Roma E, Miele E. Helicobacter pylori infection in pediatrics. Helicobacter. 2015 Sep;20 Suppl 1:47-53.
This review includes the main pediatric studies published from April 2014 to March 2015. The host response of Treg cells with increases in FOXP3 and TGF-β1 combined with a reduction in IFN-γ by Teff cells may contribute to Helicobacter pylori susceptibility in children. Genotypic variability in H. pylori strains influences the clinical manifestation of the infection. Helicobacter pylori infection is associated with variables indicative of a crowded environment and poor living conditions, while breast-feeding has a protective effect. Intrafamilial infection, especially from mother to children and from sibling to sibling, is the dominant transmission route. Studies showed conflicting results regarding the association between H. pylori infection and iron deficiency anemia. One study suggests that H. pylori eradication plays a role in the management of chronic immune thrombocytopenic purpura in H. pylori-infected children and adolescents. The prevalence of H. pylori was higher in chronic urticaria patients than in controls and, following H. pylori eradication, urticarial symptoms disappeared. An inverse relationship between H. pylori infection and allergic disease was reported. Antibiotic resistance and insufficient compliance to treatment limit the efficacy of eradication therapy.
Queiroz DM, et al. Iron status and Helicobacter pylori infection in symptomatic children: an international multi-centered study. PLoS One. 2013 Jul 4;8(7):e68833.
“Conversely, in the United Kingdom cohort, the very low prevalence of H. pylori infection in an ethnically diverse group of children might explain the absence of association between the infection and iron deficiency/IDA parameters. A decreased prevalence of H. pylori infection associated with different generations of immigrants from developing to developed countries was similarly described by Tsai et al.  with Hispanics in the USA, likely reflecting a better standard of socioeconomic conditions. Thus, geographical variability among iron stores of the children may also explain the differences between the Latin American and UK cohorts we observed. Due to inadequate diet, children from developing countries could have a small iron reserve that contributes to the development of iron deficiency and IDA in the course of H. pylori infection.”
Vendt N, et al. Iron deficiency and Helicobacter pylori infection in children. Acta Paediatr. 2011 Sep;100(9):1239-43.
“We studied a school aged outpatient-based population and found that the prevalence of H. pylori infection was lower among younger study subjects. It is known that contamination with H. pylori infection increases at school age and decreases in adulthood (9,17). H. pylori infection is less prevalent in younger generations than in older ones because the risk of contracting prevalent H. pylori infection in childhood has substantially decreased over recent decades
because of diminishing acquisition, or increased loss or both. Thus, the declining prevalence of H. pylori infection in younger generations in industrialized countries might be the expression of the birth cohort. The birth cohort effect is defined as the prevalence of H. pylori infection that arises from different exposures to casual factors in different birth cohorts in the population as the environment and society change .”
Hajikano M, et al. Helicobacter pylori infection with a duodenal ulcer in a 6-year-old boy. J Nippon Med Sch. 2006 Oct;73(5):292-6.
A 6-year-old boy was hospitalized because of dark feces and facial pallor of 1 weeks duration. Other gastrointestinal symptoms, including vomiting and abdominal pain, were absent, but he felt dizziness when standing and fatigue on effort. Hematologic studies revealed iron-deficiency anemia, and endoscopy showed gastric erosions and a duodenal ulcer. All test results for Helicobacter pylori infection, including H. pylori antigen in stool, anti-H. pylori IgG immunoassay in serum, and the (13)C-urea breath test, were positive. Because an H. pylori-associated gastric ulcer had been diagnosed with endoscopy in the patients father 3 years earlier, father-son transmission was suspected. The patient was treated with triple-agent eradication therapy (proton pump inhibitor [lansoprazol], amoxicillin, and clarithromycin) for 2 weeks. One month after therapy was completed, eradication of H. pylori was confirmed by negative results on the stool antigen test. Peptic ulcer disease can occur in young children, as in this case. The stool antigen test kit is a useful and reliable method that can be used even in preschool children to diagnose H. pylori infection.
DuBois S, Kearney DJ. Iron-deficiency anemia and Helicobacter pylori infection: a review of the evidence. Am J Gastroenterol. 2005 Feb;100(2):453-9.
Unexplained IDA is a frequent indication for endoscopic evaluation of the gastrointestinal tract. However, a specific etiology cannot be identified in a significant proportion of patients. Epidemiologic studies support an association between H. pylori infection and lower iron stores, and small, uncontrolled case series (and a single, small, randomized trial) have shown improvement in anemia following H. pylori treatment. H. pylori infection is widespread, and it is unclear why only a small proportion of individuals develop clinical complications, including iron deficiency. The available evidence suggests that person at increased risk of iron deficiency, such as premenopausal women and children, are more likely to develop iron deficiency associated with H. pylori infection. Further study, including larger randomized trials, is needed to clarify whether patients with unexplained iron deficiency benefit from H. pylori treatment. However, the evidence that currently exists supports an association between H. pylori infection and IDA, and testing and treatment of persons with unexplained IDA for H. pylori infection is
a reasonable practice, and is recommended by the authors. Further studies are required to confirm a causal relationship
and explore mechanisms of disease.
More PubMed results on IDA and H. pylori infections.