Full Length Research Paper

Antimicrobial resistance pattern of plasmid-mediated extended-spectrum b-lactamase producing strains of Escherichia coli

I. R. Iroha¹, A. E. Oji¹ and C. O. Esimone²

¹Department of Applied Microbiology, Ebonyi State University P. M. B 053, Abakaliki, Nigeria.

²Department of Pharmaceutics, University of Nigeria, Nsukka, Nigeria.

*Corresponding author. E-mail: ifynero@yahoo.com.

Accepted 20 June, 2008.

   Abstract

One hundred and twenty three clinical isolates of Escherichia coli isolated from Eastern Medical Hospital Enugu from blood (79) and urine (44) were bacteriologically analyzed for extended spectrum b-lactamase enzyme (ESBL) expression using double disc synergy testing method. Confirmed ESBL producing isolates were screened with nineteen different conventional antibiotics from different classes using reference agar diffusion method as described by the National Committee for Clinical Laboratory Standards (NCCLS) to determine their resistance patterns. ESBL production were detected in 21 (17.0%) of the clinical isolates of E. coli from blood while 10 (8.1%) where from blood samples. In all 31 (25.2%) of clinical isolates from blood and urine produces ESBL phenotypically. The resistance profile studies showed that the ESBL producing organisms were multi-drug resistant and the highest resistance was observed with tetracycline, erythromycin, ampicillins, cephalosporins nitrofurantoin and floroquinolones while gatifloxacin have a tremendous activity against ESBL isolates followed by augmentin.

Key words: ESBL, clinical isolates, antimicrobial resistance.