Study of T serotypes and Emm genotypes of Streptococcus pyogenes in children with pharyngitis and tonsillitis.

Streptococcus pyogenes, or group A Streptococcus (GAS), causes superficial infections of the upper respiratory tract that manifest as diseases such as pharyngitis and tonsillitis. T serotypes, emm genotypes, and the antimicrobial susceptibility of GAS isolated from the pharynges of patients with pharyngitis and tonsillitis were studied. The two most common T serotypes were T12 (10/25: 40%) and T1 (7/25: 28%), and the two most common emm genotypes were emm12 (12/27: 44%) and emm1 (7/27: 26%). Good correlation was observed between these T serotypes and emm genotypes.