Isolation of Pseudomonas aeruginosa from Persistent Bacterial Coinfection of a COVID-19 Patients with Molecular Detection of Antibiotics Resistance Genes.

Pseudomonas aeruginosa (P. aeruginosa) have a considerable risk to public health in the world, due to its high ability to develop resistance to different classes of antibiotics. It has been discovered as a prevalent coinfection pathogen that causes sickness exacerbation in COVID-19 patients. This study aimed to determine the prevalence of P. aeruginosa from COVID-19 patients in Al Diwaniyah province, Iraq and to identify its genetic resistance pattern. 70 clinical samples were obtained from severe cases of patients (RT-PCR positive for SARS-COV-2 on a nasopharyngeal swab) who attended Al Diwaniyah Academic Hospital. 50 P. aeruginosa bacterial isolates were detected via microscopic examination, routine cultured and biochemical testing, then validated by the VITEK-2 compact system. VITEK reported 30 positive results, which later confirmed through molecular detection using 16s RNA specific for detection and a phylogenetic tree.20 isolates had positive PCR findings and 5 isolates submitted to GenBank with accession numbers OL314557.1, OL314556.1, OL314555.1, OL314554.1, OL314553.1.For antibiotic resistance genes, the number of the isolates containing blaOXA-1 and blaCTX-M 18 (90 percent) and 16 (80 percent) respectively. To study its adaptation in a SARS-CoV-2 infected environment, genomic sequencing investigations were undertaken with phenotypic validation. In conclusion, we demonstrate that multidrug resistant P. aeruginosa play an important role in in vivo colonization in COVID-19 patients and could be one of the causes of death of these patients which indicates the great challenge to clinicians in the facing of this serious disease.

Characterization of IncI1/ST71 and IncF18:A-:B1 multidrug-resistance plasmids from an avian Escherichia coli isolate.

To characterize IncI1 and IncF18:A-:B1 multidrug-resistance plasmids from an avian Escherichia coli isolate, antibiotic susceptibility testing, conjugation assays, transformation assays, S1-PFGE, and WGS analysis were performed. The 119,457-bp plasmid pEC014-1 with a multidrug-resistance region (MRR) containing four different segments interspersed with six IS26 elements, belonged to incompatibility group I1 and sequence type 71. The 154,516-bp plasmid pEC014-2 with two replicons, typed as FII-18 and FIB-1, carried 14 resistance determinants including blaTEM-1b, blaOXA-1, oqxAB, dfrA17, aac(6')-Ib-cr, sul1, sul2, tet(A), floR, catB3, hph(aph(4)-Ia), aacC4(aac(3)-IV), aadA5, arr-3, and a merEDACPTR loci in MRR, and additionally encoded three virulence loci: iroNEDCB, sitABCD, and iucABCD-iutA. Plasmid stability assays showed that pEC014-1 and pEC014-2 were stable in recipient E. coli C600 for at least 15 days of passage. Competition assays were carried out to evaluate the fitness impact of pEC014-2 carriage in vitro, revealing a decrease in host fitness. Growth kinetics showed that the growth rate for pEC014-1 or/and pEC014-2 bearing cells was significantly slower than that of the E. coli C600 host strain in the exponential stage (p < 0.01), with only cells carrying pEC014-1 sustaining rapid growth after 6 h of exponential growth. Our findings highlight the mosaic structures of epidemic plasmid IncI1/ST71 and F18:A-:B1 lineages and contribute to a better understanding of the evolution and dissemination of these multidrug resistance and virulence plasmids.

Antibiogram and beta-lactamase genes among cefotaxime resistant E. coli from wastewater treatment plant.

BACKGROUND: The World Health Organization (WHO) recently classified Enterobacteriaceae resistance to third-generation cephalosporin into the group of pathogens with critical criteria for future research. METHODS: A study to assess the antibiogram and beta-lactamase genes among the cefotaxime resistant E. coli (CREc) from a South African wastewater treatment plant (WWTP) was conducted using standard phenotypic and molecular biology characterization methods. RESULTS: Approximate total E. coli (TEc) concentration (log10 CFU/mL) ranged between 5.7 and 6.8 among which cefotaxime resistant E. coli were between 1.8 and 4.8 (log10 CFU/mL) for cefotaxime antibiotic concentration of 4 and 8 mg/L in the influent samples. Effluent samples, heavily influenced by the chlorination had only 0.3 log10 CFU/mL of TEc. Fifty-one cefotaxime resistant isolates were selected out of an overall of 75 isolates, and subjected to a new round of testing, with a follow up of 36 and 48 isolates for both colistin and gentamicin, respectively as guided by initial results. Selected CREc exhibited resistance to amoxicillin-clavulanic acid (35.3%; n = 51), colistin sulphate (76.5%; n = 36), ciprofloxacin (47.1%; n = 51), gentamicin (87.5%; n = 48) and intermediate-resistance to meropenem (11.8%; n = 51). Extended spectrum-beta-lactamase genes detected, viz.: blaCTX-M (52.6%; n = 38) and blaTEM (84.2%; n = 38) and concurrent blaCTX-M + blaTEM (36.8%; n = 38), but no blaSHV was detected. Carbapenem resistance genes, blaKPC-2 (15.8%; n = 38), blaOXA-1 (57.9%; n = 38), blaNDM-1 (15.8%; n = 38) were also detected. Approximately, 10.5 - 36.8% (n = 38) co-occurrence of two or more beta-lactamase genes was detected in some isolates. Out of the selected number (n = 30), 7(23.3%) were enterotoxigenic E. coli (ETEC), 14 (46.7%) were Enteroaggregative E. coli (EAEC), but no enteropathogenic E. coli (EPEC) was detected. CONCLUSION: Resistance to cefotaxime and the presence of a wide range of beta-lactamase genes exposed the potential risks associated with these pathogens via occupational and domestic exposure during the reuse of treated wastewater.

Complete sequence of pBM413, a novel multidrug resistance megaplasmid carrying qnrVC6 and blaIMP-45 from pseudomonas aeruginosa.

This study aimed to characterise a novel multidrug resistance megaplasmid carrying qnrVC6 and blaIMP-45 from Pseudomonas aeruginosa strain Guangzhou-Pae617 isolated from a patient hospitalised in Guangzhou, China, in 2012. The plasmid pBM413 has a length of 423 017 bp and an average G + C content of 56.41%. A qnrVC6 gene flanked by two copies of insertion sequence (IS) elements ISCR1, a multiresistance class 1 integron In786 containing aacA4-blaIMP-45-blaOXA-1-catB3 cassettes, an armA gene, and an aphA7 gene flanked by two copies of IS26 were identified. To our knowledge, this is the first identification of a qnrVC6 gene in P. aeruginosa.

[Antibiotic resistance and virulence factors in clinical Salmonella enterica isolates]. / Resistencia a antibióticos y factores de virulencia en aislados clínicos de Salmonella enterica.

INTRODUCTION: The increase of Salmonella enterica isolates multi-resistant to different antibiotics, including ß-lactams and fluoroquinolones, is a problem of clinical importance. The dissemination of Salmonella Typhimurium resistant to ampicillin (AMP)-chloramphenicol (CHL)-streptomycin (STR)-sulphonamides and (SUL)-tetracycline (TET), that harbour the Salmonella Genomic Island type 1 (SGI1), and the acquisition of transferable genetic material have favoured the multi-resistance in this genus. METHODS: A total of 114 clinical S.enterica isolates were studied (period 2009-2010). The susceptibility to 20 antibiotics was determined by disc diffusion and microdilution. The antimicrobial resistance mechanisms and the integrons were analysed by PCR, and sequencing in the AMP(R) isolates. In all the blaPSE-1-positive isolates, the clonal relationship was determined by PFGE, as well as the presence of SGI1 and 29 virulence genes by PCR. RESULTS: Eighteen different serotypes were found among the 114 isolates studied, Typhimurium (61%) and Enteritidis (16%) being the most prevalent. High percentages of resistance to SUL (68%), TET (58%), AMP (55%) and STR (46%) were observed. The great majority (92%) of 63 AMP(R) isolates were multi-resistant, with the AMP-STR-TET-SUL phenotype (19 isolates) being the most frequent one and associated with the blaTEM-1b+strA-strB+tet(B)+sul2 genotype. Class 1 integrons (7 different structures) were observed in 48% AMP(R) isolates, highlighting the blaOXA-1+aadA1 structure (8 isolates), one empty integron and non-classical integrons (5 isolates). The blaPSE-1 gene was detected inside the classical SGI1 structure in 13 clonally-related isolates that showed the same virulence profile. CONCLUSIONS: The high percentage of multi-resistant S.enterica isolates, especially associated to S.Typhimurium, to the AMP, STR, TET and SUL phenotype, and to the blaTEM-1b+strA-strB+tet(B)+sul2 genotype, shows an important risk of possible failures in the treatment of serious infections caused by this serotype.