Antimicrobial resistance and molecular characterization of Streptococcus agalactiae from pregnant women in southern China

Abstract

Introduction: This study aimed to characterize antimicrobial resistance (AMR), molecular determinants of AMR and virulence, as well as clonal relationship of Streptococcus agalactiae isolates from women at 35-37 weeks of gestation in the Chaoshan metropolitan area of southern China.
 Methodology: Bacterial strains isolated from vaginal swabs were identified and antimicrobial susceptibility tests were performed by using a Vitek 2 Compact system (BioMérieux, France). Resistance and virulence genes were detected by polymerase chain reaction (PCR) and the clonal relationship was analysed by multiple locus variable number tandem repeat analysis (MLVA). Statistical analysis was carried out by using SPSS software, version 19.0.
 Results: All GBS were susceptible to benzylpenicillin, ampicillin, quinupristin/dalfopristin, tigecycline, linezolid and vancomycin, but a considerable proportion was resistant to clindamycin (29.67%), erythromycin (46.15%)， azithromycin (63.74%), tetracycline (84.62%) and quinolones (25.27%). The carrier rates of ermB (69.04%) and mefA/E (64.28%) were detected in these GBS strains resistant to erythromycin. In terms of MLVA detection, 91 GBS strains were categorized into 43 genotypes and 6 clusters. All GBS harboured hylB and cylE genes, most of which carried a combination of PI-1 and PI-2a genes as a common virulence gene profile.
 Conclusions: The high level of resistance conferred by some corresponding resistance genes to macrolides, lincosamides and quinolones of GBS isolates from pregnant women in southern China, has reinforced the necessity for monitoring GBS strain resistance to the above agents. Comparative genetic studies of GBS isolates, especially efforts to understand the relationship between pilus islands and genotype, were essential for conducting infection control and epidemiological comparisons between countries.

Prevalence and antimicrobial resistance in Streptococcus agalactiae isolated from raw milk in Pasuruan and Lumajang districts, East Java, Indonesia

“…Prudent use of antimicrobial therapies and monitoring of antimicrobial susceptibility of bacterial flora in animals are two examples of recommendations to achieve this goal (OIE 2016). Antimicrobial therapy should be guided by the antimicrobial susceptibility test and the necessity for the continuous monitoring of antimicrobial susceptibility profiles should also be emphasized, as well in general (Guo et al 2019). The resistance is due to one of four general mechanisms: (1) inactivation of antibiotic by β-lactamase, (2) modification of target PBPs, (3) impaired penetration of drug to target PBPs, and (4) efflux (Katzung et al 2012).…”

Zinc Oxide Quantum Dots May Provide a Novel Potential Treatment for Antibiotic-Resistant Streptococcus agalactiae in Lama glama

“…The resulting analysis revealed the presence of several virulence genes, including hylB , cfb , sip , and bibA . Among these genes, hylB is particularly important as it plays a crucial role in invading the host and evading host immunity [ 30 ]. hylB ’s primary mechanism is related to the degradation of hyaluronic acid, which enables the colonization and invasion of pathogenic bacteria at the epithelial barrier, thereby contributing to the pathogenesis of infection [ 31 ].…”

Antimicrobial resistance and virulence genes of Streptococcus agalactiae isolated from mastitis milk samples in China

“…In Shenzhen, China, 89.5–100% of S. agalactiae isolates from humans were resistant to tetracycline, and these isolates revealed their drug resistance gene spectrum to be tetO + tetM and their main virulence gene spectrum to be hylB + lmb + scpB ( 44 ). The high resistance to macrolides, lincosamides and quinolones of GBS isolates was revealed in pregnant women in southern China, and all GBS isolates harboured the hylB and cylE genes as a common virulence gene profile ( 15 ). In China, the antimicrobial-resistance and virulence gene spectra of human S. agalactiae evidenced by previous research are inconsistent with our results, and the relationship between the antimicrobial resistance and virulence of S. agalactiae is not clear and requires further exploration.…”