Phenotypic and molecular characterization of clinical isolates of Acinetobacter baumannii isolated from Delhi, India

Abstract

BackgroundAcinetobacter has gained importance as a multi-drug resistant and hence a difficult to treat pathogen. This study was done to characterize our isolates with respect to drug resistance and presence of beta-lactamases which is a major mechanism of resistance and to type using RAPD and MLST so that comparison of our clones can be made with the existing international clones.Methods100 isolates recovered from clinical samples from two hospitals in Delhi were tested for their susceptibility against major groups of antimicrobials. The resistant isolates were screened and confirmed phenotypically for presence of ESBL, MBL and AmpC and MBLs also by PCR. The isolates were typed by RAPD and MLST.ResultsOut of the 100 isolates, 91, 78 and 2 % were MDR, XDR and PDR respectively. 97, 100 and 85 were screen positive for ESBL, AmpC and MBL respectively. Of these, 38.1 % were confirmed phenotypically to produce ESBL, 99 % produced AmpC and 29.4 % produced MBL comprising of GIM, VIM, SIM and IMP. MLST showed known STs 110, 188, 146, 69, 103, 108 and 194. Eight new STs were encountered. The RAPD showed a high degree of genetic variability among the isolates.ConclusionMajority of our isolates were MDR, producing one or more types of beta-lactamases. We encountered drug resistant international clones by MLST which are found in other continents there by confirming their spread to Indian sub continent. No data on ST types of other Indian isolates is available in the MLST database and hence comparison is not possible.

Molecular Study of Acinetobacter baumannii Isolates for Metallo-β-Lactamases and Extended-Spectrum-β-Lactamases Genes in Intensive Care Unit, Mansoura University Hospital, Egypt

“…The resistance of A. baumannii isolates to cephalosporins in the present study was in accordance with another study conducted by Safari et al, 2013 [5]. Ciprofloxacin resistance rate (92.9%) was similar to studies conducted in Egypt and India which showed resistance rate of 85% and 99%, respectively [22, 23]. …”

Evaluation of synergistic effect of tazobactam with meropenem and ciprofloxacin against multi-drug resistant Acinetobacter baumannii isolated from burn patients in Tehran

“…Our results indicated that all A. baumannii isolates were MDR and carbapenem resistant. The high prevalence of MDR A. baumannii strains is in accordance with the findings reported by Farsiani et al (97%) and Rynga et al (85%) in Iran and India, respectively [20], [21]. The global spread of MDR clones in healthcare settings has raised a great deal of concern, because carbapenem agents are commonly the first choice in the treatment of A. baumannii infections [22], [23].…”

Molecular Epidemiology of Metallo Beta Lactamases in Acinetobacter Baumannii at a Tertiary Care Hospital

“…Carbapenem resistance in A.baumannii has been reported in various studies, ranging from 40-98.7% (5, [21][22][23][24]. We found 86.9% carbapenem resistance in A. baumannii which is similar to 85% resistance reported by Rynga D et al (2015) from Delhi (25). But previous studies conducted in our institute by Pandya et al, (2012) and Kalpesh et al (2016) have reported a comparatively higher resistance to carbapenems i.e.…”