Diagnostic value and underlying mechanism of nasal nitric oxide in eosinophilic chronic rhinosinusitis with nasal polyps

Predictive Value of Nasal Nitric Oxide for Diagnosing Eosinophilic Chronic Rhinosinusitis: A Systematic Review and Meta-Analysis

OBJECTIVES

The primary aim of this study was to assess disparities in nasal nitric oxide (NO) levels between individuals diagnosed with eosinophilic chronic rhinosinusitis (ECRS) and those without ECRS. The second aim was to ascertain the comparative predictive efficacy of these nasal NO levels for the presence of ECRS.

METHODS

A systematic analysis was conducted on relevant studies that compared nasal NO levels in individuals with ECRS and those without. Furthermore, the discriminatory capacity of nasal NO in distinguishing ECRS from non-ECRS cohorts was quantified. The risk of bias across studies was evaluated utilizing the Newcastle-Ottawa scale.

RESULTS

The comprehensive review encompassed a total of 5 studies involving 470 participants. Findings revealed that patients diagnosed with ECRS exhibited significantly higher levels of nasal NO, as measured in parts per billion (ppb), compared to their non-ECRS patients. The mean difference was 130.03 ppb (95% confidence interval: [66.30, 193.75], I2 = 58.7%). The diagnostic odds ratio for nasal NO in identifying ECRS was 9.29 ([5.85, 14.75], I2 = 26.4%). The area under the summary receiver operating characteristic curve was 0.82. The correlation between sensitivity and false positive rate was 0.53, suggesting a lack of heterogeneity. Sensitivity, specificity, negative predictive value, and positive predictive value were 69% ([0.55, 0.79], I2 = 77.0%), 83% ([0.73, 0.90], I2 = 68.5%), 77% ([0.69, 0.83], I2 = 50.1%), and 75% ([0.67, 0.82], I2 = 41.5%), respectively.

CONCLUSION

Nasal NO has the potential as a noninvasive diagnostic measure and endotype tool for ECRS.

Skin, gut, and lung barrier: Physiological interface and target of intervention for preventing and treating allergic diseases

The epithelial barriers of the skin, gut, and respiratory tract are critical interfaces between the environment and the host, and they orchestrate both homeostatic and pathogenic immune responses. The mechanisms underlying epithelial barrier dysfunction in allergic and inflammatory conditions, such as atopic dermatitis, food allergy, eosinophilic oesophagitis, allergic rhinitis, chronic rhinosinusitis, and asthma, are complex and influenced by the exposome, microbiome, individual genetics, and epigenetics. Here, we review the role of the epithelial barriers of the skin, digestive tract, and airways in maintaining homeostasis, how they influence the occurrence and progression of allergic and inflammatory conditions, how current treatments target the epithelium to improve symptoms of these disorders, and what the unmet needs are in the identification and treatment of epithelial disorders.

Updated epithelial barrier dysfunction in chronic rhinosinusitis: Targeting pathophysiology and treatment response of tight junctions

Tight junction (TJ) proteins establish a physical barrier between epithelial cells, playing a crucial role in maintaining tissue homeostasis by safeguarding host tissues against pathogens, allergens, antigens, irritants, etc. Recently, an increasing number of studies have demonstrated that abnormal expression of TJs plays an essential role in the development and progression of inflammatory airway diseases, including chronic obstructive pulmonary disease, asthma, allergic rhinitis, and chronic rhinosinusitis (CRS) with or without nasal polyps. Among them, CRS with nasal polyps is a prevalent chronic inflammatory disease that affects the nasal cavity and paranasal sinuses, leading to a poor prognosis and significantly impacting patients' quality of life. Its pathogenesis primarily involves dysfunction of the nasal epithelial barrier, impaired mucociliary clearance, disordered immune response, and excessive tissue remodeling. Numerous studies have elucidated the pivotal role of TJs in both the pathogenesis and response to traditional therapies in CRS. We therefore to review and discuss potential factors contributing to impair and repair of TJs in the nasal epithelium based on their structure, function, and formation process.

Influence of pallet rich plasma, quercetin and their combination on activity of nitric oxide cycle enzymes in nasal mucosa of patients with atrophic rhinitis

OBJECTIVE

Aim: To study the general activity of NO synthases (gNOS), the activity of inducible and constitutive isoforms of NO synthase, the activity of arginases, and the concentration of nitrites in the nasal mucosa under the conditions of local treatment of chronic atrophic rhinitis (AR) with quercetin and platelet-rich plasma (PRP therapy)..

PATIENTS AND METHODS

Materials and Methods: The study was conducted on 118 patients divided into two groups: control (n=20) and experimental (patients with AR, n=98). Experimental group was divided into 4 subgroups: standard treatment (n=29), PRP therapy (6 injections for 28 day course, n=19), Quercetin (40 mg 3 times a day for 28 days, n=26) and PRP+Quercetin (n=24) groups.

RESULTS

Results: Standard therapy of SaR increases gNOS by 278.38% and arginase activity increases by 222.73%. PRP therapy increases gNOS by 211.43% and arginase by 540.91%. Quercetin elevates gNOS by 108.33% and arginase by 250%. PRP therapy and quercetin increases gNOS by 146.15% and arginase by 536.36%.

CONCLUSION

Conclusions: The use of standard therapy of SaR and addition of PRP therapy, quercetin and their combination effectively restores the production of nitric oxide and the arginase activity in the nasal mucosa.