Serum CagA and VacA antibodies and risk for peptic ulcer disease in subjects with Helicobacter pylori infection

BACKGROUND: The presence of cagA antibodies constitutes a serum marker of infection caused by virulent strains of Helicobacter pylori. The objective of this study was to determine the risk of peptic ulcer in patients with H. pylori infection, in relation to the detection of CagA and VacA antibodies, PATIENTS AND METHOD: Prospective case-control study including 104 peptic ulcer patients with active H. pylori infection (positive urease test and/or histology, or positive urea breath test) and 104 age- and sex-matched controls, without peptic ulcer history, with active H. pylori infection (positive urea breath test), Serum CagA and VacA antibodies were determined by Western blot. Non-steroidal antiinflamatory drugs (NSAID) use was determined by structured data collection. A multivariate analysis (logistic regression) was carried out to determine the odds ratio (OR). RESULTS: Presence of serum antibodies against CagA was higher in peptic ulcer patients (74%) than in controls (46.2%) (OR = 5.7; 95% CI = 2.1-15.6). However, presence of serum antibodies against VacA in patients (46.2%) was similar to that in controls (36.5%). NSAID use was also more frequent in patients (51.9%) than in controls (21.2%) (OR = 6.5; 95% CI = 2.2-19.5). CONCLUSIONS: Serum antibodies against CagA and use of NSAID are the most important risk factors for peptic ulcer disease.