We aimed in our work to screen ESBL producing E.coli in UTI and
detection of O25-ST131clone in ESBL producing E.coli with
fluoroquinolone resistance. This study was carried out in the Clinical
Microbiology Laboratory at Kasr El Aini Hospital, Faculty of Medicine,
Cairo University, Egypt,

We aimed in our work to screen ESBL producing E.coli in UTI and
detection of O25-ST131clone in ESBL producing E.coli with
fluoroquinolone resistance. This study was carried out in the Clinical
Microbiology Laboratory at Kasr El Aini Hospital, Faculty of Medicine,
Cairo University, Egypt, during 10 months from November 2010 to August
2011, where three thousand, nine hundred and twenty two urine samples
were collected from patients with cystitis and the patients data were
collected.
All isolates were subjected to routine culture on blood agar and
MacConky agar media and incubated for 24 to 48 hrs at 35°C. Identification
of the isolates was done using Gram stain morphology and conventional
biochemical tests. Antimicrobial susceptibility testing and phenotypic
detection of ESBL production were carried on Muller-Hinton agar by using
the combination disk as recommended by CLSI, (2010) guidelines.
Identification revealed 492 E.coli isolates.

Carbapenems are a class of Beta-lactam antibiotics with broad spectrum of antibacterial 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 β-lactamases like an extended-spectrum Beta-lactamase (ESBL) or AmpC. Klebsiella pneumoniae carbapenemase (KPC) class A (serine carbapenemases is one of the most prevalent carbapenemases in Enterobacteriaceae.
In the present study, we attempted to determine the prevalence of KPC among 100 clinical isolates of Enterobacteriaceae by phenotypic confirmatory tests; the modified Hodge test (MHT) and boronic acid inhibition test and to compare both methods by PCR for blaKPC
Initial screening for carbapenemase-producing isolates among the 100 Enterobacteriaceae isolates was done using meropenem and ertapenem by disk diffusion method followed by MIC determination by E-test .Confirmation of KPC among carbapenem non-susceptible isolates was done by phenotypic methods as MHT and boronic acid inhibiton test and by genotypic methods as PCR.
The Results of this study showed that the prevalence of carbapenemase producing isolates by MHT was 51% and prevalence of KPC by carbapenem-boronic acid combined disk test was 35%, while it was 49% by genotypic method.
Key words: Enterobacteriaceae, Klebsiella pneumonia carbapenemase, modified Hodge test, boronic acid.