Type 2 and Non-type 2 Inflammation in the Upper Airways: Cellular and Molecular Alterations in Olfactory Neuroepithelium Cell Populations.

PURPOSE OF REVIEW: Neurogenesis occurring in the olfactory epithelium is critical to continuously replace olfactory neurons to maintain olfactory function, but is impaired during chronic type 2 and non-type 2 inflammation of the upper airways. In this review, we describe the neurobiology of olfaction and the olfactory alterations in chronic rhinosinusitis with nasal polyps (type 2 inflammation) and post-viral acute rhinosinusitis (non-type 2 inflammation), highlighting the role of immune response attenuating olfactory neurogenesis as a possibly mechanism for the loss of smell in these diseases. RECENT FINDINGS: Several studies have provided relevant insights into the role of basal stem cells as direct participants in the progression of chronic inflammation identifying a functional switch away from a neuro-regenerative phenotype to one contributing to immune defense, a process that induces a deficient replacement of olfactory neurons. The interaction between olfactory stem cells and immune system might critically underlie ongoing loss of smell in type 2 and non-type 2 inflammatory upper airway diseases. In this review, we describe the neurobiology of olfaction and the olfactory alterations in type 2 and non-type 2 inflammatory upper airway diseases, highlighting the role of immune response attenuating olfactory neurogenesis, as a possibly mechanism for the lack of loss of smell recovery.

Quality of Life in Symptomatic Septal Perforation.

OBJECTIVE: The aim of this study is to investigate the impact of septal perforation (SP) on quality of life (QoL). SP is compared to the general population and patients with chronic rhinosinusitis with nasal polyposis (CRSwNP) using the Sino-Nasal Outcome Test 22 (SNOT-22). METHODS: Prospective single-center study in a referral Rhinology Unit from January 2014 to March 2023. RESULTS: A total of 392 patients were included in three groups: controls (n = 141), CRSwNP (n = 118), and SP (n = 133). The mean score of the SNOT-22 was significantly higher in the CRSwNP group (42.4, SD = 24.4) and SP (46.5, SD = 22) compared to the control group (6.2, SD = 8.4). Scores by either items or domains were significantly higher in the CRSwNP and SP groups compared to the control group. There were no significant differences in the mean SNOT-22 between the CRSwNP and SP groups (p = 0.26; 95% CI -1.68-9.99). Domain-specific analysis of overall SNOT-22 scores revealed that patients with SP experienced higher levels of disturbances in sleep, function, and psychological domains (p ≤ 0.001). CONCLUSION: SP produces a negative impact on QoL similar to CRSwNP. Moreover, sleep, psychological, and function domains are significantly worse in SP. Etiology and area of SP influence nasal and emotion domain, though more studies on SP using SNOT-22 and specific questionnaires are needed. LEVEL OF EVIDENCE: Level III Laryngoscope, 2024.