Antibiotic Resistance Profiles of Pseudomonas aeruginosa Isolated from Tertiary Hospitals in Dar es Salaam, Tanzania

Abstract

Background: Healthcare-associated infections (HAIs) are a significant global concern due to their contribution in mortality and morbidity. Individuals with recent antibiotic exposure or indwelling medical devices are particularly vulnerable to these infections, especially those caused by drug-resistant bacteria like Pseudomonas aeruginosa. This bacterium presents a formidable challenge to treatment due to its resistance to multiple antibiotics.
Materials and methods: 129 Pseudomonas aeruginosa isolates were isolated from hospital environmental swabs and water samples. Antimicrobial susceptibility testing was performed by disk diffusion and five resistant genes corresponding to each antibiotic class were screened by PCR.
Results: The antibiotic susceptibility testing results indicated a significant low level of resistance among the isolated Pseudomonas aeruginosa as they were highly resistant to aztreonam with only 11.6% and less resistant to norfloxacin, amikacin and ciprofloxacin with 2.3%, 3.1% and 3.1% respectively. The strong positive correlation (r=0.83) was found between phenotypic and genotypic agreement, while the most common resistance gene was blaVIM (100%). The study also found the presence of 3 multidrug-resistant isolates that resisted fluoroquinolones, aminoglycosides, third-generation cephalosporin and Monobactam.
Conclusion: This study highlights the presence of Pseudomonas aeruginosa in hospital environments and its alarming resistance to certain antibiotics, thus emphasizing the necessity of cautious antibiotic use and management.