DETECTION OF AMP-C BETA-LACTAMASES IN URINARY ISOLATES OF ESCHERICHIA COLI THROUGH VARIOUS PHENOTYPIC METHODS

AMP C Beta-Lactamases in Urinary Isolates of Escherichia Coli

Abstract

Objective: To determine the prevalence of Amp C beta lactamases in urinary isolates of Escherichia coli (E. coli),
and to evaluate and compare different phenotypic methods for its detection in a cost effective way.
Study Design: Descriptive study.
Place and Duration of Study: Department of Microbiology, Combined Military Hospital Lahore Pakistan, from
Jan 2016 to Jun 2016.
Material and Methods: Modified Three Dimensional Test (M3DT) taken as Gold standard, Modified Hodge Test
(MHT) (Cefoxitin), Nitrocephin test and three screening strategies for the detection of Amp C Beta-lactamases
were tested on urinary isolates of E. coli collected during a period of 06 months.
Results: Modified Hodge Test, was found to be simple, highly specific and sensitive in detecting these enzyme
producers. Collectively these tests detected 45.07% of E. coli to be Amp C producers.
Conclusion: Each of the three tests can be used as an acceptable phenotypic confirmatory tool when Amp C production
in E. coli is suspected.