Association between Helicobacter pylori Infection and Iron Deficiency Anemia in School-aged Iranian Children

Antibiotic resistance and virulence genes in Helicobacter pylori strains isolated from children in Shanghai, China (2019-2022)

BACKGROUND

The increasing prevalence of antibiotic-resistant Helicobacter pylori strains poses a significant threat to children's health. This study investigated antibiotic resistance rates in Helicobacter pylori strains isolated from children in Shanghai and analyzed the presence of virulence genes in these strains.

METHODS

We obtained 201 Helicobacter pylori strains from pediatric patients with upper gastrointestinal symptoms who underwent gastrointestinal endoscopy between 2019 and 2022. Subsequently, we performed antibiotic susceptibility tests and virulence gene PCR assays on these strains.

RESULTS

Helicobacter pylori resistance rates of 45.8%, 15.4%, 1.0%, and 2.5% were detected for metronidazole, clarithromycin, amoxicillin, and levofloxacin, respectively. Among all isolates, 64.7% exhibited resistance to at least one antibiotic. Resistance to metronidazole and clarithromycin increased from 2019 to 2022. The predominant vacA gene subtype was vacA s1a/m2. The prevalence of vacA m2 and dupA exhibited an upward trend, while oipA presented a decreasing trend from 2019 to 2022. The prevalence of dupA was significantly higher in gastritis than peptic ulcer disease, and in non-treatment compared to treatment groups.

CONCLUSIONS

Helicobacter pylori antibiotic resistance remains high in children and has risen in recent years. Therefore, the increasing use of metronidazole and clarithromycin requires increased monitoring in children. No association was observed between antibiotic resistance and virulence gene phenotypes.

Helicobacter pylori-Related Extraintestinal Manifestations—Myth or Reality

It is well documented that Helicobacter pylori (H. pylori) can cause both gastrointestinal and extraintestinal manifestations. The latter one represents a major burden in terms of diagnosis and treatment. H. pylori-associated systemic subclinical inflammation is mostly responsible for the development of extraintestinal manifestations, and its early eradication might result in preventing all adverse events related to their occurrence. Thus, it was suggested that H. pylori might be associated with iron deficiency anemia, thrombocytopenia (immune thrombocytopenic purpura), Schonlein Henoch purpura, failure to thrive, vitamin B12 deficiency, diabetes mellitus, body mass index, cardiovascular diseases, as well as certain neurological conditions. Nevertheless, studies showed both pros and cons in terms of the role of H. pylori in the development of previously mentioned clinical entity underlining the crucial need for further studies on these topics. Although most of these extraintestinal manifestations occur during adulthood, we must not forget that H. pylori infection is acquired mainly during childhood, and thus its early diagnosis and eradication might represent the cornerstone in the prevention of H. pylori-induced inflammatory status and consequently of all related extraintestinal conditions.

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.

Prevalence of Helicobacter pylori Infection among Anemic School-Age Children in Egypt: A Cross-Sectional Population-Based Study

Anemia and Helicobacter pylori infection in school-age children are important public health problems. The association between H. pylori infection and the development of anemia, especially iron deficiency anemia, has been previously studied and until now it is still a matter of argument. This study aimed to determine the prevalence of anemia and H. pylori infection among school-age children and to find the association between H. pylori infection and anemia in school-age children. We conducted this population-based cross-sectional study in six Egyptian primary schools over a 12-month-period, including 1,200 students from all grades who fulfilled the inclusion criteria. The study participants were subjected to the following: medical history, clinical examination, and laboratory investigations included complete blood count and H. pylori antigen in stool, and according to the level of hemoglobin (Hb), we divided the students into two groups; the anemic group with Hb level <11.5 g/dL and nonanemic group with Hb level ≥11.5 g/dL, and the serum ferritin levels were measured only for the anemic group as the best indicator for iron status. The overall prevalence of H. pylori infection was 25%. The overall prevalence of anemia was 13.25%, of which hypochromic microcytic anemia represented 87.4% of the anemic group, and the mean ferritin level in the anemic group was 18.56 ± 9.96 ng/mL. The prevalence of anemia among H. pylori-infected patients (62.3%) was significantly (p < 0.001) higher than in noninfected children (37.7%). In the anemic group, the mean ferritin level in H. pylori-infected children was significantly lower than the mean level in the noninfected children (p <0.001). Furthermore, the anemic group had a significantly higher incidence of H. pylori infection and a lower age (p <0.001) in comparison with the nonanemic group. The dominant type of anemia in H. pylori-infected children was the microcytic hypochromic anemia, with a significantly higher incidence in comparison to other types of anemia (p <0.001). The findings of this study demonstrate a significant association between H. pylori infection and anemia in school-aged children, especially iron deficiency anemia, as the incidence of H. pylori infection was greater in anemic children than in non-anemic children.

Review: Helicobacter pylori infection in children

Helicobacter pylori infection in children and adolescents differs in comparison to adults with respect to epidemiology, host responses, and disease manifestations. Furthermore, treatment options are limited in this population and antibiotic resistance rates continue to increase. Therefore, ongoing research is vital to understand disease pathogenesis and provide optimal management of children with infection. This review summarizes relevant publications from April 2019 to March 2020. Similar to adults, recent studies show a decreasing prevalence of infection in the pediatric population. Studies of pathogenesis investigated serum immune responses and the potential inverse association of infection and allergy. Several studies investigated the effect of H pylori and related inflammation on the gut microbiome. The recommendation of endoscopy-based testing to identify the cause of symptoms and not just H pylori, reserving noninvasive UBT or stool antigen tests for post-eradication follow-up, was supported by the current literature.