CLINICAL-APPLICATION OF GASTRIC HISTOLOGY TO MONITOR TREATMENT OF DUAL THERAPY IN HELICOBACTER-PYLORI ERADICATION

This preliminary study attempted to test whether pretreatment gastric histology of H. pylori infection may affect the success of dual therap y and to identify which parameter of gastric histology could be improv ed after dual therapy, One hundred forty-five dyspeptic patients with H. pylori infection received a two-week course of dual therapy (Amoxic illin 500 mg every 6 hr plus omeprazole 20 mg twice a day). In each pa tient, three pairs of gastric biopsies, sampled from the antrum, lower body, and upper body near the cardia, were collected before treatment and four weeks after completion of dual therapy. The density of H. py lori (score 1-5) and parameters of the modified Sydney system were app lied to test the severity of H. pylori-related gastric histology in ea ch specimen. The total bacterial load (score 1-15) was a sum of the de nsity of H. pylori sampled from three biopsies. The overall rate of H. pylori eradication rate by dual therapy is 73.1% (106/145). Univariat e analysis of parameters in pretreatment histology disclosed that the presence of mucosal atrophy (P < 0.01), lymphoid follicles (P < 0.005) , and higher-density H. pylori (P < 0.001) predisposed to dual therapy failure. Multivariate analysis by stepwise logistic regression furthe r confirmed that both the density of bacteria and the presence of lymp hoid follicles are the two major factors related to the outcome of dua l therapy (P < 0.001). Four weeks after dual therapy was completed, on ly patients with successful eradication significantly improved in thes e gastric histology parameters: acute activity, chronic inflammation, eosinophil infiltration, and mucosal atrophy. However, the lymphoid fo llicle and intestinal metaplasia were not significantly improved durin g the study period. The eradication rates among three subgroups with d ifferent total bacterial loads (group I: 1-5; II: 6-10; III: 11-15) di sclosed a downward trend (I: 89.1%; II: 73%; III: 52.7%). It is conclu ded that dual therapy could improve gastric histology especially among patients with successful eradication of H. pylori. Evaluating pretrea tment histologic parameters, including the density of H. pylori and th e presence of lymphoid follicles, is valuable in predicting the succes s of dual therapy.