Drug-resistant pathogens in community- and hospital-acquired pneumonia.

Antimicrobial resistance has been a problem since the early days of the antibiotic era, but in recent years, this resistance has increased in the hospital and is being recognized more in the community setting. Respiratory pathogens such as S. pneumoniae and H. influenzae, for example, have developed resistance to traditional antimicrobial therapy, often over a very short period of time. This increase in resistance patterns requires physicians to closely monitor antimicrobial resistance in their community and to appreciate that some antimicrobial resistance mechanisms may result in resistance for a complete class of antibiotics or different classes of antibiotics with similar mechanisms of action.