To explore the possible value of fractional exhaled nitric oxide (FeNO)in the treatment of asthmatic children with montelukast.

Forty asthmatic children aged 5-14 were enrolled from May 2013 to May 2014 in the pediatrics department of the Shanghai Fifth People′s Hospital affiliated to Fudan University. Montelukast was administered to the enrolled patients for 12 weeks and each child was followed up for 6 times to detecte the levels of FeNO. The morning peak expiratory flow (PEF) was measured and the percentage of predicted PEF (PEF%pred) was calculated. The asthma control test of children (C-ACT) was recorded. According to the changes in the level of asthma control before and at the 12th week of treatment with montelukast, the enrolled patients were divided into the effective group and the noneffective group, and the clinical data were analyzed by SPSS 17.0.

Thirty-one children completed a 12 week study in the end, with 21 patients in the effective group and 10 in the noneffective group. The differences in asthma history(2.36±2.03, 3.60±1.51), disease grading(16/5, 1/9), initial C-ACT scores(20.71±0.85, 19.30±1.57), and initial FeNO level [(9.93±7.69)ppb, (32.52±22.70)ppb] were statistically significant between the two groups (t=1.72, χ²=11.98, t=3.29, t=4.15, all P<0.05). The starting FeNO level in the effective group was (9.93±7.69)ppb and there were no significant differences between the 6 measurements (F=0.51, P>0.05). The starting FeNO level in the noneffective group was (32.52±22.70)ppb and there were no significant differences between the 6 measurements (F=0.56, P>0.05) as well. The PEF%pred and C-ACT scores of the two groups after treatment with montelukast were improved, and the differences among the 6 measurements were statistically significant (F=4.63, 6.06, 50.67, 6.09, all P<0.05). There were no correlations between FeNO and PEF%pred, FeNO and C-ACT scores during the 12 weeks treatment of montelukast between the two groups (P>0.05) except that the FeNO level was positively correlated with PEF%pred at the second week in the effective group (r=0.44, P<0.05).

Compared with PEF%pred and C-ACT scores, FeNO level has no significant efficacy monitoring value. The history of asthmatic children, disease grading, initial C-ACT scores and initial FeNO level may affect the efficacy of montelukast.