Journal of Laboratory Physicians
Home About us Ahead of print Current issue Back issues Subscribe Instructions Contact Login 
Wide layoutNarrow layoutPrint this page  Email this page Bookmark this page Small font size Default font size Increase font size 
 
ORIGINAL ARTICLE
Year : 2017  |  Volume : 9  |  Issue : 2  |  Page : 81-83

Comparison of four phenotypic methods for detection of metallo-β-lactamase-producing Gram-negative bacteria in rural teaching hospital


1 Department of Microbiology, GMERS Medical College, Gotri, Gujarat, India
2 Department of Microbiology, CU Shah Medical College and Hospital, Surendranagar, Gujarat, India

Correspondence Address:
Sweta Sunil Oza
Department of Microbiology, C.U. Shah Medical College and Hospital, Surendranagar, Gujarat - 363 001
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0974-2727.199624

Rights and Permissions

Context: Metallo-β-lactamase (MBL)-producing bacteria lead to resistance to carbapenem an antibiotic that used as the last resort for treatment of multidrug-resistant bacteria, extended spectrum beta-lactamases, and AmpC β-lactamase-producing Gram-negative bacteria (GNB). The emergence of MBL-producing GNB is challenge to microbiology laboratories because there are no standardized guidelines available to detect them. The aim of this study was to compare four phenotypic methods to detect MBL production in GNB and to determine antibiotic sensitivity of MBL-producing isolates. Materials and Methods: A total of 107 clinical isolates of GNB were tested for MBL production. Imipenem (IPM)-resistant GNB were taken as positive for MBL screening. MBL detection was done using ethylene diamine tetra acetic acid (EDTA) as MBL inhibitor. Four phenotypic methods were evaluated: (1) Combined disk synergy test (CDST) with 0.5M EDTA (CDST-0.5 M EDTA), (2) CDST with 0.1 M EDTA (CDST-0.1 M EDTA), (3) double-disk synergy test (DDST) with 0.5M EDTA (DDST-0.5 M EDTA), and (4) DDST with 0.1 M EDTA (DDST-0.1 M EDTA). Results: Out of 107 GNB, 30 were resistant to IPM considered as screening positive. Out of 30, 21 (70%) isolates were MBL positive by CDST-0.1 M EDTA, 19 (63.33%) by CDST-0.5M EDTA, 17 (56.67%) by DDST-0.1 M EDTA, and 16 (53.33%) by DDST-0.5M EDTA. All MBL-producing Gram-negative Bacilli were resistant to ampicillin/sulbactam. Polymyxin B was found to be the most sensitive drug. Conclusion: CDST-0.1 M EDTA is the most sensitive method MBL detection. The detection of MBL-producing GNB is very important to control spread of the resistance.


[FULL TEXT] [PDF]*
Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)
 

 Article Access Statistics
    Viewed58    
    Printed3    
    Emailed0    
    PDF Downloaded12    
    Comments [Add]    

Recommend this journal