Chlamydia pneumoniae and the lung.

Chlamydia pneumoniae is a frequently occurring respiratory pathogen affecting all age groups. It may cause 5-20% of community-acquired pneumonias in adults and children. The organism has also been implicated as an infectious trigger for asthma. Furthermore, new studies suggest that it may play a role in the pathogenesis of several chronic diseases including atherosclerosis. However, despite the growing significance of C. pneumoniae as a pathogen, progress is hampered by the lack of standardized diagnostic methods including serology and polymerase chain reaction. This makes it practically impossible for the practitioner to make a specific microbiological diagnosis. The lack of standardized methods has also had an adverse effect on treatment trials. The dependence on serology for diagnosis in treatment studies has generated some questionable results. Unless cultures are performed, microbiological efficacy cannot be assessed and it may never be possible to survey for or document the emergence of resistance.