Relación entre detección de anticuerpos anti-CagA, sensibilidad antibiótica y úlcera péptica en pacientes con infección por Helicobacter pylori

Abstract

The aim of this study was to determine the relationship among antibodies against virulence factors (CagA and VacA), clinical status and primary resistance in dyspeptic patients with Helicobacter pylori infection. Ninety-eight adult patients with Helicobacter pylori infection who underwent gastric endoscopy for dyspepsia were studied. Specific serum IgG antibodies against CagA and VacA proteins were detected by Western-blot (Helicoblot 2.0). Minimum inhibitory concentrations of metronidazole, amoxicillin, tetracycline and clarithromycin were determined with the E-test. Thirty-nine patients presented peptic ulcer disease and 59 had non-ulcer dyspepsia. CagA protein was detected in 63 patients, and VacA protein in 52 subjects, and both were significantly associated with peptic ulcers (p 5 0.034 and p 5 0.029, respectively). Susceptibility results showed 38.8% of strains resistant to metronidazole and 10.3% resistant to clarithromycin. No resistance to amoxicillin or tetracycline was found. Susceptibility to clarithromycin was more frequent in ulcer patients than in non-ulcer dyspepsia patients (p 5 0.046). CagA protein was more frequent in patients with clarithromycin-sensitive strains (p < 0.001). Antibodies against CagA protein were associated with higher antibiotic susceptibility in patients with ulcers or non-ulcer dyspepsia. Thus, anti-CagA antibody detection could be a useful marker of favorable prognosis with antibiotic treatment.