Characteristics of airway hyperresponsiveness in children with chest tightness variant asthma / 中华实用儿科临床杂志

ABSTRACT

Objective To analyze the characteristics of airway hyperresponsiveness and fractional exhaled ni-tric oxide (FeNO)in children with chest tightness variant asthma (CTVA)in comparison with cough variant asthma (CVA)and the typical asthma. Methods From January 2012 to June 2015,37 atypical asthma children with chest tightness as the sole presenting manifestation were selected as subjects (CTVA group). Meanwhile,100 children who were newly diagnosed as CVA and 100 children who were newly diagnosed as typical asthma were selected as control group. All of the children in 3 groups had completed FeNO measurement,spirometry and with either positive result of bronchial provocation test or positive result of bronchial dilation test. The differences in FeNO and spirometry data among 3 groups were analyzed. Results FeNO was 11. 0(6. 0,33. 0)ppb in CTVA group,but 28. 0(16. 0,52. 0) ppb in typical asthma group,which indicated that FeNO was significantly lower in CTVA group than that in typical asth-ma group (P < 0. 05). The accumulated provocative dose of methacholine resulted in a 20％ (PD20-FEV 1 )drop in forced expiratory volume in 1 second (FEV 1 ),which was 0. 480(0. 145,0. 663)mg in CTVA group and 0. 180 (0. 097, 0. 463)mg in typical asthma group. PD20-FEV 1 was significantly higher in CTVA group than that in typical asthma group,and the difference was statistically significant(P < 0. 05). FeNO was 18. 5(8. 0,34. 0)ppb and PD20-FEV 1 was 0. 330(0. 120,0. 730)mg in CVA group,which had no statistically significant differences between CTVA group and CVA group(all P > 0. 05). Conclusion CTVA children have lower airway hyperresponsiveness and lower FeNO than typical asthma children. CTVA children may have similar airway hyperresponsiveness as CVA children.