ABSTRACT
OBJECTIVES/HYPOTHESIS: The aim of this study was to evaluate the associations between nasal nitric oxide and nasal symptoms, sinus opacification, and markers of allergic inflammation in allergic and in nonallergic rhinitis while taking into account the effect of sinus obstruction. STUDY DESIGN: We studied 175 young adult subjects divided into three groups: 1) allergic rhinitis, 2) nonallergic rhinitis, and 3) controls. METHODS: We measured nasal nitric oxide using the breath-holding method and exhaled nitric oxide and scored semiquantitatively nasal computed tomography scans for opacification and obstruction. We also assessed the visual analogue scores of nasal symptoms, eosinophil count, and interleukin-13 mRNA levels in nasal biopsies. RESULTS: The level of nasal nitric oxide correlated with exhaled nitric oxide (r = 0.377, P < .001). In allergic rhinitis, nasal nitric oxide was elevated when compared to the controls, and an inverse correlation existed between the nasal nitric oxide level and sinus ostial obstruction (r = -0.272, P = .013). In nonallergic rhinitis, the level of nasal nitric oxide was similar to that of the controls. In allergic rhinitis, nasal nitric oxide correlated positively with the opacification score (r = 0.250, P = .033) and the nasal eosinophil count (r = 0.293, P = .030) of patients without a marked sinus ostial obstruction. CONCLUSIONS: Sinus ostial obstruction lowers the level of nasal nitric oxide and reduces its value as an indicator of allergic mucosal inflammation. A high nasal nitric oxide level may be a useful marker of eosinophilic inflammation in the nasal cavity and indicate the absence of marked sinus ostial obstruction. LEVEL OF EVIDENCE: 3b.
Subject(s)
Nasal Obstruction/physiopathology , Nitric Oxide/pharmacokinetics , Rhinitis, Allergic, Perennial/diagnosis , Adult , Age Factors , Biomarkers/metabolism , Breath Tests , Case-Control Studies , Exhalation/physiology , Female , Follow-Up Studies , Humans , Incidence , Male , Multivariate Analysis , Nasal Obstruction/epidemiology , Nasal Obstruction/metabolism , Reference Values , Rhinitis, Allergic , Rhinitis, Allergic, Perennial/epidemiology , Rhinitis, Allergic, Perennial/physiopathology , Risk Assessment , Sensitivity and Specificity , Severity of Illness Index , Sex Factors , Young AdultABSTRACT
BACKGROUND: Rhinitis and asthma commonly coexist and are often regarded as "unified airways disease." Evidence exists that microRNAs are important in controlling inflammatory processes, but little is known about their role in airway inflammation. The present study evaluated the inflammatory profiles of patients with allergic rhinitis (AR), with and without concomitant asthma, and of patients with nonallergic rhinitis (NAR). METHODS: We analyzed inflammatory cells, cytokines, and microRNAs from nasal biopsies and measured nasal nitric oxide (nNO) levels in 159 young adult subjects subdivided into 4 groups: (1) AR; (2) AR+asthma; (3) NAR; and (4) controls. RESULTS: We observed the upregulation of T-helper 2 (Th2) cytokines and the trend of elevation of nNO levels in AR patients compared to controls. Subjects with current AR symptoms had increased levels of miR-155, miR-205, and miR-498, but reduced levels of let-7e. In addition, patients with positive skin prick test (SPT) reactions exhibited increased miR-155 and miR-205 expression and a decreased level of let-7e, compared to subjects with negative SPT findings. Concomitant asthma had little effect on the inflammatory profile of AR. No significant changes in inflammatory markers were found in NAR patients compared to healthy controls. CONCLUSION: Our results suggest that microRNAs miR-155, miR-205, miR-498, and let-7e may be important in the allergic inflammation present in nasal mucosa. Regarding NAR, our findings support the view that mechanisms other than inflammation are pivotal.
