Can early asthma be confirmed by laboratory tests?

Abstract

We examined the performance of a number of laboratory tests in 23 patients who had had symptoms suggesting asthma, such as cough, sputum secretion, and chest tightness with wheezing, for less than a year. Even the best test, histamine challenge, had a sensitivity of only 48%. When more tests were added, sensitivity rose: with peak expiratory flow added, the sensitivity was 65%; with sputum eosinophil cationic protein (ECP) added, to 74%; and with serum ECP added, to 78%. Thus, a combination of tests measuring lung function and activation of eosinophils yielded fair, if not good, results. It appears that sensitivity could be increased further through the development of improved sputum tests.