Detection of Extended�spectrum Beta Lactamase in Bacteria isolated from urine of pregnant women

Abstract

The aim of this study was to detect extended spectrum ?-lactamase (ESBL) in bacteria isolated from urine collected from urinary tract of infected pregnant women. A total of 100 midstream urine samples were collected from Omdurman Military Hospital from April to May2013. Specimens were cultured onto cysteine- lactose- electrolyte-deficient (CLED) agar to identify urinary tract infection (UTI) causative bacteria by colonial morphology, Gram reaction and conventional biochemical tests. Out of 100 urine specimen; 56(56%) of samples gave significant bacterial growth (the Gram negative bacilli were 42(75%). The most frequent Gram negative were Klebsiella oxytoca 15 (26.8%) and Escherichia coli 10(17.9%), while the most abundant Gram positive was Staphylococcus saprophyticus. In The susceptibility test, 5 isolates were resistant to 3rdgeneration cephalosporins (ceftazidime, ceftriaone and cefotaxime) as follow: 2 K. pneumoniae, 2 E. coli and 1 Proteus vulgaris. ESBL production test done for all bacterial resistance to 3rd generation cephalosporin and then confirmed by combination test by using Double disc synergy test 5(11.9% ) isolates gave positive result. The PCR was done for 5 isolates using TEM, SHV, and CTX-M primers.TEM gene was the most predominant one followed by CTX-M and the least one was SHV gene. From the results it could be concluded that these genes are responsible for the resistance of cephalosporins.