Background: In adults, measurement of F E NO has been recently suggested as a substitute for the methacholine challenge test (MCT) for diagnosis of asthma. This study aimed to evaluate whether FeNO is a substitute for MCH also in children with suspicious asthma. Methods: During a single visit steroid naive children (5-17 years) with suspicious asthma underwent skin prick test (SPT), F E NO measurement and spirometry prior and during MCT (one concentration procedure). Results of the SPT (atopy/non-atopy) and MCT (asthma/non-asthma) were used for categorization. ROC analysis in atopy non-atopy subgroups yielded sensitivity, specificity, positive and negative predictive value (PPV and NPV) for F E NO. Results: The SPT revealed atopy in 134 out of 222 children (age 9.7 ± 3.2 years) investigated and asthma was diagnosed in 114 (77/37 atopy/non-atopy) patients. F E NO values in patients with atopic asthma were significantly higher compared to those with either non-atopic asthma or atopia without asthma (18 ppb (5-89) vs 7 ppb (5-36); p < 0.001; 18 ppb (5-89) vs 11 ppb (5-98); p < 0.05). Sensitivity and specificity of F E NO for diagnosing atopic asthma (F E NO≥15.5 ppb; AUC = 0.635, p < 0.01) were 61.1% and 64.9% and non-atopic asthma (F E NO≥ 6.5 ppb; AUC = 0.445, p = 0.382) 54.1% and 39.2%, respectively. The PPV/NPV for F E NO were 0.70/0.55 in atopy and 0.39/0.54 in non-atopy patients, respectively. Conclusion: In children, F E NO is not appropriate to substitute for the MCT. However, in patients with a negative SPT a F E NO in the normal range makes the presence of atopic asthma unlikely.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.