Sore throat: to culture or not to culture.

The traditional use of the throat culture to guide treatment of potential streptococcal pharyngitis recently has been questioned because of the following facts: antibiotic therapy within the first 48 hours of illness reduces the severity and symptoms of streptococcal pharyngitis; more rapid treatment of streptococcal pharyngitis may be more effective in prevention of rheumatic fever; clinical and Gram stain criteria can identify individuals with a high probability of a positive throat culture; new latex agglutination tests can identify within minutes individuals with a high probability of a positive throat culture; the throat culture may be falsely negative in individuals with partially treated pharyngitis, an inadequately swabbed or plated specimen, or an improperly read culture plate; and incomplete patient followup increases the true societal cost of traditional therapy based on throat culture results. These issues suggest that a sufficiently accurate screening test for guiding antibiotic therapy at the initial visit may be more clinically beneficial and cost effective than recalling all positive throat culture patients for antibiotic therapy. Nonetheless, a throat culture remains important when a screening test of a patient with suspected streptococcal pharyngitis is negative. Indications for culturing pharyngitis for other potential pathogens also are discussed.