%0 Journal Article
%T Group A streptococcal genotypes from throat and skin isolates in the United Arab Emirates
%A Mubarak S Alfaresi
%J BMC Research Notes
%D 2010
%I BioMed Central
%R 10.1186/1756-0500-3-94
%X A total of 38 GAS isolates were analyzed, including 35 isolates from throat and 3 from skin. Among the 38 isolates, a total of 25 different emm/st types were detected: 20 isolates (53%) belonged to 16 validated standard reference emm types and 18 isolates (47%) belonged to 9 recognized sequence types.This is the first emm typing study in the United Arab Emirates to demonstrate the heterogeneity of the GAS population.The bacterium Streptococcus pyogenes causes a variety of human diseases that range from relatively mild skin infections to severe invasive diseases, such as acute rheumatic fever, glomerulonephritis, puerperal sepsis, necrotizing fasciitis, meningitis, and streptococcal toxic shock syndrome [1-3].Accurate identification and typing of group A hemolytic streptococci (GAS) is essential for epidemiological and pathogenetic studies of streptococcal diseases. Rebecca Lancefield developed a serotyping system based on antigenic variation of the cell surface M protein that has been in use since 1928. Although additional serotyping systems, i.e. T and OF typing, were developed as valuable and practical substitutes, the M typing system has been considered the gold standard method. However, a limited supply of antisera and the high nontypeability rate among isolates, in particular among isolates from the tropics, present a challenge to using the M typing system. In recent years, several molecular typing systems have been developed as alternatives to M typing [4-7].Numerous typing schemes have been used to characterize and measure genetic diversity among S. pyogenes isolates. Perhaps the most common tool used today is emm typing. The emm typing system [4,6,7], which is based on sequence analysis of PCR products of the N-terminal hypervariable region of the M protein gene, concurs with M serotyping almost 1:1. In addition to its simplicity, emm typing has allowed the detection of several previously unknown GAS types from different geographic regions [8-11]. Knowledge
%U http://www.biomedcentral.com/1756-0500/3/94