multiple-locus variable-number tandem repeat analysis genotyping of biofilm-producing pseudomonas aeruginosa clinical isolates

Pseudomonas aeruginosasignificantly contributes to hospital-acquired infections. objectives: this study aimed to investigate the genetic diversity of p. aeruginosastrains using multiple-locus variable-number tandem repeat analysis (mlva) and to explore the relationship between biofilm production and antibiotic resistance. methods: in this cross-sectional study, 79 p. aeruginosaisolates were collected. antibiotic sensitivity was tested using the kirby-bauer method, and biofilm production capability was assessed through the microtiter plate method. genetic diversity was evaluated by mlva, analyzing eight variable-number tandem repeat (vntr) loci: ms-213, ms-214, ms-207, ms-217, ms-222, ms-209, ms-77, and ms-172. phylogenetic relationships were delineated using phyloviz 2.0 software. results: the patient cohort comprised 51.9% males, with the majority of samples (35.4%) obtained from urine. ceftazidime (caz 30µg) showed the highest resistance rate at 77.2%. notably, 92.4% of isolates were capable of forming biofilms, categorized as 22.7% weak, 28.7% moderate, and 46.5% strong. phylogenetic analysis demonstrated variability across one or more vntr loci. simpson’s index (0.906) and shannon-weiner diversity indices (h: 3.466, j: 0.910, hmax: 3.807, hmin: 1.242) identified ms77 as the most informative marker for genetic diversity among the isolates. conclusions: the study highlights an alarming trend in antibiotic resistance, underscoring the necessity of regular monitoring. the findings confirm that mlva is a straightforward, rapid genotyping method suitable for assessing the genetic diversity of p. aeruginosa.