Helicobacter pylori treatment and antibiotic susceptibility: results of a five-year audit

Background: Helicobacter pylori eradication treatment has been a rapidly ev olving field. Audit of treatment results provides reassurance that trial da ta can be translated into routine clinical practice. Methods: Data were collected prospectively over five years. Patients were g iven four different treatment regimens over the audit period 'standard' tri ple therapy, two types of clarithromycin-based treatment or ranitidine, amo xycillin and metronidazole. Eradication was proven by a urea breath test at least four weeks after completing treatment. Results: Eradication treatment for H. pylori was given to 665 patients; 89% had follow-up data. N. pylori eradication was significantly associated wit h treatment type (p < 0.0001) and smoking (p = 0.04) by univariate analysis , but was not associated with sex, age, alcohol consumption, endoscopic dia gnosis, recent treatment with anti-secretory drugs or NSAIDs. By logistic r egression analysis, only treatment type was significant (p = 0.0001). H. py lori culture and sensitivities were available for 255 patients. Metronidazo le resistance was shown for 84 isolates (32%) and clarithromycin resistance for 18 isolates (6.8%). Metronidazole resistance was significantly associa ted with younger age (p = 0.02), ethnicity (p = 0.02), female sex (p = 0.02 ), and year of endoscopy (p = 0.04), but was not associated with clarithrom ycin resistance. Clarithromycin resistance was not associated with age, sex , or ethnicity. Metronidazole resistance significantly affected H. pylori e radication for regimens containing metronidazole without clarithromycin. Er adication with metronidazole without clarithromycin was achieved in 90% of sensitive strains but only 55% of resistant strains (p < 0.001). Metronidaz ole resistance was not significantly associated with treatment: failure whe n metronidazole was combined with clarithromycin. Eradication with metronid azole and clarithromycin was achieved in 86% of sensitive strains and 78% o f resistant strains (p = 0.42). Conclusion: Treatment type and antibiotic susceptibility are the most impor tant determinants of treatment success.