Colonisation density and topographic localisation of Helicobacter pylori do not depend on the cagA status.

AIMS

To explore the correlation between the cagA status of Helicobacter pylori and the density and topographic localisation of H pylori.

METHODS

Gastric antral biopsy specimens were taken from 716 consecutive patients, including 293 H pylori positive patients (124 men, 169 women; mean age, 52.6 years; range, 12-87). A serum sample was taken for determination of IgG anti-CagA antibodies (sensitivity of 94.4% and specificity of 92.5%). The density of H pylori was assessed semiquantitatively (grades I-IV) in biopsy specimens stained with the modified Giemsa stain. Topographic localisation was classified as follows: score A, H pylori closely attached to the mucosa; score B, H pylori attached to the mucosa and in the mucus; and score C, H pylori solely in the mucus.

RESULTS

CagA antibodies were present in 154 (52.5%) of the patients. There was no significant difference in colonisation density and cagA status: grade I, 23 (14%); grade II, 78 (50.6%); grade III, 42 (27.5%); and grade IV, 11 (7.2%) in the cagA(+) strains and 29 (21.2%), 57 (40.8%), 38 (27%), and 15 (11%), respectively, in the cagA(-) strains. There was no difference in topographic localisation between cagA(+) and cagA(-)H pylori. Mean anti-CagA titres were 0.84, 0.84, 0.89, and 0.73 in patients with grades I-IV bacterial density, respectively.

CONCLUSION

Antibody titres do not correlate with H pylori density and there is no difference in density between cagA(+) and cagA(-)H pylori strains. In addition there is no difference in topographic localisation between cagA(+) and cagA(-) H pylori strains.