Bismuth-containing quadruple therapy for Helicobacter pylori infection in penicillin‑allergic children: efficacy, safety and real‑world experience from China.

purposeTo assess the efficacy and safety of 14-day bismuth-containing quadruple therapy (BQT) as both first-line and rescue treatment for children with Helicobacter pylori infections and penicillin allergies in China.

methodsThis real-world, exploratory, retrospective observational cohort study enrolled children aged 6 to 18 years who underwent gastroendoscopy. The eradication status was assessed at least 4 weeks after treatment completion. A negative urea breath test or endoscopic rapid urease test result indicated successful eradication.

resultsBetween July 2017 and June 2025, 453 patients were analyzed in the study. Metronidazole-clarithromycin BQT as first-line treatment achieved eradication rates of 81.2% (285/351; 95% confidence interval [CI], 77.1-85.3%) and 82.5% (279/338; 95% CI, 78.5-86.6%) in modified intention-to-treat (mITT) and per-protocol (PP) analyses. Metronidazole-clarithromycin BQT as rescue therapy succeeded in 41.4% (41/99; 95% CI, 31.7-51.1%) of cases in mITT and in 42.6% (40/94; 95% CI, 32.6-52.5%) of cases in PP analyses. Three patients treated with metronidazole-minocycline BQT as rescue therapy all achieved successful eradication of H. pylori. Adverse effects were reported by 12.8% (45/351) of patients in the first-line therapy group and 9.8% (10/102) in the rescue therapy group (p = 0.40). The compliance rates for metronidazole-clarithromycin BQT as first-line therapy and rescue therapy were 96.3% (338/351) and 94.9% (94/99), respectively.

conclusionAs first-line therapy, metronidazole-clarithromycin BQT achieved an eradication rate of 82.5% in Chinese children with penicillin allergies. However, this regimen was inadequate as a rescue treatment. Rescue regimens such as those containing minocycline or cefuroxime warrant further investigation.