RESUMO
OBJECTIVE: Helicobacter pylori and Epstein-Barr virus (EBV) infections are common world-wide. Though H. pylori infection is a major factor in gastroduodenal diseases, its role in association with EBV infection is unknown. We prospectively studied the association of H. pylori and EBV in patients with gastric cancer (GC) and peptic ulcer disease (PUD). MATERIAL AND METHODS: A total of 348 adult patients (non-ulcer dyspepsia (NUD) 241, PUD 45, GC 62) undergoing upper gastrointestinal endoscopy between September 2003 and May 2007 were enrolled in the study. H. pylori infection was diagnosed by rapid urease test, culture, histopathology and polymerase chain reaction (PCR). EBV DNA was detected by non-polymorphic Epstein-Barr nuclear antigen-1 (EBNA-1) gene-based PCR and sequence analysis. RESULTS: The rate of H. pylori infection was higher in patients with PUD than in those with GC (80% versus 56.5%, p=0.01) and NUD (80% versus 55.2%, p=0.002). In patients with GC and PUD, EBV DNA was detected more often than in those with NUD (GC versus NUD - 82.3% versus 37.3%, p<0.001; PUD versus NUD - 75.5% versus 37.3%, p<0.001). H. pylori infection and EBV DNA detected in different groups of patients was as follows: 62.2% in PUD, 46.8% in GC and 29.5% in NUD. PUD and GC were significantly associated (p<0.001 and <0.05, respectively) with the presence of H. pylori infection and EBV DNA as compared with NUD. CONCLUSIONS: EBV DNA either alone or in combination with H. pylori infection was significantly associated with GC and PUD, suggesting that EBV might play an important role in gastroduodenal pathology.