Desta KassuAraya ShambelAddis Tesfa2021-12-072023-11-062021-12-072023-11-062021-06http://etd.aau.edu.et/handle/123456789/29122Background: Pseudomonas aeruginosa is a common cause of nosocomial infections with associated morbidity and mortality because the organism is unresponsive to commonlyavailable antimicrobials. This study was undertaken to determine the Multiple Drug-Resistant(MDR), Extensive Drug-Resistant (XDR) and Pan Drug-Resistant (PDR) phenotype ofP.aeruginosa and its carbapenemase production rate from presumptive isolates stored in thebio-bank at the Ethiopian Public Health Institute (EPHI). Methods: A cross-sectional study was conducted at the EPHI laboratory, Addis Ababa,Ethiopia from March to June 2021. Stored isolates of Pseudomonas spp. which had beencharacterized by manual identification methods were further processed for species-levelidentification (ID) and antimicrobial susceptibility testing (AST) using a Becton Dickinson(BD) Phoenix automated system. The isolates were analyzed for carbapenemase enzymeproduction using the modified Carbapenem Inactivation Method (mCIM). The data analysiswas done using SPSS version 20 software. Results: In this study, 110 presumptive Pseudomonas isolates from a biobank were reanalyzed,100 of them were found to be Pseudomonas and among these P.aeruginosaaccounted for 98% and P.putida accounted for 2%. The majority of isolates were recoveredfrom wound (46%) specimens followed by ear swabs (18%). The highest level of resistancewas observed against Ceftazidime (35%) and the lowest level of resistance was observedagainst Amikacin (2%). Twenty-seven isolates were identified as candidates forcarbapenemase enzyme production testing, of which only 3/27 (11%) isolates were detectedas carbapenemase enzyme producers. Conclusions: This study shows an increasing rate of MDR and XDR isolates and theappearance of PDR in P.aeruginosa strain, this is a serious problem in Ethiopia. The lack ofnewer anti-pseudomonal antibiotics adds to the problem. In order to alleviate this problem, Infection prevention activities should be promoted, and treatment of bacterial infectionsshould be guided by antibiotic susceptibility test results.en-USP.aeruginosa, Antimicrobial Resistance, Carbapenemase enzyme, EthiopiaThesis