scholarly journals Epidemiological and molecular characteristics of clinical isolates of Streptococcus pyogenes collected between 2005 and 2008 from Chinese children

2012 ◽  
Vol 61 (7) ◽  
pp. 975-983 ◽  
Author(s):  
Yunmei Liang ◽  
Xiaorong Liu ◽  
Hesheng Chang ◽  
Lili Ji ◽  
Guoying Huang ◽  
...  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Siiri Kõljalg ◽  
Risto Vaikjärv ◽  
Imbi Smidt ◽  
Tiiu Rööp ◽  
Anirikh Chakrabarti ◽  
...  

AbstractPolyols are effective against caries-causing streptococci but the effect on oropharynx-derived pyogenic streptococci is not well characterised. We aimed to study the effect of erythritol (ERY) and xylitol (XYL) against Streptococcus pyogenes isolated from peritonsillar abscesses (PTA). We used 31 clinical isolates and 5 throat culture collection strains. Inhibition of bacterial growth by polyols at 2.5%, 5% and 10% concentrations was studied and the results were scored. Amylase levels in PTA pus were compared to polyol effectivity scores (PES). Growth curves of four S. pyogenes isolates were analysed. Our study showed that XYL was more effective than ERY inhibiting 71–97% and 48–84% of isolates, respectively, depending of concentrations. 48% of clinical and all throat strains were inhibited by polyols in all concentrations (PES 3). PES was negative or zero in 26% of the isolates in the presence of ERY and in 19% of XYL. ERY enhanced the growth of S. pyogenes isolated from pus with high amylase levels. Polyols in all concentrations inhibited the growth in exponential phase. In conclusion, ERY and XYL are potent growth inhibitors of S. pyogenes isolated from PTA. Therefore, ERY and XYL may have potential in preventing PTA in the patients with frequent tonsillitis episodes.


2012 ◽  
Vol 56 (10) ◽  
pp. 5424-5425 ◽  
Author(s):  
René Bergmann ◽  
Vivek Sagar ◽  
D. Patric Nitsche-Schmitz ◽  
Gursharan S. Chhatwal

PLoS ONE ◽  
2013 ◽  
Vol 8 (5) ◽  
pp. e64359 ◽  
Author(s):  
Hisakazu Yano ◽  
Mina Uemura ◽  
Shiro Endo ◽  
Hajime Kanamori ◽  
Shinya Inomata ◽  
...  

2021 ◽  
Vol 12 ◽  
Author(s):  
Dingle Yu ◽  
Yunmei Liang ◽  
Qinghua Lu ◽  
Qing Meng ◽  
Wenjian Wang ◽  
...  

Streptococcus pyogenes is a bacterial pathogen that causes a wide spectrum of clinical diseases exclusively in humans. The distribution of emm type, antibiotic resistance and virulence gene expression for S. pyogenes varies temporally and geographically, resulting in distinct disease spectra. In this study, we analyzed antibiotic resistance and resistance gene expression patterns among S. pyogenes isolates from pediatric patients in China and investigated the relationship between virulence gene expression, emm type, and disease categories. Forty-two representative emm1.0 and emm12.0 strains (n = 20 and n = 22, respectively) isolated from patients with scarlet fever or obstructive sleep apnea-hypopnea syndrome were subjected to whole-genome sequencing and phylogenetic analysis. These strains were further analyzed for susceptibility to vancomycin. We found a high rate and degree of resistance to macrolides and tetracycline in these strains, which mainly expressed ermB and tetM. The disease category correlated with emm type but not superantigens. The distribution of vanuG and virulence genes were associated with emm type. Previously reported important prophages, such as φHKU16.vir, φHKU488.vir, Φ5005.1, Φ5005.2, and Φ5005.3 encoding streptococcal toxin, and integrative conjugative elements (ICEs) such as ICE-emm12 and ICE-HKU397 encoding macrolide and tetracycline resistance were found present amongst emm1 or emm12 clones from Shenzhen, China.


2019 ◽  
Author(s):  
Gustavo Enck Sambrano ◽  
Gustavo P Riboldi ◽  
Keli C Reiter ◽  
Thiago Galvão da Silva Paim ◽  
Neidmar Correa Tolfo ◽  
...  

Background: Streptococcus pyogenes, a Group A streptococci (GAS), is an important human pathogen that causes a wide range of infections. Methods: Twenty five clinical isolates of S. pyogenes were submitted to an emm typing and to a Real-time PCR analysis for 23 important virulence factors. Results: Fourteen emm types were found and the emm1 type was the most prevalent. The majority of the isolates were classified as emm pattern E, followed by A-C3. No pattern D was found. Among the virulence factors, the most prevalent were SpeG, Slo, C5a-peptidase and SPNA. Phage encoded virulence genes were also found among the strains, such as mf-2, SpeJ and SpeL. Discussion: The emm1 type was the most prevalent while the 13 others M types were distributed along the strains. No tissue tropism was found on the isolates. The virulence factors analysis demonstrated that chromosomally and phage-encoded genes were found, which confers a potential for high virulent micro-organisms.


2019 ◽  
Author(s):  
Gustavo Enck Sambrano ◽  
Gustavo P Riboldi ◽  
Keli C Reiter ◽  
Thiago Galvão da Silva Paim ◽  
Neidmar Correa Tolfo ◽  
...  

Background: Streptococcus pyogenes, a Group A streptococci (GAS), is an important human pathogen that causes a wide range of infections. Methods: Twenty five clinical isolates of S. pyogenes were submitted to an emm typing and to a Real-time PCR analysis for 23 important virulence factors. Results: Fourteen emm types were found and the emm1 type was the most prevalent. The majority of the isolates were classified as emm pattern E, followed by A-C3. No pattern D was found. Among the virulence factors, the most prevalent were SpeG, Slo, C5a-peptidase and SPNA. Phage encoded virulence genes were also found among the strains, such as mf-2, SpeJ and SpeL. Discussion: The emm1 type was the most prevalent while the 13 others M types were distributed along the strains. No tissue tropism was found on the isolates. The virulence factors analysis demonstrated that chromosomally and phage-encoded genes were found, which confers a potential for high virulent micro-organisms.


2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S359-S360 ◽  
Author(s):  
Fiorella Krapp ◽  
Catherine Amaro ◽  
Karen Ocampo ◽  
Lizeth Astocondor ◽  
Noemi Hinostroza ◽  
...  

Abstract Background In contrast with other countries in Latin America, Peru had been notoriously spared by the global dissemination of carbapenem-resistant Klebsiella pneumoniae (CR-Kp), until recently. Even though, isolated cases of KPC-producing K. pneumoniae had been reported since 2013, it was not until 2016 that the first outbreak of NDM- producing K. pneumoniae was described in Peru. By 2017, rapid emergence of CR-Kp took place in Hospital Cayetano Heredia (HCH), a tertiary care hospital in Lima. Here, we provide a description of clinical, microbiological and molecular characteristics of CR-Kp isolates recovered at HCH. Methods Retrospective review of all CR-Kp clinical isolates recovered at HCH until December 2017. Antibiotic susceptibility data were obtained during routine care (Vitek or disc diffusion) and was assessed using CLSI breakpoints. DNA extraction was performed by heat shock, and PCR was performed to assess carriage of blaNDM gene. String test was performed to detect hypermucoviscosity. Results The first case of CR-Kp in HCH dated from July 2015. Since then, a total of 69 CR-Kp clinical isolates, from 60 patients have been recovered until December 2017. A significant increase in the number of cases was observed during 2017 (Figure 1). The average age of patients was 55. Urinary, and respiratory sources of infection or colonization were the most common ones (35% and 30%, respectively), followed by blood stream (17%) and intraabdominal (10%) infections. Isolate recovery and DNA extraction was achieved in 40 cases. Of these, 15 (38%) had a positive PCR for blaNDM carbapenemase gene (Figure 2). Antibiotic susceptibility testing revealed that amikacin was the most effective antimicrobial with the rest of antimicrobials having extremely high rates of resistance (Figure 3). String test was positive in two of these isolates, suggesting that hypervirulent CR-KP might be emerging in this region. Conclusion An epidemic of CR-Kp has established in our hospital, representing the first one reported in Peru. The different mechanisms of carbapenem resistance found suggest a polyclonal expansion. Amikacin remains the only active antimicrobial within the routinely tested antibiotics, highlighting the need to add other antimicrobials to the routine panel. Disclosures All authors: No reported disclosures.


2015 ◽  
Vol 83 (4) ◽  
pp. 518-526 ◽  
Author(s):  
Jing Cheng ◽  
Ruizhu Lin ◽  
Wen Zhang ◽  
Guochang Liu ◽  
Huiying Sheng ◽  
...  

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