IHC positive area analysis corroborated these findings, with elevated MUC5AC levels in CRSwNP (WMD: 25.61; 95% CI: 22.41–28.81) and CRSsNP (WMD: 39.74; 95% CI: 25.6–53.88) patients. Here, MUC5AC is linked to chronic rhinosinusitis without nasal polyps.