Journal of Pure and Applied MicrobiologyVol. 11 No. 4

Detection of Carbapenemase-producing Enterobacteriaceae using Chromogenic Medium, ChromidID OXA-48, in Critical Care Patients of Kasr Al-Ainy Hospital in Egypt

Basma A. El Awady1*, Mera G. Anan1, Hamida A. Gohar1 and Mohamed H. Saleh2

1Department of Medical Microbiology and Immunology, Faculty of Medicine, Cairo University, Cairo, Egypt. 2Department of Critical Care, Faculty of Medicine, Cairo University, Cairo, Egypt.

Received on 02 October 2017 and accepted on 29 November 2017

 

ABSTRACT

Carbapenems are a class of beta-lactam antibiotics with broad spectrum of activity. They are often considered as a last resort in treatment of infections caused by multidrug resistant organisms. Carbapenemase-producing Enterobacteriaceae (CPE) have been reported worldwide. Resistance to carbapenems in Enterobacteriaceae is caused mainly by carbapenemase production or by porin loss combined with the expression of -lactamases like extended-spectrum beta-lactamases (ESBL) or AmpC -lactamase. Class D OXA-48 carbapenemases is one of the most prevalent carbapenemases in Enterobacteriaceae. In the present study, we attempted to isolate carbapenemase-producing Enterobacteriaceae from different clinical specimens obtained from hospitalized patients at different ICU of kasr Al-Ainy hospital. Initial screening for carbapenemase-producing Enterobacteriaceae was done using ertapenem disc diffusion method and direct inoculation of the specimens into ChromID OXA-48. The phenotypic Modified Hodge Test (MHT) was used for confirmation of carbapenemse production among screened carbapenem resistant isolates.Out of 112 collected samples, 94 Enterobacteriaceae were isolated. Fifty five isolates (58.5%) were ertapenem disc resistant and 50 isolates (53%) showed positive growth on ChromID OXA-48. Fifty two (94.5%) out of 55 suspected carbapenemase-producing isolates by disc diffusion method and the 50 isolates (100%) grown on ChromID OXA-48 were MHT positive.

Keywords : Enterobacteriaceae, class D OXA-48 carbapenemase, ChromID OXA-48, Modified Hodge Test.