High prevalence of group B streptococcus ST17 hypervirulent clone among non-pregnant patients from a Hungarian venereology clinic

Abstract

BackgroundAlthough Streptococcus agalactiae is the leading causative agent of neonatal sepsis and meningitis, recently it is increasingly isolated from non-pregnant adults. The relation between its presence in the genitourinary tract and manifested clinical symptoms of STD patients remains an open question. In this study, a complex epidemiological investigation of GBS isolates from a venerology clinic was performed.MethodsNinety-six GBS isolates were serotyped and their genetic relatedness determined by PFGE. MLST was also performed for a subset of 20 isolates. The antibiotic susceptibility was tested with agar dilution. Surface proteins and the ST-17 hypervirulent clone was detected by PCR.ResultsThe serotype prevalence was the following: V (29.2%), III (27.1%), Ia (22.9%), IV (10.4%), II (5.2%) and Ib (4.2%). A strong association was demonstrated between surface protein genes and serotypes. All isolates were fully susceptible to penicillin, but erythromycin and clindamycin resistance was high (41.7 and 35.4%, respectively), and 8 phenotypically macrolide sensitive isolates carried the ermB gene.21.9% of all strains belonged to the hypervirulent ST17 clone, most being of serotype III and all were rib +. We found a few serotype IV isolates belonging to several STs and one serotype V/ST110 strain, containing a 44-bp deletion in the atr allele.ConclusionsThe presence of silent ermB genes is of worry, as their expression upon macrolide exposure could lead to unforeseen therapeutic failure, while clindamycin is used for intrapartum antibiotic prophylaxis, in case of penicillin allergy. The other alarming result is the high prevalence of ST17 among these strains from STD patients, who could be sources of further infections.This is the first report from Hungary providing both serotyping and genotyping data of GBS isolates. These results could be helpful for vaccine production as the major vaccine candidates are capsular antigens or surface proteins.

Trends in molecular characteristics and antimicrobial resistance of group B streptococci: a multicenter study in Serbia, 2015–2020

“…In the current study, CPS type V was shown to be the most homogenous type. The obtained finding is probably the result of its clonal propagation which is in accordance with previously published reports [35][36][37] . Interestingly, based on the PFGE banding patterns, genotype III/ST17 was less homogenous.…”

“…Interestingly, based on the PFGE banding patterns, genotype III/ST17 was less homogenous. The obtained finding led to the hypothesis that PFGE may distinguish different ST17 lineages 37,38 . Expectedly, the PFGE analysis showed that Table 3.…”

Molecular characterization of high-risk infection vaginal bacteria isolated from pregnant women in CHU-MEL of Cotonou (Benin)

“…High prevalence (61.54%) of these strains was isolated in rectal and vaginal samples from pregnant women approaching childbirth. This result is higher than those reported by Kardos et al (2019) on strains isolated from non-pregnant women. The high prevalence of this strain could be linked to the dissemination of the same clone in southern Benin and a characterization based on the MLST method of the strains could help to better understand this high rate in the population of pregnant women.…”

Molecular Identification of Invasive Non-typeable Group B Streptococcus Isolates From Denmark (2015 to 2017)

“…The hvgA gene connected to the highly virulent ST17/CC17 clone that enables persistent colonization by GBS and contributes to meningitis in neonates (Alhhazmi et al, 2016;Burcham et al, 2019;Kardos et al, 2019) was not found in our strains, except the serotype III reference strain, which belongs to the highly virulent ST17 clone (Supplementary Table 1). Both the scpB and lmb genes were generally detected together in the majority of the isolates in this study (Table 1).…”