Prasanth Manohar1, Thamaraiselvan Shanthini2, Ramankannan Ayyanar1, Bulent Bozdogan3, Aruni Wilson4, Ashok J Tamhankar5,6, Ramesh Nachimuthu1, Bruno S Lopes2. 1. Department of Biomedical Sciences, School of Biosciences and Technology, Antibiotic Resistance Laboratory, VIT University, Vellore 632014, Tamil Nadu, India. 2. School of Medicine, Medical Sciences and Nutrition, Medical Microbiology, University of Aberdeen, Aberdeen, UK. 3. Medical Microbiology Department, Adnan Menderes University, Aydin 09100, Turkey. 4. Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, CA 92350, USA. 5. Department of Public Health Sciences, Global Health, Health Systems and Policy: Medicines in the health system - focusing antibiotics, Karolinska Institutet, Stockholm, Sweden. 6. Department of Environmental Medicine, Indian Initiative for Management of Antibiotic Resistance, Ruxmaniben Deepchand Gardi Medical College, Ujjain, India.
Abstract
PURPOSE: The occurrence of carbapenem- and colistin-resistance among Gram-negative bacteria is increasing worldwide. The aim of this study was to understand the distribution of carbapenem- and colistin-resistance in two areas in Tamil Nadu, India. METHODOLOGY: The clinical isolates (n=89) used in this study were collected from two diagnostic centres in Tamil Nadu, India. The bacterial isolates were screened for meropenem- and colistin-resistance. Further, resistance genes blaNDM-1, blaOXA-48-like, blaIMP, blaVIM, blaKPC, mcr-1 and mcr-2 and integrons were studied. The synergistic effect of meropenem in combination with colistin was assessed. RESULTS: A total of 89 bacterial isolates were studied which included Escherichia coli (n=43), Klebsiella pneumoniae (n=18), Pseudomonas aeruginosa (n=10), Enterobacter cloacae (n=6), Acinetobacter baumannii (n=5), Klebsiella oxytoca (n=4), Proteus mirabilis (n=2) and Salmonella paratyphi (n=1). MIC testing showed that 58/89 (65 %) and 29/89 (32 %) isolates were resistant to meropenem and colistin, respectively, whereas 27/89 (30 %) isolates were resistant to both antibiotics. Escherichia coli, K. pneumoniae, K. oxytoca, Pseudomonas aeruginosa, and Enterobacter cloacae isolates were blaNDM-1-positive (n=20). Some strains of Escherichia coli, K. pneumoniae and K. oxytoca were blaOXA-181-positive (n=4). Class 1, 2 and 3 integrons were found in 24, 20 and 3 isolates, respectively. Nine NDM-1-positive Escherichia coli strains could transfer carbapenem resistance via plasmids to susceptible Escherichia coli AB1157. Meropenem and colistin showed synergy in 10/20 (50 %) isolates by 24 h time-kill studies. CONCLUSION: Our results highlight the distribution of carbapenem- and colistin-resistance in Gram-negative bacteria isolated from the Tamil Nadu region in South India.
PURPOSE: The occurrence of carbapenem- and colistin-resistance among Gram-negative bacteria is increasing worldwide. The aim of this study was to understand the distribution of carbapenem- and colistin-resistance in two areas in Tamil Nadu, India. METHODOLOGY: The clinical isolates (n=89) used in this study were collected from two diagnostic centres in Tamil Nadu, India. The bacterial isolates were screened for meropenem- and colistin-resistance. Further, resistance genes blaNDM-1, blaOXA-48-like, blaIMP, blaVIM, blaKPC, mcr-1 and mcr-2 and integrons were studied. The synergistic effect of meropenem in combination with colistin was assessed. RESULTS: A total of 89 bacterial isolates were studied which included Escherichia coli (n=43), Klebsiella pneumoniae (n=18), Pseudomonas aeruginosa (n=10), Enterobacter cloacae (n=6), Acinetobacter baumannii (n=5), Klebsiella oxytoca (n=4), Proteus mirabilis (n=2) and Salmonella paratyphi (n=1). MIC testing showed that 58/89 (65 %) and 29/89 (32 %) isolates were resistant to meropenem and colistin, respectively, whereas 27/89 (30 %) isolates were resistant to both antibiotics. Escherichia coli, K. pneumoniae, K. oxytoca, Pseudomonas aeruginosa, and Enterobacter cloacae isolates were blaNDM-1-positive (n=20). Some strains of Escherichia coli, K. pneumoniae and K. oxytoca were blaOXA-181-positive (n=4). Class 1, 2 and 3 integrons were found in 24, 20 and 3 isolates, respectively. Nine NDM-1-positive Escherichia coli strains could transfer carbapenem resistance via plasmids to susceptible Escherichia coli AB1157. Meropenem and colistin showed synergy in 10/20 (50 %) isolates by 24 h time-kill studies. CONCLUSION: Our results highlight the distribution of carbapenem- and colistin-resistance in Gram-negative bacteria isolated from the Tamil Nadu region in South India.
Authors: Runze Li; Umang Goswami; Maria King; Jie Chen; Thomas C Cesario; Peter M Rentzepis Journal: Proc Natl Acad Sci U S A Date: 2018-01-08 Impact factor: 11.205
Authors: Maya L Nadimpalli; Sara J Marks; Maria Camila Montealegre; Robert H Gilman; Monica J Pajuelo; Mayuko Saito; Pablo Tsukayama; Sammy M Njenga; John Kiiru; Jenna Swarthout; Mohammad Aminul Islam; Timothy R Julian; Amy J Pickering Journal: Nat Microbiol Date: 2020-05-25 Impact factor: 17.745