Virulence characterization of and its relation with ESBL and AmpC beta-lactamase associated resistance.

Background And Objectives: Trend analysis reveals that has witnessed a steep enhancement in the antibiotic resistance and virulence over the last few decades. The present investigation aimed at a comprehensive approach investigating antibiotic susceptibility including, extended spectrum beta-lactamase (ESBL) and AmpC β-lactamase (AmpC) resistance and the prevalence of virulence genes among the isolates.

Materials And Methods: Sixty-one isolates were obtained from various clinical infections. Antimicrobial susceptibility was performed by disk diffusion method. The Mast® D68C test detected the presence of ESBLs and AmpCs phenotypically, and later presence of ESBL and AmpC genes was observed by polymerase chain reaction (PCR). Multiplex-PCR was performed to investigate various virulence genes.

Results: Amongst 61 isolates, 59% were observed as ESBL and 14.7% as AmpC producers. All ESBL producers were positive for , while was observed in 54.1% isolates. The frequency of AmpC genes was as follows: (60.7%) and (34.4%). The most frequent virulence genes were those encoding enterobactin and lipopolysaccharide. Presence of was associated with gene, while significantly (p≤0.05) correlated with the presence of and virulence genes. positive isolates had urine as a significant source, while positive isolates were mainly collected from wound exudates (p≤0.05).

Conclusion: Our results highlight that ESBL and AmpC production along with a plethora of virulence trait on should be adequately considered to assess its pathogenesis and antibiotic resistance.