Pharyngitis microbiology

Acute pharyngitis presents a diagnostic and therapeutic dilemma. The majority of sore throats are caused by a variety of viruses fewer than 20% are bacterial and hence potentially responsive to antibiotic therapy. However, antibiotics are widely prescribed and this reflects the difficulty in discriminating streptococcal from non-streptococcal infections clinically in the absence of microbiological documentation. Nonetheless, Strep, pyogenes is the most important bacterial pathogen and this responds to oral penicillin. However, up to 10 days treatment is required for its eradication fixm the throat. This requirement causes problems with compliance since symptomatic improvement generally occurs within 2-3 days. 

Varaldo PE, Debbia EA, Nicoletti G, Pavesio D, Ripa S, Schito GC, Tempera G. Nationwide survey in Italy of treatment of Streptococcus pyogenes pharyngitis in children influence of macrolide resistance on clinical and microbiological outcomes. Artemis-Italy Study Group. Clin Infect Dis 1999 29(4) 869-73. 

A 7-year-old child presents with pharyngitis and fever of 2 days duration, and microbiology reveals small, translucent beta-hemolytic colonies sensitive in vitro to bacitracin. Past history includes a severe allergic reaction to amoxicillin when used for an ear infection. You need to treat this infection, but you prefer not to use a drug that needs parenteral administration. Which one of the following agents is most likely to be appropriate in terms of both effectiveness and safety ... 

Still, J. G. (1994). Treatment of streptococcal pharyngitis in children with five days of azithromycin suspension. In Program of the 34th Interscience Conference on Antimicrobial Agents and Chemotherapy, Abstr. No. M67. American Society for Microbiology, Washington, DC. 

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