Anti Helicobacter pylori IgG and IgA response in patients with gastric cancer and chronic gastritis

BACKGROUND/AIMS

Immune response against Helicobacter pylori is important for the course and outcome of infection. We conducted study looking for the difference in anti H. pylori IgG and IgA between patients with intestinal type of gastric cancer, superficial and atrophic gastritis.

METHODOLOGY

For this study, 133 patients infected with H. pylori were enrolled: 50 with superficial gastritis, 42 with atrophic gastritis and 41 with gastric cancer. Anti H. pylori IgG and IgA ELISA tests were performed. The difference in antibody titers of IgG and IgA, frequency of IgA > IgG ratio and combination of low IgG and IgA > IgG ratio were analyzed.

RESULTS

The patients with gastritis had higher titer of IgG that the patients with gastric cancer (p < 0.01). The patients with superficial gastritis had higher titer of IgA than the patients with gastric cancer (p < 0.05). IgA > IgG ratio is more frequent in patients with gastric cancer than in the patients with superficial gastritis (p < 0.01). Low IgG and IgA > IgG is more frequent in the patients with gastric cancer than in the patients with gastritis (p < 0.01).

CONCLUSIONS

The patients with gastric cancer elicit different anti H. pylori IgG and IgA response than the patients with superficial and atrophic gastritis. Low IgG and IgA predominance seems characteristic for gastric cancer.

Systemic humoral anti-Helicobacter pylori immune response in patients with gastric malignancies and benign gastroduodenal disease

BACKGROUND/AIMS

Helicobacter pylori elicits a strong local and systemic humoral immune response, but it is not able to eliminate bacteria. Immune response may be important for the course of infection that may lead to different gastroduodenal disease. In order to investigate differences in systemic humoral immune response between patients with different gastroduodenal diseases, we conducted clinical and serological studies.

METHODOLOGY

From 1999 to 2001 we enrolled 80 patients with dyspeptic symptoms: 26 with gastritis, 12 with duodenal ulcer, 29 with gastric cancer and 13 with gastric lymphoma. In all patients during diagnostic work-up we performed ELISA test with Helicobacter pylori-specific IgG and IgA. We investigated difference in stimulation of different immunoglobulin classes in patients with different gastroduodenal diseases, particularly benign and malignant. We estimated significance of differences with Mann-Whitney and Fisher exact probability test.

RESULTS

All patients enrolled in the study were seropositive. Patients with gastritis had statistically significant higher level of IgG than patients with gastric cancer (p=0.0001), and gastric lymphoma (p=0.006). Patients with duodenal ulcer had statistically significant higher level of IgG than patients with gastric cancer (p=0.02), and gastric lymphoma (p=0.046). IgA level was significantly higher in patients with gastritis than in patients with gastric cancer (p=0.03). IgA>IgG ratio was significantly more frequent in patients with gastric cancer and gastric lymphoma than in patients with gastritis and duodenal ulcer (p=0.0002).

CONCLUSIONS

Result of our study suggested that Helicobacter pylori elicits different systemic humoral immune response in patients with gastritis and duodenal ulcer than in patients with gastric cancer and gastric lymphoma at least in intensity of stimulation of different immunoglobulin classes.