Rheumatic fever studies, streptococcal

The evidence that treatment of group A streptococcal pharyngitis prevents rheumatic fever comes solely from studies using depot intramuscular penicillin. Penicillin administered by other routes has been assumed to be equally efficacious. The ability of other antibiotics to eradicate group A Streptococcus has led to extrapolation that these agents also will prevent rheumatic fever. 

Antimicrobial treatment should be limited to those who have clinical and epidemiologic features of group A streptococcal pharyngitis with a positive laboratory test. Penicillin is the drug of choice in the treatment of group A streptococcal pharyngitis (Table 107-8). It has the narrowest spectrum of activity, and it is effective, safe, and inexpensive. The only controlled studies that have demonstrated that antimicrobial therapy prevents rheumatic fever were done with procaine penicillin, which was later replaced with benzathine penicillin. " ... 

Pediatric studies of pharyngitis and tonsillitis showed that azithromycin was not as effective as a 10-day course of penicillin V. However, it was felt that part ol the problem could be attributed to the presence of macrolide resistance (17% in one study) [184-187]. At least two large double-blind, multicenter studies using a higher dose of azithromycin for 5 days in children with streptococcal pharyngitis have shown that azithromycin was clinically superior to a 10-day course ol penicillin V [187, 188]. We have no clinical evidence of the efficacy of azithromycin in prevention of rheumatic fever. 

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