Relationship between Helicobacter pylori detection and an increased risk of infection in childhood

Venerando R (1, 2), Rasmussen LT (1, 3), de Labio RW (4), Gatti LL (2), Francisco O (2), Viani GA (5), Rivera LML (1), Payão SLM (1, 4)

(1) Sacred Heart University, Bauru, São Paulo State, Brazil; (2) Ourinhos Integrated College (FIO), Ourinhos, São Paulo State, Brazil; (3) Department of Morphology and Genetics, Federal University of São Paulo (Unifesp), São Paulo, São Paulo State, Brazil; (4) Department of Genetics, Famema Blood Center, Marília Medical School (Famema), Marília, São Paulo State, Brazil; (5) Department of Radiotherapy and Oncology, Marília Medical School (Famema), Marília, São Paulo State, Brazil.

Abstract: The risk of developing gastric cancer is believed to be related to differences among Helicobacter pylori strains and the inflammatory responses mediated by host genetic factors. H. pylori infection is acquired at an early age and in the absence of appropriate antibiotic therapy, it generally persists for life. Tp53 gene regulates the transcription of several cytokines and chemokines involved in innate immunity and its action may be influenced by the presence of different H. pylori strains. The present study aimed to detectH. pylori in pediatric patients, to accessTp53 polymorphism at codon 72 and to correlate such findings with age and histopathological results. Three hundred and forty-two patients were analyzed. DNA from their gastric biopsies was extracted and the detection of H. pylori was performed through polymerase chain reaction assays, urease test and histopathologic examination. Allelic discrimination of SNP rs1042522 (Tp53) was performed by real-time polymerase chain reaction. Our results suggest a possible relationship between the presence of H. pylori and chronic gastritis in children and young patients, and showed a significant association between ageing and positivity for H. pylori. It was verified that patients aged ≤ 10 years were 1.3 times more likely to have infection by H. pylori when compared with those aged > 10 years. Finally, no association was found between Tp53 polymorphisms and the presence of H. pylori.

Key words: Helicobacter pylori, childhood, Tp53 polymorphims, PCR.

ACKNOWLEDGMENTS

The authors would like to thank The State of São Paulo Research Foundation (FAPESP), Sacred Heart University (USC) and Marília Medical School (FAMEMA).

COPYRIGHT

© CEVAP 2012

SUBMISSION STATUS

Received: February 10, 2012.

Accepted: August 23, 2012.

Abstract published online: September 3, 2012.

Full paper published online: November 30, 2012.

CONFLICTS OF INTEREST

The authors declare no conflicts of interest.

FINANCIAL SOURCE

The State of São Paulo Research Foundation (FAPESP) provided the financial grants (project number 06/60836-1).

ETHICS COMMITTEE APPROVAL

The present study was approved by the Ethics Committee of Sacred Heart University, Bauru, SP, Brazil, under the following numbers: 056/2005 and 223/2011.

CORRESPONDENCE TO

Spencer Luiz Marques Payão, Laboratório de Genética, Hemocentro, FAMEMA, Rua Lourival Freire, 240, Bairro Fragata, Marília, São Paulo, 17519-050, Brasil. Phone: +55 14 3402 1856. Fax: +55 14 3433 0148. Email: slmpayao@famema.br.