Clinical relevance of Helicobacter pylori CagA-positive strains: gastroduodenal peptic lesions marker.

OBJECTIVES

peptic ulcer is characterized by its recurrent nature, which necessitates maintenance treatment in most patients. But this natural history can be changed in patients with peptic ulcer associated to Helicobacter pylori, as shown by the low rates of recurrence and decreased hemorrhagic recidivism associated with this infection. Whether CagA or VacA strains are associated with a greater risk of peptic ulcer is controversial. This study was designed to examine endoscopic findings and their relation with H. pylori phenotype (CagA or VacA).

METHODS

106 selected dyspeptic patients underwent upper gastrointestinal tract endoscopic examination between September 1996 and May 1997 [69 with H. pylori (Hp) and 37 without this infection]. Endoscopic findings were classified as gastric ulcer (GU), duodenal ulcer (DU), gastric erosions (GE), duodenitis (Du), chronic gastritis (CG) and normal mucosa (NM). Hp phenotype was analyzed with a western blot test.

RESULTS

75% of H. pylori strains were CagA-positive and 54.2% were VacA-positive. 82.4% of the cases of DU were associated with a CagA+ phenotype, but the association was not statistically significant. Otherwise 100% of gastric ulcers were associated with CagA+ strains (p < 0.005). VacA phenotype was not associated with any particular endoscopic finding. Peptic ulcer (DU or GU) was also associated with the CagA+ phenotype (p < 0.05).

CONCLUSIONS

the CagA+ H. pylori phenotype seems to be a peptic lesion marker, but was more frequently related with GU than with DU in our sample of Spanish patients.