Severe community-acquired pneumonia

Community-acquired pneumonia (CAP) is likely to be severe in the very elderly, and clinically significant in these with hepatic/renal insufficiency, cardiopulmonary disease, or, impaired host defenses. Pathogens in mild, moderately severe, and severe CAP are the same. These pathogens determine prognosis, complications, and duration of therapy. Empiric antimocrobial therapy should be based on likely pathogens, not severity of illness which affects the potency but not spectrum of antibiotic selected.