulus for the generation of Treg cells in individuals without H. pylori infection. In addition, H. pylori could be an indicator for changes in gut microbiome, reflecting the complex interaction between microbes and immune system.

Polymorphisms at Locus 4p14 of Toll-Like Receptors TLR-1 and TLR-10 Confer Susceptibility to Gastric Carcinoma in Helicobacter pylori Infection

Helicobacter pylori (H. pylori) -induced gastric inflammation impacts the functions of leptin- and ghrelin-producing cells in the gastroduodenum. Inflammation resulting from H. pylori sensing via Toll-like receptors (TLRs) and the associated downstream signaling largely remain ambiguous. Here, we investigated the role of gut hormones, pro-inflammatory cytokines and single nucleotide polymorphisms (SNPs) associated with TLR 4p14 in H. pylori disease in 30 subjects with non-ulcer dyspepsia (NUD), 40 with peptic ulcer disease (PUD) and 15 with gastric cancer (GC) subjects positive and negative for H. pylori infection. The level of pro-inflammatory cytokines was directly proportional to the severity of gastritis, and disease status influenced the levels of gut hormones and pro-inflammatory cytokines. TLR-1 SNPs rs4833095 and TLR-10 SNPs rs10004195 and were directly associated with H. pylori disease, and were up-regulated in the presence of H. pylori in a genotype-independent manner. We concluded that TLR-1 rs4833095 and TLR10 rs10004195 confer susceptibility to development of gastroduodenal disease, especially GC in H.pylori disease.

Associations between peripheral vertigo and gastroesophageal reflux disease

We hypothesize that peripheral vertigo is associated with gastroesophageal reflux disease (GERD). Two mechanisms could be considered – gastric acids may directly irritate the respiratory mucosa and cause inflammation, or Helicobacter pylori (H. pylori) could be present and cause local infection. Reflux material (Hydrochloric acid (HCl) and pepsin) could get into the middle ear via Eustachian tube and affect osseous structures directly. Disturbance of ossicles could cause tinnitus, which is more common for peripheral vertigo. H. pylori could also get in the esophagus and in the upper respiratory tract via gastroesophageal reflux, and could cause tympanosclerosis and fixation of ossicles. In our study group, 120 of 153 (78.4%) patients had gastroesophageal reflux disease (GERD). Diagnostic tests of H. pylori (rapid urease test or blood antibody test) were performed for 96 of 120 (80%) patients with GERD and were found positive for 32 of 96 (33.3%) patients. Peripheral vertigo was present in 93 of 120 (77.6%) patients with GERD compared to 33 of 126 (26%) patients without GERD (χ(2)=9.016, p=0.003). H. pylori and peripheral vertigo coexisted in 26 of 126 patients (20.6%) (OR 1.36; 95% CI 0.49-3.74, p=0.55). Our study demonstrated statistically significant association between peripheral vertigo and GERD but not between peripheral vertigo and H. pylori. Further more extensive investigations are needed in order to explore our hypothesis.

Helicobacter pylori vs coronary heart disease - searching for connections

In this review, we discussed the findings and concepts underlying the potential role of Helicobacter pylori (H. pylori) infections in the initiation, development or persistence of atherosclerosis and coronary heart disease (CHD). This Gram-negative bacterium was described by Marshall and Warren in 1984. The majority of infected subjects carries and transmits H. pylori with no symptoms; however, in some individuals these bacteria may cause peptic ulcers, and even gastric cancers. The widespread prevalence of H. pylori infections and the fact that frequently they remain asymptomatic may suggest that, similarly to intestinal microflora, H. pylori may deliver antigens that stimulate not only local, but also systemic inflammatory response. Recently, possible association between H. pylori infection and extragastric disorders has been suggested. Knowledge on the etiology of atherosclerosis together with current findings in the area of H. pylori infections constitute the background for the newly proposed hypothesis that those two processes may be related. Many research studies confirm the indirect association between the prevalence of H. pylori and the occurrence of CHD. According to majority of findings the involvement of H. pylori in this process is based on the chronic inflammation which might facilitate the CHD-related pathologies. It needs to be elucidated, if the infection initiates or just accelerates the formation of atheromatous plaque.

Helicobacter pylori infection in Mongolian gerbils does not initiate hematological diseases

AIM: To investigate whether Helicobacter pylori (H. pylori) infection contributes to idiopathic thrombocytopenic purpura (ITP) or iron-deficiency anemia (IDA) onset in gerbils.

METHODS: A total of 135 Mongolian gerbils were randomly divided into two groups: an H. pylori infection group and a control group. Both groups were fed the same diet and the same amount of food. Each group was then divided into three subgroups, which were sacrificed at 6, 12, or 18 mo for analysis. At each time point, arterial blood was collected from the abdominal aorta and a complete blood cell count was analyzed in the clinical laboratory in the First Affiliated Hospital of Nanchang University.

RESULTS: There were no significant differences in platelet counts (938.00 ± 270.27/L vs 962.95 ± 162.56 × 10⁹/L), red blood cell counts (8.11 ± 1.25/L vs 8.44 ± 1.48 × 10¹²/L), or hemoglobin levels (136.9 ± 8.76 g/L vs 123.21 ± 18.42 g/L) between the control and the H. pylori groups, respectively, at 18 mo. With the exception of the mean corpuscular volume (MCV), all other indicators, including white blood cell counts, hematocrit, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, red blood cell distribution width, mean platelet volume, platelet distribution width, lymphocyte count, and lymphocyte count percentage, showed no significant differences between the control and H. pylori infection groups at each time point. The MCV in the H. pylori infection group (52.32 f/L ± 2.86 f/L) was significantly lower than the control group (55.63 ± 1.89 f/L) at 18 mo (P = 0.005), though no significant differences were observed at 6 (54.40 ± 2.44 f/L vs 53.30 ± 1.86 f/L) or 12 mo (53.73 ± 2.31 f/L vs 54.80 ± 3.34 f/L).

CONCLUSION: A single H. pylori infection is insufficient to cause onset of ITP or IDA and other factors may be required for disease onset.