RESUMO
BACKGROUND: We set out to examine which treatment option available in the United States was most cost-effective in treating children with endemic group A streptococcal pharyngitis to prevent rheumatic heart disease. METHODS: Cost-effectiveness was calculated from the societal perspective and expressed in cases of rheumatic heart disease prevented annually in the U.S. pediatric population aged 5 to 17 based on U.S. Census data. We used a decision-analysis model to assess the cost-effectiveness of five treatment options for patients with pharyngitis: (1) "treat all," (2) "treat none," (3) "rapid test," where only patients with a positive rapid antigen test are treated, (4) "culture," where only patients with a positive throat culture are treated, and (5) "rapid test with culture" or (RTCX), where confirmatory cultures are used on patients with negative rapid tests. Cost data were gathered from existing empirical data or estimated. We performed sensitivity analyses of the antigen test sensitivity and antibiotic effectiveness and examined whether changes in these variables would alter our outcome. RESULTS: The "rapid test" was the most cost-effective option. Using "rapid tests" prevented 85 cases of rheumatic heart disease annually and cost society $727,000 per case prevented. Performing throat cultures instead of "rapid tests" would pick up an additional 11 cases of rheumatic heart disease but would cost $13.7 million for each of these additional cases prevented. The current standard of using throat cultures as a confirmatory test on patients with a negative "rapid" test would detect an additional 21 cases of rheumatic heart disease but cost society an additional $8 million per case prevented. CONCLUSIONS: To reduce the incidence of rheumatic heart disease cost-effectively, the management of pediatric pharyngitis may best be accomplished by using antigen testing. The added costs associated with the remaining treatment options may not be justified, especially, as the sensitivity of the antigen tests continues to improve and closely approaches the sensitivity of the practice standard, throat culture.