Antibiotic Susceptibility Profile of Clinical Isolate of Carbapenem-Resistant Pseudomonas aeruginosa

Background and Objectives: Carbapenem-resistant Pseudomonas aeruginosa, are among the top tier of the list of antibiotic-resistant priority pathogens that pose the greatest threat to human health. In recent years, the rate of carbapenem resistance in Pseudomonas aeruginosa has increased worldwide and has become of great concern since it significantly restricts the therapeutic options for patients. Therefore this study was undertaken to determine the antibiotic susceptibility profile of the clinical isolate of Carbapenem-resistant Pseudomonas aeruginosa.

Methodology: A total of five hundred (500) clinical samples were collected from patient’s attending Alex Ekwueme Federal University Teaching Hospital Abakaliki, Ebonyi State (AFEUTHA). The collected samples were analyzed for the presence of Pseudomonas aeruginosa using standard microbiological techniques for isolation and characterization of bacteria. Further strain confirmation was performed using VITEK 2 System. Phenotypic detection of Carbapenem-resistant Pseudomonas aeruginosa was performed using Modified Hodge testing. Antibiotic susceptibility was performed by employing Kirby-Bauer disk diffusion method and the results were interpreted using the Clinical Laboratory Standard Institute (CLSI) zone diameter breakpoints.

Results: The occurrence rate of Pseudomonas aeruginosa in clinical samples accounted for 119(23.8%) consisting of a high proportion from urine sample 81(27.4%) followed by wound swabs 13(25.5%), high vaginal swabs 17(20.7) while the least occurrence rate was observed against catheter tips 5(12.8%) and sputum 3(9.4%). Modified Hodge testing revealed 31(6.2%) carbapenem-resistant Pseudomonas aeruginosa comprising of high proportion of 24(8.1%) from urine samples followed by wound swab 5(9.8%) while Carbapenem-resistant Pseudomonas aeruginosa was absent in High Vaginal Swab recording 0(0.0%). Carbapenem-resistant Pseudomonas aeruginosa isolates were highly resistant to amoxicillin-clavulanic 100%, colistin 100%, tetracycline 100%, nitrofurantoin 70.8%, aztreonam 87.5% but were susceptible to nalixidic acid 50.0 %, ofloxacin 75.0%, and ciprofloxacin 100%.

Conclusion: As in-vitro susceptibility of carbapenem-resistant Pseudomonas aeruginosa isolates to ofloxacin and ciprofloxacin is known, their judicious utilization will accelerate a significant improvement in the patient's condition. As such, there is a substantial need for the evaluation of a wide spectrum and new therapies in different classes to counteract this imminent crisis of resistance among Carbapenem-resistant Pseudomonas aeruginosa.