We studied the antimicrobial susceptibility of 322 Streptococcus pyogenes throat isolates from French children and their serotype and genomic diversity. A total of 22.4% were erythromycin resistant, and 69.4, 4.2, and 26.4% of these isolates harbored ermB, ermA, and mefA, respectively. Increasing resistance in France is mainly associated with a few emm type 28 clones.Streptococcus pyogenes pharyngitis is one of the most common bacterial upper respiratory tract infections in children. Group A streptococci (GAS) are uniformly susceptible to penicillin. Macrolides are recommended alternatives for penicillinhypersensitive patients. However, resistance to erythromycin has become widespread among GAS (4, 6, 10, 18, 19; L. Mihaila-Amrouche, J. Loubinoux, and A. Bouvet, Abstr. 13th Eur. Congr. Clin. Microbiol. Infect. Dis., abstr. S6, 2003.). Here, we studied the prevalence of macrolide resistance among recent throat isolates of GAS collected from children throughout France. We also determined their mechanisms of resistance and their clonality by means of emm genotyping and pulsed-field gel electrophoresis (PFGE).A total of 322 consecutive S. pyogenes isolates were collected between 2002 and 2003 throughout France. They were isolated from throat cultures of children 2 to 16 years of age (mean, 6 years) with pharyngitis. The isolates were identified as S. pyogenes by colony morphology, Gram staining, beta-hemolysis on blood agar, and the presence of group A antigen as determined by an agglutination test (Oxoid, Basingstoke, United Kingdom).Antimicrobial susceptibility was tested as recommended previously (15). Erythromycin-resistant strains were identified by the disk diffusion method on Mueller-Hinton agar supplemented with 5% defibrinated sheep blood (Bio-Rad, Marnes la Coquette, France) using 15-IU erythromycin disks (Bio-Rad) (15). Bacitracin susceptibility was studied by the disk diffusion method with 10-IU disks (Bio-Rad).The MICs of amoxicillin, penicillin G, erythromycin, azithromycin, clarithromycin, telithromycin, clindamycin, and streptogramin B were determined for all isolates with erythromycin inhibition zone diameters of less than 21 mm (14). Telithromycin interpretative criteria for susceptibility and resistance were Յ0.5 and Ն4 g/ml, respectively (NCCLS approved breakpoints are not available) (7).The mefA, ermB, and ermA genes were detected by PCR amplification as previously described (3).Biotypes were determined as previously described (5). T serotypes were determined on trypsinated bacteria by slide agglutination with anti-T sera obtained from the Institute of Sera and Vaccines, Prague, Czech Republic (9).emm-specific PCR products were obtained with the primers MF2 and MR1 described by Podbielski et al. (17). The 5Ј end of the emm genes was sequenced as described by Beall et al. (2) (see the Centers for Disease Control and Prevention website [http://www.cdc.gov/ncidod/biotech/strep/protocols.htm]). DNA sequences were subjected to homology searches (http://www .cdc.gov/ncidod/biotech/strep/strepblast.htm...
The proportion of infective endocarditis (IE) caused by group D streptococci (GDS; formerly Streptococcus bovis) increased markedly in France, to account for 25% of all cases of IE by 1999. In an attempt to explain this phenomenon, a comparative analysis of GDS and oral streptococci (OS) causing IE was performed. This study was based on data collected from a large cross-sectional population-based survey that was conducted in 1999. In total, 559 cases of definite IE were recorded, of which 142 involved GDS and 79 involved OS. Patients with GDS IE were older (62.7 vs. 56.6 years, p 0.01) and had a history of valve disease less frequently than did patients with OS IE (33.8% vs. 67.1%, p <0.0001). At-risk procedures for IE were performed less frequently in patients with GDS than in patients with OS (14.8% vs. 24.1%, p 0.08), but co-morbidities were more frequent in the GDS group (59.9% vs. 32.9%, p 0.0001). Diabetes, colon diseases and cirrhosis were also more frequent in the GDS group (p 0.006, p <0.0001 and p 0.08, respectively). Rural residents accounted for 31.0% of the GDS group, but for only 15.2% of the OS group (p 0.001). Likewise, the proportion of GDS IE was higher in regions with mixed (urban and rural) populations (Franche-Comté 81.8%, Marne 68.7%, Lorraine 70.3% and Rhône-Alpes 65.3%) than in exclusively urban regions (Paris and Ile de France 58.0%). Further investigations are required to elucidate the link in France between the incidence of GDS IE, rural residency and nutritional factors.
Fifty-three pharyngitis-related and invasive isolates of Streptococcus pyogenes that are resistant to bacitracin were collected. They were also resistant to streptomycin, kanamycin, macrolides, lincosamides, and streptogramin B. These multiresistant isolates were of emm type 28 and clonally related as shown by pulsed-field gel electrophoresis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.