Community Acquired Infection

ORIGINAL ARTICLE
Year
: 2015  |  Volume : 2  |  Issue : 2  |  Page : 57--62

Detection of ESBL and plasmid-mediated AmpC beta lactamases among the Gram-negative bacterial isolates in diabetic foot ulcer infections


Chittur Yerat Ranjini1, Vidhya Rani Rangasamy2 
1 Department of Microbiology, Vydehi Institute of Medical Sciences and Research Centre, Bangalore, Karnataka, India
2 Department of Microbiology, Government Dharmapuri Medical College, Dharmapuri, Tamil Nadu, India

Correspondence Address:
Chittur Yerat Ranjini
A G 11, DSR Sunshine Apartments, Krishna Reddy Layout, 1st Main, Banaswadi, Bangalore - 560 043, Karnataka
India

Background and Aim: Foot ulcers are a significant complication of diabetes mellitus and are usually poly-microbial. Aerobic Gram-negative bacilli are isolated in higher frequency with increasing grade of ulcers, and development of drug resistance is a cause of concern. The aim of our study is to identify the extended spectrum β-lactamases (ESBL) and AmpC β-lactamases among the Gram-negative aerobic bacterial isolates in the different grades of diabetic foot ulcers. Materials and Methods: Pus samples from 104 male and female diabetic patients presenting with grade I to grade V foot ulcers were cultured according to the standard microbiological procedures and antimicrobial sensitivity performed by the Kirby-Bauer disc diffusion method as per CLSI guidelines. MIC 50 of all isolates for Ceftazidime was detected by the agar dilution method. The Gram-negative bacterial isolates were further tested for ESBL and AmpC β-lactamases by the modified double disc synergy test and combined disc method. AmpC disc test was used for the confirmation of AmpC production. Results: Forty-seven isolates exhibited resistance to Ceftazidime phenotypically and 54 isolates had MIC greater than 2 μg/mL. ESBL production was observed in 55.55% of the isolates. AmpC production was seen in 19 isolates (35.18%). No mechanism of cephalosporin resistance was explainable for 5 isolates. Conclusion: The combined disc method was more sensitive in the detection of ESBLs, while the AmpC disc test was an easy way to detect AmpC beta lactamases and can be used for routine screening.


How to cite this article:
Ranjini CY, Rangasamy VR. Detection of ESBL and plasmid-mediated AmpC beta lactamases among the Gram-negative bacterial isolates in diabetic foot ulcer infections.Community Acquir Infect 2015;2:57-62


How to cite this URL:
Ranjini CY, Rangasamy VR. Detection of ESBL and plasmid-mediated AmpC beta lactamases among the Gram-negative bacterial isolates in diabetic foot ulcer infections. Community Acquir Infect [serial online] 2015 [cited 2022 Jan 19 ];2:57-62
Available from: http://www.caijournal.com/article.asp?issn=2225-6482;year=2015;volume=2;issue=2;spage=57;epage=62;aulast=Ranjini;type=0