Molecular characteristics of antimicrobial resistance and biofilm formation of bloodstream infection pathogens isolated from pediatric patients in Ukraine.

OBJECTIVES

To determine antimicrobial resistance and biofilm-associated genes among clinical isolates of bloodstream infection pathogens in Ukraine.

METHODS

A total of 35 clinical strains of and 50 clinical strains of spp. were isolated from patients from Ukrainian tertiary-level children`s hospitals during 2023 with bloodstream infections including central venous catheter-associated infections. Antimicrobial susceptibility testing was conducted following the European Committee on Antimicrobial Susceptibility Testing methodology. Capacity to form biofilms was assessed using a microtiter plate assay. Amplification of the variable resistance genes () and biofilm-associated genes ( was performed by polymerase chain reaction.

RESULTS

|Overall, 96% (n = 46/50) of all Staphylococcus spp. strains expressed icaA, 94% (n = 47/50) of strains expressed fnbpA and 92% (n = 45/50) expressed clfA genes. In total, 32% (n = 16/50) of strains were resistant to methicillin, and all of the strains expressed mecA. All strains expressed , and 97% (n = 34/35) expressed and genes. All of were resistant to third-generation cephalosporins, 74.3% (n = 25/35) of isolates expressed and 80% (n = 28/35) expressed gene, 71.4% (n = 25/35) strains expressed both genes. In total, 80% (n = 28/35) of were resistant to carbapenems, 60.7% (n = 17/28) expressed , 64.3% (n = 18/28) expressed and all 28 strains expressed . A total of 90% (n = 18/20) of were resistant to fluoroquinolones, 88.9% (n = 16/18) expressed and none of the isolates expressed gene.

CONCLUSIONS

Very high prevalence of genes associated with biofilm formation was observed in clinical isolates of spp. and . High-level resistance to all antimicrobials was observed in strains.