Prevalence and factors associated with web‑like mucus in the stomach after vonoprazan use

The appearance of 'web-like mucus' in the stomach is a novel phenomenon associated with vonoprazan (VPZ) usage, characterized by a descriptive mucus pattern resembling a spider web or net. The present study aimed to determine its prevalence and related factors. In this retrospective observational study, the medical records and endoscopic reports of 547 patients who underwent an esophagogastroduodenoscopy were reviewed. The overall prevalence of web-like mucus was 6% (33/547), with 97% (32/33) of these patients being VPZ users. Specifically, 19% (32/167) of VPZ users exhibited this web-like mucus pattern, which was significantly more prevalent in the VPZ group than in the control (no acid blocker intake), proton pump inhibitor, and histamine-2 receptor antagonist groups. Multivariate analysis identified that VPZ use was positively associated with web-like mucus, while open-type gastric atrophy and multiple white and flat elevated lesions were negatively associated. A retrospective analysis of endoscopic findings before initiating VPZ therapy showed that none of the 32 VPZ users with web-like mucus had exhibited the pattern previously. Furthermore, the Cochran-Armitage trend test indicated no significant association between the duration of VPZ therapy and the prevalence of web-like mucus. In conclusion, web-like mucus in the stomach is strongly associated with VPZ use but is not associated with the duration of VPZ therapy.