Occurrence and detection of Carbapenemase-Producing Klebsiella pneumoniae clinical isolates in Najaf Hospitals

Abstract EN

Resistance to carbapenems is emerging, and it is a great problem to therapeutics.

Carbapenemase producing Klebsiella pneumoniae have been reported to be important cause of nosocomial infections.

There is no information available on carbapenemase producing K.

pneumoniae from Najaf.

The purpose of this study was undertaken to determine the occurrence of carbapenmase including metallo β-lactamases (MBLS), Klebsiella pnuemoniae carbapenemase (KPC) and GES-β-lactamase producing K.

pneumoniae.

A total of 770 clinical samples were collected from April to July, 2010.

The K.

pneumoniae isolates were identified according to API 20E system.

Phenotypic detection of carbapenemase was performed by using the imipenem-EDTA disk method and confirmed by the modified Hodg test.

KPC was detected on KPC CHROMagar medium.

The isolates were subjected to polymerase chain reaction (PCR) assays with specific primers for blaIMP, blaVIM blaKPC.

blaCTX-M and blaAmpC.

Only 108 (14.%) K.

pneumoniae isolates were recovered from clinical infections.

only 95 (88%) isolates were β-lactam resistant (resistant to both ampicillin and amoxicillin).

Of the β-lactam resistant isolates, 4/95 (4.2%) were found to be carbapenem disk resistant, of which,2 (50%) gave positive result with the imipenem-EDTA test, 4 (100%) gave positive result with modefied Hodg test and all isolates (100%) gave heavy growth on KPC CHROMagar.

In PCR experiments using specific primers for blaIMP, blaVIM and blaKPC genes, the results were negative among all isolates.

All isolate were harbored blaCTX-M and blaAmpC genes.

The present findings suggest that the spread of carbapenemases in isolates is high in Najaf.