Anaerobic pneumonia

Anaerobic bacteria are the more common pathogens in lower respiratory tract infections. The lung infections usually caused by aspiration pneumonia are followed by purulent process, forming lung abscesses or empyema. Clinically, 62% to 100% of aspiration pneumonia is caused by anaerobic bacteria. Anaerobic bacteria in empyema account for 25% to 40%, and some as high as 76%. Due to the problem of specimen collection, the exact proportion of anaerobic bacteria in bacterial pneumonia is not very clear. Some studies have shown that anaerobic bacteria account for 21% to 33% of community pneumonia, second only to Streptococcus pneumoniae, ranking second; there have been reports of up to 35% in hospital pneumonia, but some people think that this data may be significantly overestimated.