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, Nigeria

Abstract

Background: 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. This study was designed to assess 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. Methods: Demographic data from patients suspected of having community acquired UTI were obtained with the aid of questionnaires. Urine samples were cultured on MacConkay agar and Blood agar plates. Gram negative isolates were identified as Escherichia coli using the MicrobactTM 12A GNB identification system. Antibiotic susceptibility was done following standard technique in the CLSI guideline. Plasmid extraction of multidrug resistant Escherichia coli were done followed by agarose gel electrophoresis. Isolates harboring plasmids were subjected to plasmid curing procedure of Tomoeda et al. and antibiotic susceptibility pattern 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 high; as 90.3% of the total 392 isolates were resistant to co-trimoxazole. Nitrofurantoin (82.1%); ciprofloxacin (73.5%); amoxicillin-clavulanic acid (55.1%), cefotaxime (73.5%) and ofloxacin (65.8%). ESBL production was detected in 40.3% (50) while 78% 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: There was a high level of resistance to the first line drugs. High molecular weight plasmids were detected and were responsible for conferring resistance to other group of antibiotics.