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Co-production of NDM-1with OXA-48 in urinary isolates of E. coli was detected for the first time in India. Transmission of plasmid carrying these resistant genes to other members of Enterobacteriaceae will increase incidence of multidrug resistance. Early detection of these genes will help in prevention and adequate infection control by limiting the spread of these organisms.

Objective: The present study was undertaken to detect the prevalence of the bla NDM-1 metallo beta lactamases (MBLs) in the isolates of Pseudomonas aeruginosa, which were recovered from various clinical samples from hospitalized patients in a tertiary care centre in Pune, India. Methods:A total of 200 isolates of P. aeruginosa which were obtained from various clinical samples were subjected to antibiotic susceptibility testing by the disc-diffusion method and their MICs were determined by the Vitek -2 Automated Antimicrobial Identification and Susceptibility Testing System against imipenem, meropenem, ticarcillin, amikacin, gentamicin, tobramycin, ciprofloxacin, levofloxacin, moxifloxacin, tigecycline, trimethoprim/sulfamethoxazole, ampicillin/sulbactam, piperacillin/ tazobactam, cefoperazone/sulbactam, cefepime, tetracycline, ceftazidime, ceftriaxone and colistin. Their MICs were also determined by the Etest method against imipenem, meropenem, piperacillin, tobramycin, ceftazidime, tigecycline and colistin. The presence of bla NDM-1 was detected by PCR and it was confirmed by sequencing the gene which was present in the isolates which exhibited carbapenem resistance. The experimental transferability of the plasmids which carried bla NDM-1 was determined by using E. coli J53 as the recipient. Result:In the present study, four isolates of P. aeruginosa, which carried the bla NDM-1 gene, were resistant to imipenem and meropenem. These bla NDM-1 carrying isolates remained susceptible to colistin. The plasmid carrying bla NDM-1 was successfully transferred from the four isolates to E. coli J53 recipients. Conclusions:We are reporting the emergence of the P. aeruginosa carrying NDM-1gene, which exhibited resistance to imipenem and meropenem, for the first time from India.

Objective. To detect genes encoding carbapenem resistance among Enterobacter species in a tertiary care hospital in central India. Methods. Bacterial identification of Enterobacter spp. isolates from various clinical specimens in patients admitted to intensive care units was performed by routine conventional microbial culture and biochemical tests using standard recommended techniques. Antibiotic sensitivity test was performed by standard Kirby Bauer disc diffusion technique. PCR amplification and automated sequencing was carried out. Transfer of resistance genes was determined by conjugation. Results. A total of 70/130 (53.84%) isolates of Enterobacter spp. were found to exhibit reduced susceptibility to imipenem (diameter of zones of inhibition ≤13 mm) by disc diffusion method. Among 70 isolates tested, 48 (68.57%) isolates showed MIC values for imipenem and meropenem ranging from 32 to 64 mg/L as per CLSI breakpoints. All of these 70 isolates were found susceptible to colistin in vitro as per MIC breakpoints (<0.5 mg/L). PCR carried out on these 48 MBL (IP/IPI) E-test positive isolates (12 Enterobacter aerogenes, 31 Enterobacter cloacae, and 05 Enterobacter cloacae complex) was validated by sequencing for beta-lactam resistance genes and result was interpreted accordingly. Conclusion. The study showed MBL production as an important mechanism in carbapenem resistance in Enterobacter spp. and interspecies transfer of these genes through plasmids suggesting early detection by molecular methods.

Objective: To detect genes encoding carbapenem resistance in Acinetobacter baumannii in an intensive care unit. Methods

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b E nterobacter spp. have emerged as pathogens responsible for hospital-acquired infections. Carbapenem resistance is increasingly being reported in this species, which is a matter of concern. Enterobacter spp. can produce abdominal, urinary tract, meningeal, and surgical site infections. In the present study, we report a case of Enterobacter ludwigii infection in a 17-year-old female who underwent surgery for an aneurysmal bone cyst in her left distal femur. She was treated with intravenous cefotaxime and amikacin postoperatively. She developed a purulent discharge from the surgical site after 72 h of surgery. Microbiological culture of the purulent material on two consecutive days grew a Gramnegative, motile bacillus in pure culture, which was identified to the species level as Enterobacter ludwigii by its growth on myoinositol and 3-0-methyl-D-glucopyranose and then phenotypically confirmed by the Vitek-2 test (bioMérieux, Marcy l'Etoile, France). The antibiotic susceptibility test was performed by the disc diffusion method as per Clinical and Laboratory Standards Institute (CLSI) (1) guidelines using commercial antibiotic discs (Hi Media, Mumbai, India). MICs of antibiotics were determined by Vitek-2 per CLSI breakpoints (Table 1). MICs of meropenem and imipenem determined by the Etest were Ͼ32 g/ml for the isolate. The production of metallo-␤-lactamase (MBL) was confirmed by positive results from the double-disc synergy test, modified Hodge test, combined-disc synergy test, and MBL (IP/IPI) Etest method (bioMérieux, Marcy l'Etoile, France). PCR-based screening for beta-lactamase genes (bla CTXM , bla SHV , bla TEM , and bla OXA ) and the Ambler class (B and D) carbapenemase genes bla IMP , bla VIM , bla SPM , bla GIM , bla SIM , bla NDM-1 , bla OXA-23 , bla , and bla OXA48 gave positive results for bla NDM-1 , bla CTX-M-15 , bla OXA-2 , and bla OXA-48 (2-5), confirmed by sequencing. 16S rRNA gene sequence analysis showed a sequence identity value of 99% with GenBank accession number KC139450. PCR primers were procured from Sigma-Aldrich, India. Plasmid analysis using the Kieser technique (6) revealed that E. ludwigii harbored three plasmids, with sizes of 130, 50, and 35 kb. Conjugation using E. coli J53 (azide resistant) as the recipient strain revealed the bla NDM-1 gene to be present on a 130-kb plasmid. Using the PCRbased replicon typing (PBRT) (7) method, we identified an IncA/C type (amplicon size of 465 bp) that was cotransferred with two other plasmids of 35 and 50 kb. The bla CTX-M-15 gene together with bla OXA-2 was identified on the 35-kb plasmid, which belonged to the IncFIB type and had an amplicon size of 702 bp. The bla OXA-48 gene was identified on a 50-kb plasmid that belonged to the IncFIA type and had an amplicon size of 462 bp. Although the coexistence of bla NDM-1 with different carbapenemase genes has been reported, we believe this to be the first report of the cooccurrence of bla NDM-1 and bla OXA-48 in a clinical isolate of E. ludwigii from central India. The growing emergence of ca...

Co-production of NDM-1 with CTX-M-15 in K. pneumoniae isolates was detected for the first time in our NICU. Transmission of plasmid carrying these resistant genes to other members of Enterobacteriaceae will increase the incidence of multidrug resistance. Early detection of these genes will help in prevention and adequate infection control by limiting the spread of these organisms.