Six-Month Multicenter Study on Invasive Infections Due to Streptococcus pyogenes and Streptococcus dysgalactiae subsp. equisimilis in Argentina

Streptococcus pyogenes (group A Streptococcus, GAS) is a human pathogen that causes diseases of various intensity, from mild strep throat to life threatening invasive infections and postinfectional sequelae. S. pyogenes encodes multiple, often phage encoded, virulence factors and their presence is related to severity of the disease. Acquisition of mobile genetic elements, carrying virulence factors, as phages or ICEs (integrative and cojugative elements) has been shown previously to promote selection of virulent clones. We designed the system of eight low volume multi- and one singleplex PCR reactions to detect genes encoding twenty virulence factors (spd3, sdc, sdaB, sdaD, speB, spyCEP, scpA, mac, sic, speL, K, M, C, I, A, H, G, J, smeZ and ssa) and twenty one phage and ICE integration sites described so far for S. pyogenes. Classification of strains based on the phage and virulence factors absence or presence, correlates with PFGE MLST and emm typing results. We developed a novel, fast and cost effective system that can be used to detect GAS virulence factors. Moreover, this system may become an alternative and effective system to differentiate between GAS strains.

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Prevalence and molecular diversity of invasive Streptococcus dysgalactiae and Streptococcus pyogenes in a German tertiary care medical centre

European Journal of Clinical Microbiology & Infectious Diseases ◽

10.1007/s10096-018-3254-2 ◽

2018 ◽

Vol 37 (7) ◽

pp. 1325-1332

Author(s):

S. Rößler ◽

R. Berner ◽

E. Jacobs ◽

N. Toepfner

Keyword(s):

Streptococcus Pyogenes ◽

Molecular Diversity ◽

Tertiary Care ◽

Medical Centre ◽

Streptococcus Dysgalactiae

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Distribution of emm type and antibiotic susceptibility of group A streptococci causing invasive and noninvasive disease

Journal of Medical Microbiology ◽

10.1099/jmm.0.2008/002642-0 ◽

2008 ◽

Vol 57 (11) ◽

pp. 1383-1388 ◽

Cited By ~ 43

Author(s):

Takeaki Wajima ◽

Somay Y. Murayama ◽

Katsuhiko Sunaoshi ◽

Eiichi Nakayama ◽

Keisuke Sunakawa ◽

...

Keyword(s):

Streptococcus Pyogenes ◽

Macrolide Antibiotic ◽

Group A Streptococcus ◽

Acute Otitis Media ◽

Toxic Shock ◽

Medical Institutions ◽

Invasive Infections ◽

Group A ◽

Resistant Strains ◽

Emm Type

To determine the prevalence of macrolide antibiotic and levofloxacin resistance in infections with Streptococcus pyogenes (group A streptococcus or GAS), strains were collected from 45 medical institutions in various parts of Japan between October 2003 and September 2006. Four hundred and eighty-two strains from patients with GAS infections were characterized genetically. Strains were classified into four groups according to the type of infection: invasive infections (n=74) including sepsis, cellulitis and toxic-shock-like syndrome; acute otitis media (AOM; n=23); abscess (n=53); and pharyngotonsillitis (n=332). Among all strains, 32 emm types were identified; emm1 was significantly more common in invasive infections (39.2 %) and AOM (43.5 %) than in abscesses (3.8 %) or pharyngotonsillitis (10.2 %). emm12 and emm4 each accounted for 23.5 % of pharyngotonsillitis cases. Susceptibility of GAS strains to eight β-lactam agents was excellent, with MICs of 0.0005–0.063 μg ml−1. Macrolide-resistant strains accounted for 16.2 % of all strains, while the percentages of strains possessing the resistance genes erm(A), erm(B) and mef(A) were 2.5 %, 6.2 % and 7.5 %, respectively. Although no strains with high resistance to levofloxacin were found, strains with an MIC of 2–4 μg ml−1 (17.4 %) had amino acid substitutions at either Ser-79 or Asp-83 in ParC. These levofloxacin-intermediately resistant strains included 16 emm types, but macrolide-resistant strains were more likely than others to represent certain emm types.

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Necrotizing soft tissue infections caused by Streptococcus pyogenes and Streptococcus dysgalactiae subsp. equisimilis of groups C and G in western Norway

Clinical Microbiology and Infection ◽

10.1111/1469-0691.12276 ◽

2013 ◽

Vol 19 (12) ◽

pp. E545-E550 ◽

Cited By ~ 41

Author(s):

T. Bruun ◽

B.R. Kittang ◽

B.J. de Hoog ◽

S. Aardal ◽

H.K. Flaatten ◽

...

Keyword(s):

Soft Tissue ◽

Streptococcus Pyogenes ◽

Soft Tissue Infections ◽

Streptococcus Dysgalactiae ◽

Western Norway ◽

Necrotizing Soft Tissue Infections

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Streptococcus pyogenes evades adaptive immunity through specific IgG glycan hydrolysis

Journal of Experimental Medicine ◽

10.1084/jem.20190293 ◽

2019 ◽

Vol 216 (7) ◽

pp. 1615-1629 ◽

Cited By ~ 2

Author(s):

Andreas Naegeli ◽

Eleni Bratanis ◽

Christofer Karlsson ◽

Oonagh Shannon ◽

Raja Kalluru ◽

...

Keyword(s):

Streptococcus Pyogenes ◽

Vaccine Development ◽

Group A Streptococcus ◽

Invasive Infection ◽

Invasive Infections ◽

Life Threatening ◽

Group A ◽

Specific Igg

Streptococcus pyogenes (Group A streptococcus; GAS) is a human pathogen causing diseases from uncomplicated tonsillitis to life-threatening invasive infections. GAS secretes EndoS, an endoglycosidase that specifically cleaves the conserved N-glycan on IgG antibodies. In vitro, removal of this glycan impairs IgG effector functions, but its relevance to GAS infection in vivo is unclear. Using targeted mass spectrometry, we characterized the effects of EndoS on host IgG glycosylation during the course of infections in humans. Substantial IgG glycan hydrolysis occurred at the site of infection and systemically in the severe cases. We demonstrated decreased resistance to phagocytic killing of GAS lacking EndoS in vitro and decreased virulence in a mouse model of invasive infection. This is the first described example of specific bacterial IgG glycan hydrolysis during infection and thereby verifies the hypothesis that EndoS modifies antibodies in vivo. This mechanisms of immune evasion could have implications for treatment of severe GAS infections and for future efforts at vaccine development.

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