Streptococcal toxic shock syndrome caused by the dissemination of an invasive emm3/ST15 strain of Streptococcus pyogenes

Tsuyoshi Sekizuka, Emina Nai, Tomohiro Yoshida, Shota Endo, Emi Hamajima, Satoka Akiyama, Yoji Ikuta, Natsuko Obana, Takahiro Kawaguchi, Kenta Hayashi, Masahiro Noda, Tomoko Sumita, Masayuki Kokaji, Tatsuo Katori, Masanori Hashino, Kunihiro Oba, Makoto Kuroda

Streptococcus pyogenes (group A Streptococcus [GAS]) is a major human pathogen that causes a wide spectrum of clinical manifestations. Although invasive GAS (iGAS) infections are relatively uncommon, emm3/ST15 GAS is a highly virulent, invasive, and pathogenic strain. Global molecular epidemiology analysis has suggested that the frequency of emm3 GAS has been recently increasing. A 14-year-old patient was diagnosed with streptococcal toxic shock syndrome and severe pneumonia, impaired renal function, and rhabdomyolysis. GAS was isolated from a culture of endotracheal aspirates and designated as KS030. Comparative genome analysis suggested that KS030 is classified as emm3 (emm-type) and ST15 (multilocus sequencing typing [MLST]), which is similar to iGAS isolates identified in the UK (2013) and Switzerland (2015). We conclude that the global dissemination of emm3/ST15 GAS strain has the potential to cause invasive disease.