Prevalence of emm types and antimicrobial susceptibility of Streptococcus dysgalactiae subsp. equisimilis in Austria.
OBJECTIVE
An increase of severe infections caused by Streptococcus dysgalactiae subsp. equisimilis (SDSE) similar to infections caused by Streptococcus pyogenes has been reported over the last years. Little is known about infections with SDSE in Austria. Therefore, we investigated a collection of 113 SDSE invasive and non-invasive isolates from different infection sites and type of infections as well as patients' characteristics.


METHODS
The isolates were phenotypically identified and emm typed using the enlarged emm database from the Centers for Disease Control and Prevention. Additionally, 13 antimicrobial agents were tested using EUCAST guidelines and virulence genes were investigated.


RESULTS
Severe SDSE infections were most common in elderly men with underlying diseases especially diabetes mellitus. With VitekMS identification of SDSE isolates was successful to the species level only. Emm typing revealed 24 different emm types, one new type and one new subtype. StG485, stG6, stC74a, stG643, and stG480 were the predominant types in this study, stC74a and stG652 in invasive infections and stG643, stC74a and stG485 in non-invasive infections. Resistance was observed to tetracycline (62%), macrolides (13%) with one M phenotype, and clindamycin (12%) presenting 6 constitutive MLS(B) phenotypes and 8 inducible MLS(B) phenotypes. Levofloxacin resistance was detected only in one isolate. All isolates tested for virulence genes were positive for scpA, ska, saga and slo. Superantigenic genes were negative except speG(dys) (positive 17/34; 50%).


CONCLUSIONS
This paper presents the first report of SDSE infections in Austria. Severe SDSE infections were found mainly in elderly men with underlying diseases. SDSE isolates demonstrated substantial emm type diversity without association with infections site or invasiveness. Analysis of virulence genes showed no significant difference between invasive and non-invasive infections.
Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Austria.
Eva
E
Leitner
Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Medical University of Graz, Austria. Electronic address: ines.schwetz@medunigraz.at.
Ines
I
Zollner-Schwetz
Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Austria.
Gernot
G
Zarfel
Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Austria.
Lilian
L
Masoud-Landgraf
Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Austria.
Michael
M
Gehrer
Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Austria.
Ute
U
Wagner-Eibel
Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Austria.
Andrea J
AJ
Grisold
Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Austria.
Gebhard
G
Feierl
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000942:Antigens, Bacterial / Q000032:analysis*; D001317:Austria / Q000453:epidemiology; D001425:Bacterial Outer Membrane Proteins / Q000032:analysis*; D002352:Carrier Proteins / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D065288:Serogroup; D013290:Streptococcal Infections / Q000453:epidemiology* / Q000382:microbiology*; D013291:Streptococcus / Q000145:classification* / Q000302:isolation & purification; D055815:Young Adult
D000900:Anti-Bacterial Agents; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; C014689:streptococcal M protein
Antimicrobial susceptibility; Austria; Emm types; Streptococcus dysgalactiae subsp. equisimilis; Virulence genes; Vitek2; VitekMS