In our study, the association was shown to be specific to active H. pylori infection. This association was not found with past H. pylori infection, suggesting that either past infection are not relevant, the school children can improve their iron INCB024360 status when the infection is cleared, or these are only false positive results. Some studies suggest that

active infection causes deterioration in nutritional iron status: A meta-analysis included 15 observational studies in which the infection was detected by UBT or by serological test. In the studies that detected the infection by UBT, the association between ID and H. pylori infection showed an OR of 5.88. In the studies where the infection was detected by serological test that quantitate whole-cell H. pylori antibodies, it was 2.16 [45]. The results show that serological test in the evaluation of this association may lead to misclassification of H. pylori status at the time when the blood sample is obtained and subsequently attenuate the association [23]. The cross-sectional Everolimus chemical structure nature of our study limited the possibility to make inferences about causality and the direction of associations.

Temporal ambiguity bias may be present. We can speculate that children with worse nutritional status have higher risk of H. pylori acquisition but, as it has been suggested by other authors, it is also possible that active H. pylori infection has negative effects on iron status and on growth rate velocity [17, 21, 23]. In this study, school children with evidence of past H. pylori infection had similar percentages

of iron deficiency and of low height for age than children without H. pylori infection. In this population, we have reported that spontaneous clearance of active infection is not rare [9]. It is possible that those children able to eradicate the infection have better nutritional and health status than children with persistent infection. But it is also possible that clearance of infection per se led to the improvement of these children’s nutritional status. ADAMTS5 In conclusion, the reported prevalence of H. pylori infection depends on the detection test utilized. The results obtained by different tests are in relation with the colonization status at the moment in which the samples are taken. Overall, results suggested that active H. pylori infection is associated with deficient nutritional status in school children. This study was supported in part by grants from the National Council of Science and Technology (project No. 69667) and from Fund of Health Research, Mexican Institute of Social Security (projects 2005/1/I/089 and 190). Competing interests: The authors have no conflicts of interest to declare. “
“Background:  The human bacterial pathogen Helicobacter pylori forms biofilms. However, the constituents of the biofilm have not been extensively investigated. In this study, we analyzed the carbohydrate and protein components of biofilm formed by H.