Chronic sinusitis (pyometra) generally develops when a cold causes a bacterial infection in the sinuses.In recent years, intractable chronic sinusitis with characteristics called type 2 inflammation has increased.Many nasal polyps occur in the nose, resulting in nasal congestion and loss of sense of smell.A large number of white blood cells called eosinophils are found, and it has become a designated intractable disease called eosinophilic sinusitis.The pathophysiology is unknown, and basic research as well as research on new treatments are desired.

　The research group conducted research on the pathogenesis of eosinophilic sinusitis, an immune disease, focusing on the relationship between the environmental factors and the resident bacterial flora (microbiome) that coexists with humans.

　The results suggested that the microbiomes of eosinophilic and non-eosinophilic sinusitis are different.In addition, eosinophilic sinusitis has a different bacterial composition from non-eosinophilic sinusitis, with a decrease in certain bacterial species, and in particular, the decrease in Fusobacterium nucleatum is the greatest. It was remarkable.They discovered that one of the causes was a decrease in lipopolysaccharide (LPS) produced by the bacteria, and further confirmed that LPS suppressed type 2 inflammation.

　This research has shown that intractable sinusitis (eosinophilic sinusitis) may develop due to changes in the bacterial species and their metabolites that make up the nasal microbiome.In the future, they hope to verify the effectiveness of improving the nasal microbiome in treating eosinophilic sinusitis, which will lead to lifestyle prevention and the development of new treatments such as probiotics.

Paper information:【The Journal of Allergy and Clinical Immunology】Middle meatus microbiome in patients with eosinophilic chronic rhinosinusitis in a Japanese population