Antibiotic resistance, virulence factors and genotyping of Pseudomonas aeruginosa in public hospitals of northeastern Mexico

Abstract

Introduction: Pseudomonas aeruginosa is the second most prevalent opportunistic pathogen causing nosocomial infections in Mexico. This study evaluated antibiotic resistance, production of virulence factors and clonal diversity of P. aeruginosa strains isolated from patients undergoing nosocomial infections in public hospitals of northeastern Mexico.
 Methodology: Ninety-two P. aeruginosa isolates from urine culture, Foley catheter, ear, wounds, respiratory tract secretions, scalp, blood culture, bronchoalveolar lavage, expectoration and cerebrospinal fluid causing nosocomial infections were analyzed. The isolates were identified by MALDI-TOF and antibiotic resistance profiles obtained by MicroScan®. The production of virulence factors was analyzed with spectrophotometric techniques and isolates genotyped by ERIC-PCR.
 Results: Out of the 92 isolates, 26 (28.2%) were found to be multidrug resistant (MDR); 21 (22.7%) were classified as extremely drug resistant (XDR). Highest resistance rate was found for gatifloxacin (42%) while ciprofloxacin accounted for the antibiotic with the lowest resistance rate (2%). Bronchoalveolar lavage isolates produced the highest amounts of virulence factors: biofilm (44.4% ± 2.7%), elastase (58.5% ± 4.3%), alkaline protease (60.1% ± 5.0%); except for pyocyanin production. The ERIC-PCR assay showed 83 genetic patterns (90% clonal diversity) and 13 isolates had 100% genetic similarity, forming 4 real clones, 3 of these clones were obtained from different anatomical site and/or hospital.
 Conclusions: Antibiotic resistance and virulence factors production was heterogeneous among samples analyzed. Genotyping of P. aeruginosa strains showed high genetic diversity in the studied isolates.

Pseudomonas aeruginosa Pneumonia: Evolution of Antimicrobial Resistance and Implications for Therapy

“…106 PA can amplify or reduce effects such as modulation of the host immune response and pathogen-induced injury to the host. 96 97 PA can adapt in chronic conditions (e.g., CF), by reducing injury to the host while mitigating host-immune responses to the bacteria, favoring bacterial persistence. 96 In some cases, emergence of AMR can be associated with increased virulence.…”

“…PA has a large genome and has the ability, both from intrinsic and mutant genotypes, to produce diverse factors that influence virulence, motility (e.g., flagellin, TipP), metabolism (e.g., iron uptake), efflux pumps, and AMR. 96 PA expresses virulence factors (e.g., elastase, alkaline protease, pyocyanin) 97 that break extracellular laminin, degrade innate immune system proteins (e.g., surfactant A and D), and form biofilms, which inhibit penetration of antibiotics across the cell membrane. 92,97,98 PA is genetically flexible and survives in diverse environments.…”

“…255 In another report of clinical isolates of PA from Mexican hospitals in 2019, twenty-seven of 92 were MDR (28.2%); 21 were XDR (22.7%). 97 A few "high-risk" clones account for a significant proportion of MDR/XDR isolates globally. 144,230,[236][237][238][239] ST235 has the widest distribution, present in five continents.…”

“…255 In another report of clinical isolates of PA from Mexican hospitals in 2019, twenty-seven of 92 were MDR (28.2%); 21 were XDR (22.7%). 97…”

Cloning and Characterization of phzR Gene from Pseudomonas aeruginosa

“…In order to enhance metabolite production, the expression vector carrying the target gene is transformed into the wild strain. The former studies found that Pseudomonas aeruginosa was resistant to many antibiotics [19][20][21][22]. Therefore, determination of sensitive antibiotics for P. aeruginosa 2016NX1 was necessary.…”