PurposeNasal Cellulose Powder (NCP), which can prevent from binding an allergen to nasal mucosa, may reduce allergic rhinitis (AR) symptoms in dust mite-sensitized children. This study was conducted to assess the efficacy of NCP in improving clinical symptoms of a nasal airflow limitation and the response of nasal inflammatory cells.MethodsChildren with dust mite-sensitized AR aged 6-18 years were recruited. After a 4-week run-in period, NCP or a placebo was administered, 1 puff per nostril 3 times daily for 4 weeks. The nasal provocation test (NPT) with Dermatophagoides pteronyssinus (Der p) was performed before and after treatment. The daily symptom scores (DSS), daily medication scores (DMS), the peak nasal inspiratory flows (PNIF), nasal airway resistance (NAR), as well as the maximum tolerated dose of NPT and eosinophil counts in nasal scraping, were evaluated.ResultsSixty children (30 NCP and 30 placebos) were enrolled. Before treatment, there were no significant differences in age, dust mite control measures, DSS, DMS, PNIF, NAR, the maximum tolerated dose of NPT, or nasal eosinophil scores between children receiving NCP and placebos. After treatment, there were no significant differences between the NCP and placebo groups in the median (range) of the outcomes—DSS: 2.06 (0.18-3.77) vs 1.79 (0.08-7.79), P=0.756; DMS: 1.60 (0-5.13) vs 0.56 (0-4.84), P=0.239; PNIF (L/min): 110 (60-160) vs 100 (50-180), P=0.870; NAR (Pa/cm3/s): 0.40 (0.20-0.97) vs 0.39 (0.24-1.32), P=0.690; the maximum tolerated dose of NPT and the nasal eosinophil scores: 1 (0-4) vs 1 (0-4), P=0.861.ConclusionsNCP treatment may not be more effective than placebo treatment in dust mite-sensitized AR children.

Background Rhinitis is a common problem in children. Airway nitric oxide (NO) was proposed to represent eosinophilic inflammation. Objectives To evaluate airway NO level in children with house dust mite (HDM)-induced allergic rhinitis Methods Children aged 5 to 18 years old with moderate–severe persistent rhinitis and positive result for the HDM nasal provocation test (NPT) was enrolled. The nasal symptoms evaluated by total nasal symptom score (TNSS) and visual analog scale (VAS) were recorded. Skin prick test (SPT) to common aeroallergens, fractional exhaled nitric oxide (FeNO), nasal nitric oxide (nNO), and blood test for specific IgE (sIgE) to HDM was measured. Rhinitis severity was categorized as severe if the VAS score > 7. Results Forty-eight children with HDM-induced allergic rhinitis with the mean age of 9.3 ± 2.4 years were enrolled. nNO levels and VAS score were significantly correlated (R = 0.398, P = .005). Children with severe rhinitis had significantly higher nNO levels than moderate rhinitis (1652.05 vs 941.30 parts per billion [ppb], P = .002), while there was no difference in FeNO level. ROC curve analysis demonstrated the cut-off value of nNO at 1350 ppb (AUC 0.764, 95% CI: 0.616-0.911, P = .002) for detecting severe HDM-induced allergic rhinitis with the sensitivity of 78% and the specificity of 71%. The level of FeNO in children who had HDM mean wheal diameter (MWD) > 8 mm was significantly higher than those with HDM MWD of 3 to 8 mm and those with a negative test (39.7 vs 14.3 vs 14.4 ppb; P = .006, respectively). Children who had sIgE to HDM < 0.35 KUA/L had significantly lower FeNO than those with sIgE to HDM 0.35 to 50 KUA/L and >50 KUA/L (9.5 vs 19.7 vs 40.4 ppb; P = .029, respectively). Conclusions Cut-off value for the diagnosis of severe HDM-induced chronic rhinitis was proposed. Rhinitis children who had a higher degree of HDM sensitization had a higher level of FeNO.

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