The Effects of Antibiotics for Helicobacter pylori Eradication or Dapsone on Chronic Spontaneous Urticaria: A Systematic Review and Meta-Analysis.

Background: Chronic spontaneous urticaria (CSU) is a disease with wheals and/or angioedema. Some drugs, especially antibiotics for Helicobacter pylori (H. pylori) eradication and the sulfone antibiotic dapsone, may be candidates for treating CSU. The present study assessed the efficacy of these antibiotic therapies for CSU. Methods: Databases (MEDLINE, the Cochrane Central Register of Controlled Trials, EMBASE, the World Health Organization International Clinical Trials Platform Search Portal and ClinicalTrials.gov) were searched until October 2020. Study selection, data abstraction and quality assessments were independently performed using the Grading of Recommendations Assessment, Development and Evaluation approach. The outcomes were the remission of CSU-related symptoms, activities and adverse events due to antibiotics for H. pylori eradication or dapsone. Results: Nine randomized controlled trials (RCTs; 361 patients) were included. The antibiotics for H. pylori eradication increased the remission rate (risk ratio (RR) = 3.99, 95% confidence interval (CI) = 1.31 to 12.14; I2 = 0%), but dapsone did not (RR = 1.15, 95% CI = 0.74 to 1.78). Antibiotics for H. pylori eradication (standard mean difference (SMD) = 1.49, 95% CI = 0.80 to 2.18; I2 = 69%) and dapsone (SMD = 7.00, 95% CI = 6.92 to 7.08; I2 = 0%) improved symptoms. The evidence of certainty was moderate. Dapsone was associated with mild adverse events, whereas H. pylori eradication was not. Conclusion: Antibiotics, especially those for H. pylori eradication, improved the remission rate and symptoms of CSU with few adverse events. Further studies are needed.