Isolation and molecular characterization of New Delhi metallo-beta-lactamase-1 producing superbug in Bangladesh

  • Refath Farzana Dhaka Medical College, Department of Microbiology, Dhaka, Bangladesh
  • SM Shamsuzzaman Dhaka Medical College, Department of Microbiology, Dhaka, Bangladesh
  • Kazi Zulfiquer Mamun Dhaka Medical College, Department of Microbiology, Dhaka, Bangladesh
Keywords: metallo-beta-lactamase, New Delhi metallo-beta-lactamase-1, Bangladesh, molecular characterization, antimicrobial susceptibility patterns

Abstract

Introduction: New Delhi metallo-beta-lactamse-1 (NDM-1) producing superbugs create a global public health problem because of their resistance to most antibiotics. This study was conducted to determine the presence of MBL producers, including NDM-1 producers, in Bangladesh, along with the antimicrobial resistance patterns of these organisms.

Methodology: Thirty-five isolates resistant to imipenem by disk diffusion technique were investigated for MBL production. Minimum inhibitory concentration (MIC) of imipenem was determined by agar dilution method. MBL producers were phenotypically detected by double disk synergy test and combined disk assay. Gene encoding blaIMP-1, blaIMP-2, blaVIM-1, blaVIM-2, blaNDM-1 and class 1 integron was identified by PCR.

Results: Thirty-one (88.57%) MBL producers were detected by PCR, 24 (68.57%) by double disk synergy test, and 30 (85.71%) by combined disk assay. Eight (22.86%) were positive for blaNDM-1, 13 (37.15%) for blaVIM-1, 21 (60.00%) for blaVIM-2, 18 (51.43%) for blaIMP-1, and 9 (25.71%) for blaIMP-2. More than one blaMBL was present in 23 (65.71%) of the isolates. MIC of imipenem of MBL producers ranged from ≥256 µg/ml to ≤8 µg/ml. All the NDM-1 producing isolates carried class 1 integron. NDM-1 producers were 100% resistant to amoxicillin, cephradine, cefuroxime, ceftazidime, cefotaxime, ceftriaxone, aztreonam, gentamicin and piperacillin, 87.5% to amikacin, 75% to ciprofloxacin, and 62.5% to co-trimoxazole and the combination of tazobactam and piperacillin. All were sensitive to colistin.

Conclusion: The results of this study provide insight into the presence of blaMBL, including blaNDM-1, in Bangladesh. Urgent epidemiological monitoring of MBL producers in Bangladesh may combat their rapid dissemination.

Author Biographies

Refath Farzana, Dhaka Medical College, Department of Microbiology, Dhaka, Bangladesh

Research student in Department of Microbiology,

Dhaka Medical College, Dhaka.

SM Shamsuzzaman, Dhaka Medical College, Department of Microbiology, Dhaka, Bangladesh

Associate Professor in Department of Microbiology,

Dhaka Medical College, Dhaka.

 

Kazi Zulfiquer Mamun, Dhaka Medical College, Department of Microbiology, Dhaka, Bangladesh

Professor in Department of Microbiology,

Dhaka Medical College, Dhaka.

Published
2013-03-14
How to Cite
1.
Farzana R, Shamsuzzaman S, Mamun KZ (2013) Isolation and molecular characterization of New Delhi metallo-beta-lactamase-1 producing superbug in Bangladesh. J Infect Dev Ctries 7:161-168. doi: 10.3855/jidc.2493
Section
Emerging Problems in Infectious Diseases