SEROCONVERSION FOR HELICOBACTER-PYLORI

The prevalence of Helicobacter pylori antibodies increases with age, b ut it is unknown whether this is due to a constant rate of infection i n different age groups, or whether most infection occurs in childhood. Follow-up data on infection rates and the course of infection in an u ntreated population are scarce. We measured H pylori IgG antibody conc entrations in patients who were seen at our endoscopy unit between 197 9 and 1983. 115 of 164 eligible patients (70%) participated in the stu dy. H pylori IgG antibody concentrations were measured in two serum sa mples taken with a mean interval of 11.5 years. 56 patients tested pos itive at the first visit. During follow-up, 2 patients became infected (annual infection rate 0.30%, 95% CI 0.04-1.08%). Evidence of infecti on disappeared in 6 patients: after gastric surgery in 3 and due to an unknown cause in the remaining 3 patients. A non-significant decrease of infection was shown in different age cohorts during follow-up. Ant ibody concentrations did not increase with age. These results strongly support the concept of dominant infection rates in childhood. Elimina tion of infection may occur in a few patients without eradication ther apy.