Aims: Primary Helicobacter pylori infection occurs predominantly in childhood. The aims of this study were to establish the rate of H. pylori reinfection after successful eradication in children and adolescents and to determine the risk factors associated with reinfection.
Patients and methods: This retrospective study involved 45 children (20 girls, 25 boys) who met the following criteria: eradication of H. pylori confirmed at least 4 weeks after the completion of therapy, and the search for reinfection at least one year after control of eradication of H. pylori. Demographic data, socioeconomic status and living conditions were recorded.
Results: Forty-five children aged 1.2-17.6 years (median, 10.9 years) at the time of H. pylori treatment were reviewed 1 to 9 years after H. pylori eradication. Eight children (18%) had been reinfected (5.4% to 6% per patient-year). Six of 25 (24%) children older than 10 years at the time of diagnosis became reinfected. None of the studied risk factors was associated with reinfection. However, having a sibling younger than 5 years was found in four of seven (57%) reinfected children versus five of 24 (21%) nonreinfected children (p = .08).
Conclusion: Children become reinfected more frequently than adults. Adolescents become reinfected, whereas acquisition of primary H. pylori infection occurs predominantly in early childhood. Close contact with young children, especially siblings, younger than 5 years could be a more important risk factor than the age of the patient at the time of treatment for the high rate of reinfection in childhood.