Community-acquired pneumonia in adults: initial antibiotic therapy

Community-acquired pneumonia is a common infection encountered in clinical practice and is the leading cause of death due to infectious disease in the United States. To choose initial antimicrobial therapy appropriately, physicians must keep informed of recent developments in the epidemiology and clinical manifestations of atypical pathogens, antibiotic resistance and new antibiotics. Differentiating between "typical" and "atypical" pneumonia based on the initial clinical presentation is difficult. Primary treatment for community-acquired pneumonia in young adults without comorbidities is erythromycin. Older adults or those with comorbidities should be treated with erythromycin plus trimethoprim-sulfamethoxazole, a second- or third-generation cephalosporin, or a new macrolide. Empiric therapy for moderately or severely III hospitalized patients usually begins with erythromycin plus a second- or third-generation cephalosporin. Physicians should use initial antibiotic therapy for coverage of both typical and atypical pathogens.