Phenotypic and molecular investigation of antibiotic resistance pattern and molecular typing of non-fermentingbacteria isolated from blood cultures of patients admitted to Mofid Hospital

Introduction: Bacteremia, indicating the presence of bacteria in the bloodstream, is a critical health issue thatcan cause significant morbidity and economic burden. This study focuses on the phenotypic and molecularcharacteristics of antibiotic-resistant non-fermenting bacteria isolated from blood cultures of patients at MofidHospital.Methodology: Blood cultures from hospitalized patients were collected and cultured on blood agar andMacConkey agar. After incubation at ۳۷°C, colony morphology was assessed, followed by Gram staining.Biochemical tests, such as TSI and SIM, identified Pseudomonas aeruginosa and Acinetobacter baumannii.Antibiotic susceptibility was determined using the CLSI ۲۰۲۳ guidelines on Mueller-Hinton agar. For molecularanalysis, DNA was extracted using the boiling method, and PCR was performed to detect resistance genes.Discussion: The study highlighted the prevalence of antibiotic resistance among non-fermenting bacteria. Themolecular typing revealed the presence of specific resistance genes, indicating a potential for horizontal genetransfer. The findings underscore the importance of stringent infection control measures and routinesurveillance to manage and mitigate the spread of resistant strains.Conclusion: This investigation underscores the critical need for continuous monitoring of antibiotic resistancepatterns in clinical settings. The identified resistance genes necessitate enhanced infection control protocols toprevent the dissemination of these resistant bacteria in hospital environments. Further research should exploreadvanced molecular techniques to better understand the mechanisms driving resistance and inform targetedtherapeutic strategies.

Keywords:

antibiotic resistance , molecular typing , non-fermenting bacteriaphenotypic and molecular investigation