Anaerobic disease of the lung.

Anaerobic pleuropulmonary infections present in various ways. Aspiration pneumonitis occurs first and may be quite difficult to distinguish from the acute bacterial pneumonia caused by Streptococcus pneumoniae and other organisms. Although aspiration pneumonitis may be self-limiting, sequelae such as lung abscess, necrotizing pneumonia, and empyema can develop. Empiric antimicrobial therapy is now acceptable. The initial choice of antimicrobial agents is based on which pathogens are likely to be involved.