PREVALENCE OFEXTENDED SPECTRUM BETA LACTAMASE IN CLINICAL ISOLATES OF ESCHERICHIA COLI FROM SOME HOSPITALS IN AL?NASSIRIYAH CITY, THI ?QAR, IRAQ

A total of 50 isolates of Escherichia coli collected from clinical specimens obtained from some hospitals in Al ?Nassiriyah city, Thi ?Qar, Iraq. These isolates were tested for production of extended ?spectrum β -lactamases (ESBLs) by two ESBL phenotypic tests (ESBL screening test and confirmatory test (mDDST)). Out of 50 Escherichia coli isolates34 (68%) and 30(60%) were positive ESBLs screening test for cefotaxime and ceftazidime respectively by using disk diffusion method, 31(62%) and 36(72%) isolates were positive for cefotaxime and ceftazidime respectively by using broth dilution method (MIC?2?g). 25(50%) of isolates were positive for ESBL by using modified confirmatory test (mDDST) with extended spectrum cephalosporins (ESCs) and disk of Amc (Amoxicillin?Clavulanate). All ESBL pruducers isolates (100%) were sensitive to imipenem. ESBL producers showed a high degree resistance to cephalexin (60%), co-trimethaxazole (80%), cephalothin (92%), tetracycline (92%), cefixine (100%) and ampicillin (100%).