SHORT REPORT Dietrich Rothenbacher Æ Viola Schultze Æ Peter Ja¨hnig Bruce Scharschmidt Æ Hermann Brenner Evidence of a rapid decrease in prevalence of Helicobacter pylori infection in children of a high risk group living in Germany Received: 17 November 2003 / Accepted: 11 February 2004 / Published online: 23 March 2004 Ó Springer-Verlag 2004 These data suggest that we might currently be witnessing a rapid decrease in the prevalence of Helicobacter pylori infection in Turkish children, formerly known as high risk group for this infection. The World Health Organization (WHO) estimates that about 50% of the world’s population carries Helicobacter pylori in the gastric mucosa. H.p ylori acquisition occurs mainly in early childhood. In a pre- vious study in a high risk group living in Germany, the acquisition of H. pylori infection was shown to occur mainly within the first 2 years of life [5]. We conducted another study in asymptomatic Turkish infants and toddlers living in Germany using an antigen assay for the detection of H. pylori in the stools to further investigate age at acquisition of the infection and to assess recent trends in infection prevalence in this group of children known to be at high risk of H. pylori infection. In this study we included all infants and toddlers of Turkish nationality in whom participating paediatri- cians from Ulm/Neu-Ulm and Frankfurt/Main per- formed a routine check-up or vaccination. The planned sample size was 200 divided into four equal age groups covering the range 0 to 24 months. The study was carried out between November 2001 and March 2002 and participation was voluntary. It was approved by the Ethics Committees of the University of Heidelberg and of the Medical Councils of the States of Baden-Wu¨rt- temberg, Bavaria and Hessen. Written informed consent was obtained from the parents in each case. We excluded all children who had received antibiotics, bismuth- compounds, proton-pump inhibitors, or H 2 -receptor antagonists within the 4 weeks prior to stool sampling. After being informed about the nature and purpose of the study, parents were asked to sign an informed consent document. The physician then completed a standardised questionnaire and obtained further infor- mation from parents and the child’s medical records. If a fresh stool sample was available at the time of the consultation, it was stored in a specimen container. Otherwise the parents were asked to collect a specimen and return the container on the same day or the fol- lowing day at the latest. The specimen was frozen and stored until analysed. The Premier Platinum HpSA Enzyme Immunoassay for the detection of H. pylori in stool (Meridian Diag- nostics Inc., Cincinnati, USA) was used to define current H. pylori infection status. The test was performed as instructed by the manufacturer. Results of the HpSA were read at 450 nm by spectrophotometry. An optical density >0.140 was defined as positive to detect H. pylori infection. All measurements were duplicated. In a recent study in 192 children aged 0.5 to 15 years (median 7.3 years), the sensitivity and specificity of the HpSA stool test were 95% and 98%, respectively in comparison with histology plus rapid urease test [3]. A similar study performed in 302 children aged 0.5–18.7 years, however, with a monoclonal stool test, resulted in a sensitivity and specificity of 98% and 99%, respec- tively (and in 94.4% and 99% in the relatively small number of children aged <6 years) [1]. A total of 216 children aged 3 to 24 months (mean age 11.7 months) were entered into the study; 106 were male and 110 female. All children were of Turkish nationality. The overall prevalence of H. pylori infection found in the study period was 8 out of 216 children (4%; 95% confidence interval 2%–7%). There were no differences between the various age groups (Table 1). In this group of Turkish children living in Germany (formally considered to be a high risk group), H. pylori prevalence was found to be only 4% within first 2 years This study was funded by the Chiron cooperation. D. Rothenbacher (&) Æ H. Brenner Department of Epidemiology, The German Centre for Research on Ageing (DZFA), Bergheimer Strasse 20, 69115 Heidelberg, Germany E-mail: rothenbacher@dzfa.uni-heidelberg.de Tel.: +49-6221-548146 Fax: +49-6221-548142 V. Schultze Æ P. Ja¨hnig Æ B. Scharschmidt Chiron Cooperation, Emeryville, CA, USA Eur J Pediatr (2004) 163: 339–340 DOI 10.1007/s00431-004-1427-8