Pseudomonas aeruginosa and Escherichia coli are both gram negative bacteria with an incriminating epidemiology in common and vast majority of human pathogenic infections; coupled with their relatively high resistance to several antibiotics used for their treatment management. This study aimed at determining the prevalence of Pseudomonas aeruginosa and Escherichia coli from both clinical and environmental sources, and their antibiotic susceptibility pattern in relation to their plasmid profile, using standard microbiological methods. A total of 100 samples of both clinical and environmental origin were collected; ranging from urine, wound swab, water and soil. Result obtained revealed variation in the percentage prevalence of Pseudomonas aeruginosa and Escherichia coli across clinical and environmental samples; with Escherichia coli recording a higher percentage prevalence of 55% and 57.10% in urine and wound swab respectively for clinical samples, while Pseudomonas aeruginosa had a higher percentage prevalence of 62.50% in water for environmental sample. Overall, while Escherichia coli had a higher percentage prevalence of 55.55% in clinical samples, Pseudomonas aeruginosa recorded a higher percentage prevalence of 56.25% in environmental samples. Clinical isolates showed higher overall sensitivity to antibiotics compared to environmental isolates before plasmid curing. Post-curing, much of the resistance in clinical Escherichia coli was plasmid-mediated, while Pseudomonas aeruginosa exhibited predominantly chromosomal-mediated resistance. Environmental isolates demonstrated a more alarming resistance profile, especially in Escherichia coli, which was resistant to all tested antibiotics before curing, but with an improved sensitivity post-curing. Plasmid-mediated resistance was found to be the primary driver of multidrug resistance in environmental isolates and clinical Escherichia coli, while chromosomal-mediated resistance was more prominent in clinical Pseudomonas aeruginosa isolates. This study underscores the need for continuous monitoring of resistance patterns and targeted interventions to safeguard public health. Further research on genetic mechanisms of resistance and exploring alternative treatment options to enhance infection management strategies is recommended.



