Role of viruses and bacteria in acute wheezy bronchitis in childhood: a study of sputum.

Sputum, nasal swabs, and throat swabs were obtained from 22 children aged between 5 and 15 years during 72 attacks of wheezy bronchitis. A virus, most commonly a rhinovirus, was isolated in 49% of all episodes and in 64% of 22 severe episodes requiring treatment with corticosteroids; the isolation rate was higher early in the illness than later. Virus was recovered more often from sputum than from the nose or throat, suggesting that viral replication occurs freely in the lower respiratory tract: the cytological findings in sputum were compatible with an inflammatory response to viral infection. Pathogenic bacteria appeared to play a minor role compared with viruses, and routine antibiotic treatment was probably of little value in moost cases. The significance of the results is discussed in relation to the pathogenesis of childhood wheezy bronchitis.