The clinical use of urinary eosinophil protein X (U-EPX) measurements in monitoring inflammation in childhood asthma was investigated. U-EPX and pulmonary function were assessed in 80 children with bronchial asthma and 24 healthy, age-matched controls. In addition, 14 patients with asthma were re-examined after 1-2 months. U-EPX levels were increased in children with asthma compared with controls (median 68.4 vs 35.3 micrograms/mmol creatinine; P < 0.0001). In addition, U-EPX levels were higher in symptomatic than in asymptomatic patients (median 123.5 vs 48.9 micrograms/mmol creatinine; P < 0.0001) independent of treatment modalities (i.e., inhaled steroids or disodium cromoglycate) or atopy (median 65.1 vs 86.0 micrograms/mmol creatinine). Furthermore, U-EPX levels were significantly correlated with pulmonary function. During the follow-up period, changes in U-EPX values were significantly related to changes in pulmonary function. In conclusion, our findings demonstrate that eosinophil activation can be measured in urine in childhood asthma. Concentrations of U-EPX are related to disease activity and pulmonary function, as shown in both cross-sectional and longitudinal analyses, but are independent of atopy and treatment modalities. Measurement of U-EPX may be useful in assessing the inflammatory process and therefore in the management of childhood asthma.
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.