ANTIBIOTIC SUSCEPTIBILITIES AND PLASMID PROFILE OF EXTENDED SPECTRUM BETA LACTAMASE- PRODUCING ESCHERICHIA COLI FROM COMMUNITY ACQUIRED URINARY TRACT INFECTION AT THE UNIVERSITY OF PORT HARCOURT TEACHING HOSPITAL

Abstract

Objectives - Globally, the emergence of Extended Spectrum Beta Lactamase
(ESBL) producing Escherichia coli has been noted in community acquired
strains as against the hospital acquired origin were it was more frequent in the
past. This study was therefore designed to assess the antibiotic susceptibility
pattern of Escherichia coli; the agent commonly isolated in community
acquired urinary tract infection to the first line antibiotic in UPTH and to
determine the Extended-Spectrum Beta Lactamase producers among the
multidrug resistant E. coli strains. And to also detect plasmids associated with
ESBL production in those isolates. This will enhance targeted anti-microbial
management of community acquired UTI in University of Port Harcourt
Teaching Hospital.
Methods - Demographic data from patients suspected of having community
acquired UTI were obtained with the aid of interviewer-administered
questionnaires. Urine samples were cultured on MacConkey agar and Blood
agar plates. Gram negative isolates were identified as Escherichia coli using the
Microbact 2000 identification panel. Antibiotic susceptibility was done using
standard technique in the CLSI guideline. Plasmid extraction of multidrug
resistant Escherichia coli were done followed by agarose gel electrophoresis.
Isolates noted as harboring plasmids were subjected to plasmid curing
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procedure of Tomoeda et al. and antibiotic susceptibility pattern of the isolates
repeated. Plasmid extraction and gel electrophoresis were also repeated on
the cured isolates. Data analysis was done using Epi-info statistical software
version 3.5.2.
Results - Resistance of the isolates to the first line drugs in use in the hospital
was found to be high as over ninety percent (90.3%) of the total 392 isolates
obtained were resistant to co-trimoxazole. Others were nitrofurantoin (82.1%);
ciprofloxacin (73.5%); amoxicillin-clavulanic acid (55.1%), cefotaxime (73.5%)
and Ofloxacin (65.8%). Multidrug resistant isolate accounted for 31.6% of the
392 isolates; while 40.3% (50) of these were ESBL producers. Seventy eight
percent of the ESBL producers were found to possess plasmids ranging from
one to three with molecular weight ranging from 1.0 to 15.2 kilobase pairs.
Two percent of the ESBL positive was resistant to meropenem, a carbapenem
antibiotic.
Conclusions - ESBL producing Escherichia coli is a problem in community
acquired UTI in Port Harcourt Metropolis and they exhibit a high level of
resistance to other classes of antibiotics apart from the beta lactam drugs.
There is a need for further studies to expand the scope of antibiotics tested
and to type the ESBL plasmids that have been identified.