Like other countries in the world, Japan has witnessed a worrisome increase in the prevalence of chronic rhinosinusitis (CRS) over the last decade. An inflammatory disease that lasts at least 12 weeks, CRS can cause nasal congestion, nasal discharge, trouble breathing through the nose, facial pain, and even loss of sense of smell. Unfortunately, treating CRS is complex since the disease manifests in various forms. CRS can be categorized into eosinophilic (ECRS) or non-eosinophilic (non-ECRS) types. In ECRS, the nasal and sinus tissues exhibit an increased presence of eosinophils, a type of white blood cell that releases inflammatory compounds.
The increased prevalence of CRS is largely driven by environmental factors that are in turn impacted by lifestyle changes. Of the several environmental factors, microorganisms residing in the nasal cavity and passages have been known to substantially affect our health. It is however, unclear whether the nasal microbiome contributes to the development of ECRS.
To address this knowledge gap, a research team from Japan led by Assistant Professor Masanori Kidoguchi from the Faculty of Medical Science of the University of Fukui, Japan, recently conducted a study on CRS in a Japanese population with a focus on the nasal microbiome. Their paper, which was also co-authored by Professor Shigeharu Fujieda from the University of Fukui and Professor Emiko Noguchi from the University of Tsukuba, was published in The Journal of Allergy and Clinical Immunology on September 25, 2023. Dr. Kidoguchi remarks, “We undertook this study because the pathological functions of bacteria