XXXX phenotypes: consistency of classification using induced sputum.

@entity1712 @entity565 @entity1 @entity228
BACKGROUND AND OBJECTIVE: @entity565 can be classified as eosinophilic or non-eosinophilic based on the cell profile of induced sputum. This classification can help determine whether @entity228 treatment is indicated. We assessed the stability of these phenotypes over time and with different treatment regimens. METHODS: Clinically stable, non-smoking, asthmatic adults were enrolled in one of two studies. In study one, induced sputum cell counts from 28 subjects were analysed after 4 weeks without @entity228 treatment and after 6 week treatments with placebo, regular inhaled beta-agonist, inhaled @entity228 , and combined beta-agonist and @entity228 . In study two, sputum from 26 subjects with @entity1712 was analysed after 12 weeks of placebo and after four 2-week @entity228 washouts. Sputum with <2% eosinophils was classified as non-eosinophilic. RESULTS: Sputum classification changed frequently in both studies. In study one, only one of eight @entity1 with non-eosinophilic sputum after placebo treatment remained non-eosinophilic throughout. In study two, all of @entity1 had at least one eosinophilic sputum sample, despite the fact that all had been non-eosinophilic at recruitment. @entity565 was uncommon in both studies and was also inconsistent. CONCLUSIONS: The phenotypic classification of asthma changes frequently. A diagnosis of @entity1712 should not be based on a single sputum sample.
