Molecular characterization of invasive Streptococcus dysgalactiae subsp. equisimilis. Multicenter study: Argentina 2011-2012.
Streptococcus dysgalactiae subsp. equisimilis (SDSE) has virulence factors similar to those of Streptococcus pyogenes. Therefore, it causes pharyngitis and severe infections indistinguishable from those caused by the classic pathogen. The objectives of this study were: to know the prevalence of SDSE invasive infections in Argentina, to study the genetic diversity, to determine the presence of virulence genes, to study antibiotic susceptibility and to detect antibiotic resistance genes. Conventional methods of identification were used. Antibiotic susceptibility was determined by the disk diffusion and the agar dilution methods and the E-test. Twenty eight centers from 16 Argentinean cities participated in the study. Twenty three isolates (16 group G and 7 group C) were obtained between July 1 2011 and June 30 2012. Two adult patients died (8.7%). Most of the isolates were recovered from blood (60.9%). All isolates carried speJ and ssa genes. stG62647, stG653 and stG840 were the most frequent emm types. Nineteen different PFGE patterns were detected. All isolates were susceptible to penicillin and levofloxacin, 6 (26.1%) showed resistance or reduced susceptibility to erythromycin [1 mef(A), 3 erm(TR), 1 mef(A)+erm(TR) and 1 erm(TR)+erm(B)] and 7 (30.4%) were resistant or exhibited reduced susceptibility to tetracycline [2 tet(M), 5 tet(M)+tet(O)]. The prevalence in Argentina was of at least 23 invasive infections by SDSE. A wide genetic diversity was observed. All isolates carried speJ and ssa genes. Similarly to other studies, macrolide resistance (26.1%) was mainly associated to the MLSBphenotype.
Servicio de Microbiología, Hospital de Pediatría Prof. Dr. Juan P Garrahan, Buenos Aires, Argentina; Nueva Clínica Chacabuco, Tandil, Buenos Aires, Argentina; Servicio de Neumotisiología, Tandil, Buenos Aires, Argentina. Electronic address: fernandotraverso@yahoo.com.ar.
Fernando
F
Traverso
Servicio de Microbiología, Hospital de Pediatría Prof. Dr. Juan P Garrahan, Buenos Aires, Argentina.
Alejandra
A
Blanco
Centro Nacional de Microbiología ISCIII, Majadahonda, Madrid, Spain.
Pilar
P
Villalón
Servicio de Microbiología, Hospital de Pediatría Prof. Dr. Juan P Garrahan, Buenos Aires, Argentina.
Noelia
N
Beratz
Centro Nacional de Microbiología ISCIII, Majadahonda, Madrid, Spain.
Juan Antonio
JA
Sáez Nieto
Servicio de Microbiología, Hospital de Pediatría Prof. Dr. Juan P Garrahan, Buenos Aires, Argentina.
Horacio
H
Lopardo
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001118:Argentina / Q000453:epidemiology; D001170:Arthritis, Infectious / Q000453:epidemiology / Q000382:microbiology; D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology*; D001826:Body Fluids / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D005798:Genes, Bacterial; D014644:Genetic Variation; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D018461:Soft Tissue Infections / Q000453:epidemiology / Q000382:microbiology; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D013291:Streptococcus / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D013297:Streptococcus pyogenes / Q000235:genetics / Q000302:isolation & purification; D014774:Virulence; D055815:Young Adult
D004269:DNA, Bacterial
Estreptococos del grupo C; Estreptococos del grupo G; Group C streptococci; Group G streptococci; Infección invasiva; Invasive infection; Streptococcus dysgalactiae subsp. equisimilis