Can microbial profiles influence type II inflammation in chronic rhinosinusitis with nasal polyps?

This study aimed to assess how different treatments - dupilumab vs surgery - influence the nasal microbiota, type 2 inflammation, and clinical outcomes in CRSwNP patients.

This was a prospective observational study of 44 CRSwNP patients assigned to 6 months of biweekly dupilumab injections or functional endoscopic sinus surgery (FESS). Nasal microbiotas were analyzed at baseline and 6 months using culture techniques. Inflammatory biomarkers (IgE, eosinophils) and clinical endpoints (polyp score, SNOT-22, smell test) were measured. Patients were also stratified into groups based on which bacteria were cultured from their sinuses.

At baseline, the most prevalent bacteria were Staphylococcus aureus (43%), Stapylococcus epidermidis (36%), and Pseudomonas aeruginosa (16%). After 6 months, S. aureus and S. epidermidis significantly increased while P. aeruginosa decreased. Eosinophil counts were stable. IgE levels notably decreased in the S. aureus and S. epidermidis groups but increased with P. aeruginosa. All bacterial groups showed reduced polyp score and SNOT-22, and improved smell, but P. aeruginosa had smaller gains. Higher baseline S. aureus and S. epidermidis correlated with more significant IgE decrease.

Dupilumab and surgery-induced favourable microbiota changes by reducing pathogenic bacteria. Nasal microbiota composition may be associated inflammatory and clinical treatment responses in CRSwNP. S. aureus and S. epidermidis correlated with a greater improvement of IgE levels, whereas P. aeruginosa correlated with worse IgE outcomes. Analyzing each patient's nasal microbiome could enable more personalized, microbiome-directed treatment approaches for optimal CRSwNP management.