Seroprevalence of Helicobacter pylori in German infants and children

The purpose of the study was to evaluate the serological prevalence of Helicobacter pylori (H. pylori) infection during infancy and childhood in Germany.

We quantified specific IgG antibody titers against H. pylori by enzyme-linked immunosorbent assay (ELISA) technique (BIO-RAD G.A.P. IgG-test) from healthy children under 18 years (n = 216) admitted to hospital for minor surgical procedures. All patients were age 0-18 years and lived in the southern part of Germany (Bavaria and Baden-Wuerttemberg). For each age group, 12 different sera were obtained and were determined in duplicate. We analyzed the 216 sera within 6 age groups of equal size. Mean titers > 19 U/ml were considered positive for H. pylori infection.

None of the sera of 48 children less than 4 years old were positive for anti-H. pylori specific IgG antibodies. Titers above 19 U/ml were found in 8.3% (3/36 sera each, CI 95% 1-21.7%) in the children age three to five and nine to 11 years. Six- to eight-year-old children showed a 19.4% seroprevalence (7/36 sera, CI 95% 8.2-48%) and children 12-14 years old showed a seropositivity of 16.7% (6/36 sera, CI 95% 6.6-46.1%). In contrast, 47.2% (17/36 sera, CI 26.5-70.3%) of the adolescents older than 14 years had positive H. pylori antibody titers (p < .01, compared to the age-group 12-14 years). The test for linear trend (seropositivity and age) was significant with p < .001. The overall incidence increase with age in prevalence of H. pylori infection was found to be 0.9% per year within this population.

In contrast to published data from other European and non-European countries, we could not detect H. pylori infection in German infants less than four years old by measurement of IgG antibodies. In the older subjects, seropositivity increased significantly and linearly with age.