VIRULENCE FACTORS CORRELATION AMONG AmpC AND ESBL PRODUCING Klebsiella pneumoniae CLINICAL ISOLATES
B. ADITI PRIYADARSHINI
Department of Microbiology, Bharath Institute of Higher Education and Research, Selaiyur, Chennai-73, India.
KRISHNAN MAHALAKSHMI
Department of Microbiology, Sree Balaji Dental College and Hospital, Chennai- 100 India.
*Author to whom correspondence should be addressed.
Abstract
Introduction: Multi drug resistant Klebsiella pneumoniae is a major threat to public health. AmpC beta lactamases and extended spectrum beta lactamases (ESBL) producing Klebsiella pneumoniae isolates hydrolyze the commonly used cephalosporin group of antibiotics rendering them ineffective in curbing the infections. Capsule lipopolysaccharides, fimbriae, siderophores and adhesions are major virulence factors in pathogenicity of K. pneumoniae. Our study aimed at evaluating the relationship between virulence and antibiotic resistance in the K. pneumoniae clinical isolates.
Materials and Methods: A total of 234 K. pneumoniae isolates were collected from a tertiary care hospital. Antibiotic susceptibility testing was performed by Vitek 2 systems version 7.0. Phenotypic screening for AmpCs and ESBLs was done using discs of cefotetan and ceftriaxone with and without phenylboronic acid. A total of eight virulence genes (uge, iutA, wabG, ycfM, fimH, entB, mrkD and iroN) were detected by multiplex PCR.
Results: Out of 87 K. pneumoniae clinical isolates 24 (27.5%) were ESBL producers, 14 (16.09%) were AmpC producers and 19 (21.8%) isolates produced both ESBL and AmpC. Uge and mrkD were the two most common virulence genes detected in our study. There were no significant correlation between antibiotic resistant enzymes production and the presence of virulence genes viz., uge, iutA, wabG, ycfM, fimH, entB, mrkD, iroN.
Conclusion: The current study reveals uge and mrkD as prime virulence genes in K. pneumoniae isolates. Significant difference was not obseved in virulence genes expression between beta lactamase producers and non producers.
Keywords: AmpC, extended spectrum beta lactamases, mrkD, uge, virulence.