Mechanism of action of the sinus microbiome in postoperative recurrence of type 2 chronic rhinosinusitis and advances in targeted intervention.

The repetition of a condition following endoscopic sinus surgery (ESS) poses an important difficulty in type 2 chronic rhinosinusitis with nasal polyps (CRSwNP) therapy. The recurrent nature of the disease is probably linked to the dynamic interplay of the enduring type 2 inflammatory microenvironment and the imbalanced sinonasal microbiome. The microbiomic characteristics and pathogenic mechanisms of postoperative recurrence are systematically elaborated in this paper, indicating that recurrent CRSwNP is characterized by microbial dysbiosis featured by enrichment of Staphylococcus aureus, depletion of Corynebacterium, and reduction in α-diversity. Its core mechanisms involve superantigen-mediated immune hijacking, epithelial barrier collapse caused by microbial metabolic imbalance, and physiological tolerance mediated by biofilms. On this basis, as a scoping review, this paper further reviews the shift of intervention strategies from "broad-spectrum bactericidal" to "precise ecological restoration", including narrow-spectrum antibacterial and phage therapies targeting Staphylococcus aureus, ecological replacement therapy by supplementing nasal-specific commensal bacteria (such as Corynebacterium), and synergistic regulation strategies using biological agents such as dupilumab to indirectly reshape the microecology by inhibiting type 2 inflammation. In addition, the paper also discusses the potential of constructing postoperative recurrence prediction models based on microbial biomarkers, aiming to provide a theoretical basis for the precise and dynamic management of CRSwNP.