Community-acquired pneumonia: the evolving challenge.

Community-acquired pneumonia (CAP) is a common disorder that has been the focus of a major international research effort to define its epidemiology, etiology and management. The microbial etiology of CAP is complex and severity assessment is important in identifying at-risk populations as well as defining therapeutic strategies. Laboratory investigations rarely influence initial therapy, which remains empirical. Guidelines have been developed in many countries in response to the need to optimize management and outcomes. However, many of these guidelines have been based on expert opinion rather than robust evidence. New evidence-based guidelines have been developed that take into account disease severity, the local distribution of pathogens and their likely susceptibility to antimicrobials, and that include newer treatment options. Macrolide and fluoroquinolone antimicrobials feature heavily in these new treatment recommendations. Promising new therapies continue to emerge that may offer advantages over fluoroquinolones and macrolides, in particular with regard to the problem of resistance. Of these, the ketolides are of special interest. Telithromycin, the first ketolide antibacterial, has been evaluated in the treatment of > 700 patients with CAP. A once-daily oral dose of telithromycin 800 mg for 7-10 days produces clinical and bacteriological success rates > 90% and equivalent to standard comparator agents, whilst maintaining efficacy against resistant pathogens.