The Association of Helicobacter Pylori CagA Sero-Prevalence, Serum Pepsinogens as Markers of Gastric Inflammation with Asthma in Children: A Case-Control Study

Background:Infections during childhood might affect the risk of asthma; however, conflicting evidence exists regarding the association between H.pylori infection and asthma. We examined the associations of H.pylori sero-prevalence and pepsinogens, as markers of gastric inflammation with asthma in children.

Methods:A case-control study was conducted among children aged 4.8-17.3 years at the pediatric department at the French hospital in Nazareth. Confirmed asthma cases(n=75) were recruited through the pulmonary clinic, and controls(n=160) without history of asthma were recruited among children visiting the emergency room or admitted to the pediatric department. Using enzyme linked immunosorbent assays we measured the presence H.pylori IgG antibody and cytotxin associated gene A antigen , virulent phenotype IgG antibody and concertation of serum PGs.

Results:H.pylori IgG sero-positivity was 25% and 40% among cases and controls, respectively (P=0.03). The respective figures were 18% and 21%, P=0.12 for CagA negative phenotype and 7% and 16%, P=0.039 for CagA positive phenotype. A multivariable model showed adjusted OR 0.62 (95% CI 0.29-1.32), P=0.2 and 0.39 (95% CI 0.14-1.15), P=0.08, for CagA negative and positive phenotypes, respectively. H.pylori sero-positive children with a PGI: PGII of ≤6.78 (lowest quartile, as a proxy of severe gastric inflammation) had 68% lower odds to have asthma (P=0.033) than sero-negative children. There was no significant difference between H. pylori sero-positive and negative asthmatic children in pulmonary function.

Conclusions:Inverse association was found between H.pylori sero-prevalence, especially with CagA phenotype, and asthma among school-age children. H. pylori sero-positive children, with low PGI:PGII ratio, indicating more severe gastritis, were less likely to be asthmatic than H.pylori sero-negative children.