Chlamydia pneumoniae and chronic lung diseases.

Chlamydia pneumoniae infection has been implicated in several chronic lung diseases by serology and direct antigen detection. Acute lower respiratory tract infection caused by C. pneumoniae seems often to precede attacks of asthma in both children and adults. Chlamydia pneumoniae is also involved in some exacerbations of chronic bronchitis and chronic obstructive lung disease but, more importantly, seems to be strongly associated with the latter irrespective of exacerbation status. Moreover, persistently elevated C. pneumoniae antibody titres have been observed in sarcoidosis and lung cancer.