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    Isolation of Ciprofloxacin and Ceftazidime-Resistant Enterobacterales From Vegetables and River Water Is Strongly Associated With the Season and the Sample Type
    (2021)
    Constanza Díaz-Gavidia
    ;
    Carla Barría
    ;
    ;
    Patricia García
    ;
    Francisca P. Alvarez
    <jats:p>The dissemination of antibiotic-resistant bacteria (ARB) from water used for crop irrigation to vegetables is poorly studied. During a year, five farmer markets in a city in Central Chile were visited, and 478 vegetable samples (parsleys, corianders, celeries, lettuces, chards, and beets) were collected. Simultaneously, 32 water samples were collected from two rivers which are used to irrigate the vegetables produced in the area. Resistant Enterobacterales were isolated and identified. Colistin resistance gene <jats:italic>mcr-1</jats:italic> and extended spectrum β-lactamases (ESBL) were molecularly detected. The association of environmental factors was evaluated, with the outcomes being the presence of Enterobacterales resistant to four antibiotic families and the presence of multidrug resistance (MDR) phenotypes. Parsley, coriander, and celery showed the highest prevalence of resistant Enterobacterales (41.9% for ciprofloxacin and 18.5% for ceftazidime). A total of 155 isolates were obtained, including <jats:italic>Escherichia coli</jats:italic> (<jats:italic>n</jats:italic>=109), <jats:italic>Citrobacter</jats:italic> sp. (<jats:italic>n</jats:italic>=20), <jats:italic>Enterobacter cloacae</jats:italic> complex (<jats:italic>n</jats:italic>=8), <jats:italic>Klebsiella pneumoniae</jats:italic> (<jats:italic>n</jats:italic>=8), and <jats:italic>Klebsiella aerogenes</jats:italic> (<jats:italic>n</jats:italic>=1). Resistance to ampicillin (63.2%) and ciprofloxacin (74.2%) was most frequently found; 34.5% of the isolates showed resistance to third-generation cephalosporins, and the MDR phenotype represented 51.6% of the isolates. In two <jats:italic>E. coli</jats:italic> isolates (1.29%), the gene <jats:italic>mcr-1</jats:italic> was found and ESBL genes were found in 23/62 isolates (37%), with <jats:italic>bla</jats:italic><jats:sub>CTX-M</jats:sub> being the most frequently found in 20 isolates (32%). Resistant Enterobacterales isolated during the rainy season were less likely to be MDR as compared to the dry season. Understanding environmental associations represent the first step toward an improved understanding of the public health impact of ARB in vegetables and water.</jats:p>
      1Scopus© Citations 28
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    Scopus© Citations 8  4
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    Role of the multi-drug efflux systems on the baseline susceptibility to ceftazidime/avibactam and ceftolozane/tazobactam in clinical isolates of non-carbapenemase-producing carbapenem-resistant Pseudomonas aeruginosa
    (2022)
    María José Contreras-Gómez
    ;
    José R. W. Martinez
    ;
    ;
    Juan A. Ugalde
    ;
    <jats:p>Carbapenem-resistant <jats:italic>Pseudomonas aeruginosa</jats:italic> (CRPA) is one of the pathogens that urgently needs new drugs and new alternatives for its control. The primary strategy to combat this bacterium is combining treatments of beta-lactam with a beta-lactamase inhibitor. The most used combinations against <jats:italic>P. aeruginosa</jats:italic> are ceftazidime/avibactam (CZA) and ceftolozane/tazobactam (C/T). Although mechanisms leading to CZA and C/T resistance have already been described, among which are the resistance-nodulation-division (RND) efflux pumps, the role that these extrusion systems may play in CZA, and C/T baseline susceptibility of clinical isolates remains unknown. For this purpose, 161 isolates of non-carbapenemase-producing (Non-CP) CRPA were selected, and susceptibility tests to CZA and C/T were performed in the presence and absence of the RND efflux pumps inhibitor, Phenylalanine-arginine β-naphthylamide (PAβN). In the absence of PAβN, C/T showed markedly higher activity against Non-CP-CRPA isolates than observed for CZA. These results were even more evident in isolates classified as extremely-drug resistant (XDR) or with difficult-to-treat resistance (DTR), where CZA decreased its activity up to 55.2% and 20.0%, respectively, whereas C/T did it up to 82.8% (XDR), and 73.3% (DTR). The presence of PAβN showed an increase in both CZA (37.6%) and C/T (44.6%) activity, and 25.5% of Non-CP-CRPA isolates increased their susceptibility to these two combined antibiotics. However, statistical analysis showed that only the C/T susceptibility of Non-CP-CRPA isolates was significantly increased. Although the contribution of RND activity to CZA and C/T baseline susceptibility was generally low (two-fold decrease of minimal inhibitory concentrations [MIC]), a more evident contribution was observed in a non-minor proportion of the Non-CP-CRPA isolates affected by PAβN [CZA: 25.4% (15/59); C/T: 30% (21/70)]. These isolates presented significantly higher MIC values for C/T. Therefore, we conclude that RND efflux pumps are participating in the phenomenon of baseline susceptibility to CZA and, even more, to C/T. However, the genomic diversity of clinical isolates is so great that deeper analyzes are necessary to determine which elements are directly involved in this phenomenon.</jats:p>
    Scopus© Citations 2  1
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    Real-World Performance of Susceptibility Testing for Ceftolozane/Tazobactam against Non-Carbapenemase-Producing Carbapenem-Resistant Pseudomonas aeruginosa
    (2022) ;
    Manuel Alcalde-Rico
    ;
    José R. W. Martínez
    ;
    María Victoria Moreno
    ;
    Pamela Rojas
    <jats:p> Ceftolozane/tazbactam (C/T) is a potent anti-pseudomonal agent that has clinical utility against infections caused by non-carbapenemase, producing-carbapenem-resistant <jats:named-content content-type="genus-species">Pseudomonas aeruginosa</jats:named-content> (non-CP-CR-PA). Accurate, precise, and reliable antimicrobial susceptibility testing (AST) is crucial to guide clinical decisions. </jats:p>
      19Scopus© Citations 2
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    Preschool Girl With Vaginal Bleeding Due to Pinworm Endometritis
    (2020)
    Andrea von Höveling
    ;
    Lilian Carrasco
    ;
    ;
    Gioconda Martinez
    ;
    Cristina Riquelme
      3Scopus© Citations 6
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    Clinical Predictive Model of Multidrug Resistance in Neutropenic Cancer Patients with Bloodstream Infection Due to Pseudomonas aeruginosa
    (2020)
    C. Gudiol
    ;
    A. Albasanz-Puig
    ;
    J. Laporte-Amargós
    ;
    N. Pallarès
    ;
    A. Mussetti
    <jats:p> We aimed to assess the rate and predictive factors of bloodstream infection (BSI) due to multidrug-resistant (MDR) <jats:named-content content-type="genus-species">Pseudomonas aeruginosa</jats:named-content> in neutropenic cancer patients. We performed a multicenter, retrospective cohort study including oncohematological neutropenic patients with BSI due to <jats:named-content content-type="genus-species">P. aeruginosa</jats:named-content> conducted across 34 centers in 12 countries from January 2006 to May 2018. A mixed logistic regression model was used to estimate a model to predict the multidrug resistance of the causative pathogens. </jats:p>
      4  1Scopus© Citations 60