Helicobacter pylori infection in Finnish children and adolescents. A serologic cross-sectional and follow-up study.

Abstract

The purpose was to examine the epidemiology of Helicobacter pylori infection in Finnish children and adolescents. Blood samples taken from healthy subjects (n = 461) 3-18 years old were studied cross-sectionally for the presence of H. pylori antibodies. Additionally, blood samples drawn in 1980, 1983, 1986, and 1989 from 74 children born in 1977 were tested. Serum IgG-class antibodies to H. pylori were determined by an enzyme immunoassay. In the cross-sectional series the mean antibody levels and the percentage of seropositive children increased with age. The overall seroprevalence was 10.2%. During the follow-up period from 3 to 12 years of age the seropositivity increased from 4.6% to 5.7%. On the basis of the seroconversions between 3 and 12 years of age the annual incidence of H. pylori infection was calculated to be only 0.3%. In children seropositivity for H. pylori of the IgG class is often a sign of an infection acquired in early childhood. It seems likely that the age-dependent increase in the seropositivity reflects cumulation of a chronic infection.