Treatment Outcomes with Empirical Clarithromycin-Based Triple Therapy for Helicobacter pylori in Zambia, Sub-Saharan Africa

INTRODUCTION: Helicobacter pylori (H. pylori) infection is highly prevalent in Zambia, with an estimated population prevalence of 79%. However, data on eradication treatment outcomes in routine clinical practice are lacking. METHODS: We conducted a single-arm cohort study in Lusaka, Zambia, to evaluate the effectiveness of empirical H. pylori eradication therapy using stool antigen testing (SAT). Symptomatic patients with confirmed H. pylori infection were treated empirically with clarithromycin-, tinidazole-, and omeprazole-based regimens. Eradication was assessed using SAT at least 4 weeks after completion of therapy. Demographic and clinical factors associated with treatment outcomes were analysed using multivariate logistic regression in Stata version 15. RESULTS: Of 331 patients tested, 216 (65%) were positive for H. pylori infection. Post-treatment SAT results were available for 139 (64%) patients, of whom 93 (67%) were female. The median age was 43 years (interquartile range: 36-54). Overall, eradication was achieved in 85 patients, yielding a treatment success rate of 61%. Multivariate analysis demonstrated that a history of prior eradication attempts (odds ratio [OR]: 0.20, 95% confidence interval [CI]: 0.04-0.60) was independently associated with treatment failure. In contrast, the occurrence of dysgeusia during therapy (OR: 3.20, 95% CI: 1.20-8.70) and prior proton pump inhibitor use (OR: 5.30, 95% CI: 1.40-19.80) were associated with higher odds of eradication. CONCLUSION: The effectiveness of empirical clarithromycin-based therapy for H. pylori infection in Zambia is suboptimal and falls below internationally recommended targets. These findings underscore the need to reassess empirical treatment strategies, particularly among patients with previous eradication attempts, and highlight the importance of locally informed antibiotic selection.