Phenotypic and genotypic characterization of multi-drug resistance Pseudomonas aeruginosa isolated from urinary tract infections of non-catheterized and catheterized Chinese patients: A descriptive study over 3 years.

Abstract

Urinary tract infections (UTI) are commonest infections, especially in catheterized patients. It is responsible of mortality and morbidity among hospitalized patients. The objectives of the study were to demonstrate the virulence factors and their genes of multi-drug resistance Pseudomonas aeruginosa causing UTI. A total of 366 non-catheterized and 171 catheterized patients' (in whom the catheter was in > 48 hours duration) urine samples (one sample/patient) from both sexes were collected and processed. >105 colony forming unit was considered as Pseudomonas aeruginosa culture-positive. Antimicrobial susceptibility testing was done by the Kirby Bauer disc diffusion method (The Clinical and laboratory standards institute guidelines 2019). The virulence factors were detected by in vitro assay method and polymerase chain reaction was done to detect the resistance genes present in Pseudomonas aeruginosa. Biofilm production was detected by the microtiter plate method. Out of 537 urine samples a total of 280 (52%) were females and 257 (48%) were male patients. Out of 366 non-catheterized urine samples 42 (23.6%) grew Pseudomonas aeruginosa and out of 171 catheterized urine 23 (25.84%) grew Pseudomonas aeruginosa. All were multi-drug resistance strains. A total of 10 (23.80%), 42 (100%), 8 (19.05%), 24 (57.14%), and 36 (85.71%) produced the Metallo-β-lactamases, AmpC-β-lactamase, carbapenemase, strong biofilm, and twitching motility positive, respectively in non-catheterized urine samples. A total of 11, 34, 9, 28, and 37 were oxacillinases-23, multidrug efflux protein resistance, New Delhi metallo-ß-lactamase-1, Verona Integron-encoded MBL, and Pseudomonas specific enzyme gene detected in non-catheterized urine samples. A total of 8 (34.8%), 6 (26.01%), 4 (17.39%), 15 (65.2%), and 18 (78.26%) were produced Metallo-β-lactamases, carbapenemase, AmpC-β-lactamase, strong biofilm, and twitching motility positive, respectively in catheterized urine samples. A total of 6, 18, 4, 16, and 15 were oxacillinases 23, multidrug efflux protein resistance, New Delhi metallo-ß-lactamase-1, Verona Integron-encoded MBL, and Pseudomonas specific enzyme, respectively genes detected in catheterized urine samples. Biofilm formation and twitching motility showed correlation among culture-positive Pseudomonas aeruginosa strains from catheterized patients (Correlation coefficients = 6.2, 95% confidence interval: 5.4-7.2). A better hospital infection control practice and detailed investigation of the microevolution of Pseudomonas aeruginosa in UTI are needed.