Spider Web-like mucus pattern after vonoprazan usage- What contributes to its formation?

The increasing prevalence of gastroesophageal reflux disease led to the use of acid blockers like vonoprazan (VPZ) and proton pump inhibitors (PPIs). Vonoprazan is a potassium-competitive acid blocker (PCAB) that reversibly inhibits gastric acid output through K+-competitive ionic binding to H+/K+-ATPase. There was a steady increase in the prescription of this drug owing to its effectiveness in treating reflux esophagitis, eradicating Helicobacter pylori (HP), treating gastric and duodenal ulcers, and even treating post-endoscopic submucosal dissection ulcers. Literature has shown that web-like mucus patterns develop in the stomach when vonoprazan (VPZ) is used. Hence, researchers from Jichi Medical University, Japan studied the prevalence and associated factors of web-like mucus in the stomach with vonoprazan (VPZ) usage.

A retrospective observational study was carried out on the medical records and endoscopic reports of 547 patients who underwent an esophagogastroduodenoscopy. Ultra-thin endoscopy recorded acid blocker use, gastric atrophy grading, and gastric abnormalities, including web-like mucus. Web-like mucus is a solid adhesion resistant to washing that is observed in endoscopic findings.

Findings:

• The overall prevalence of web-like mucus was 6% (33/547), with 97% (32/33) of these patients being VPZ users.
• About 19% (32/167) of VPZ users developed web-like mucus patterns.
• The web-like pattern was more significantly seen in the VPZ group than in the control (no acid blocker intake), proton pump inhibitor, and histamine-2 receptor antagonist groups.
• As per the multivariate analysis, VPZ 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 the previous endoscopic findings showed that a web-like mucus pattern was not seen previously in the 32 VPZ users who had initiated VPZ therapy.
• In the Cochran-Armitage trend test, no significant association was found between VPZ therapy duration and web-like mucus prevalence.

Thus, the researchers concluded that web-like mucus in the stomach is strongly associated with VPZ use but not with the duration of VPZ therapy. This unique web-like pattern is the potential endoscopic diagnostic marker and helps differentiate VPZ-induced gastric changes from other conditions.

Further reading: Shinozaki, Satoshi et al. “Prevalence and factors associated with web‑like mucus in the stomach after vonoprazan use.” Biomedical reports vol. 22,2 33. 10 Dec. 2024, doi:10.3892/br.2024.1911.