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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
;
RIVAS JIMENEZ, LINA MARIA
;
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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Multisite Detection of Tn
<i>1549</i>
-Mediated
<i>vanB</i>
Vancomycin Resistance in Multidrug-Resistant Enterococcus faecalis ST6 in Texas and Florida
(2023)
Shelby R. Simar
;
Truc T. Tran
;
Kirsten B. Rydell
;
Diana Panesso
;
German A. Contreras
<jats:p> In the United States, <jats:italic>vanB</jats:italic> -mediated resistance in enterococci is rare. We characterized three sequence type (ST) 6, vancomycin-resistant <jats:named-content content-type="genus-species">Enterococcus faecalis</jats:named-content> isolates causing bacteremia in unique patients in spatiotemporally distinct settings. </jats:p>
7 1Scopus© Citations 3
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Antimicrobial Resistance Dynamics in Chilean Shigella sonnei Strains Within Two Decades: Role of Shigella Resistance Locus Pathogenicity Island and Class 1 and Class 2 Integrons
(2022)
Cecilia S. Toro
;
Juan Carlos Salazar
;
David A. Montero
;
Juan Antonio Ugalde
;
Janepsy Díaz
Shigellosis is an enteric infectious disease in which antibiotic treatment is effective, shortening the duration of symptoms and reducing the excretion of the pathogen into the environment. <jats:italic>Shigella</jats:italic> spp., the etiologic agent, are considered emerging pathogens with a high public health impact due to the increase and global spread of multidrug-resistant (MDR) strains. Since <jats:italic>Shigella</jats:italic> resistance phenotype varies worldwide, we present an overview of the resistance phenotypes and associated genetic determinants present in 349 Chilean <jats:italic>S. sonnei</jats:italic> strains isolated during the periods 1995–1997, 2002–2004, 2008–2009, and 2010–2013. We detected a great variability in antibiotic susceptibility patterns, finding 300 (86%) MDR strains. Mobile genetic elements (MGE), such as plasmids, integrons, and genomic islands, have been associated with the MDR phenotypes. The <jats:italic>Shigella</jats:italic> resistance locus pathogenicity island (SRL PAI), which encodes for ampicillin, streptomycin, chloramphenicol, and tetracycline resistance genes, was detected by PCR in 100% of the strains isolated in 2008–2009 but was less frequent in isolates from other periods. The presence or absence of SRL PAI was also differentiated by pulsed-field gel electrophoresis. An atypical class 1 integron which harbors the <jats:italic>bla</jats:italic><jats:sub>OXA–1</jats:sub><jats:italic>-aadA1-IS1</jats:italic> organization was detected as part of SRL PAI. The <jats:italic>dfrA14</jats:italic> gene conferring trimethoprim resistance was present in 98.8% of the 2008–2009 isolates, distinguishing them from the SRL-positive strains isolated before that. Thus, it seems an SRL-<jats:italic>dfrA14 S. sonnei</jats:italic> clone spread during the 2008–2009 period and declined thereafter. Besides these, SRL-negative strains harboring class 2 integrons with or without resistance to nalidixic acid were detected from 2011 onward, suggesting the circulation of another clone. Whole-genome sequencing of selected strains confirmed the results obtained by PCR and phenotypic analysis. It is highlighted that 70.8% of the MDR strains harbored one or more of the MGE evaluated, while 15.2% lacked both SRL PAI and integrons. These results underscore the temporal dynamics of antimicrobial resistance in <jats:italic>S. sonnei</jats:italic> strains circulating in Chile, mainly determined by the spread of MGE conferring MDR phenotypes. Since shigellosis is endemic in Chile, constant surveillance of antimicrobial resistance phenotypes and their genetic basis is a priority to contribute to public health policies.
Scopus© Citations 3 1
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Antimicrobial Susceptibility Testing for Enterococci
(2022)
Ayesha Khan
;
William R. Miller
;
Dierdre Axell-House
;
MUNITA SEPULVEDA, JOSE MANUEL
;
Cesar A. Arias
<jats:p>Enterococci are major, recalcitrant nosocomial pathogens with a wide repertoire of intrinsic and acquired resistance determinants and the potential of developing resistance to all clinically available antimicrobials. As such, multidrug-resistant enterococci are considered a serious public health threat.</jats:p>
1Scopus© Citations 57 1
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Clinical Outcome and Histological Findings After Induced Leakage of PMMA Loaded With Methotrexate and Cisplatin During Vertebroplasty: Experimental Model in Pigs
(2021)
Silva González, Alvaro
;
Rafael Llombart-Blanco
;
Gallegos Angulo, Marcela
;
Carlos Villas Tomé
;
Matías Alfonso Olmos-García
<jats:sec><jats:title>Study Design:</jats:title><jats:p> Animal experimental model. </jats:p></jats:sec><jats:sec><jats:title>Objective:</jats:title><jats:p> To study the clinical behavior and histological changes in the spinal cord, nerve roots and perivertebral muscles of the spine after induced leakage of polymethylmethacrylate (PMMA) loaded with antiblastic drugs during vertebroplasty in an animal model of pigs. </jats:p></jats:sec><jats:sec><jats:title>Methods:</jats:title><jats:p> We performed vertebroplasty on 25 pigs. The animals were divided into 3 groups: vertebroplasty with PMMA alone (control group), vertebroplasty with PMMA loaded with methotrexate (MTX) and vertebroplasty with PMMA loaded with cisplatin (CYS). At 2 vertebral levels, epidural and prevertebral, massive cement leaks were induced. Animals were evaluated daily. Two weeks later, the pigs were sacrificed, and the tissues that came in contact with the cement were analyzed. </jats:p></jats:sec><jats:sec><jats:title>Results:</jats:title><jats:p> The clinical results for each of the groups were reported. The control group had no clinical alterations. In the MTX group, 2 pigs died before 1 week due to pneumonitis. In the CYS group, 4 animals had motor impairment, and 3 of the 4 had paraplegia. The histological results were as follows: the control and MTX groups showed synovial metaplasia, inflammatory reaction, crystal deposits, and giant cell reaction in the dura mater and muscle and all the animals in the CYS group had spinal cord and muscular necrosis. </jats:p></jats:sec><jats:sec><jats:title>Conclusions:</jats:title><jats:p> Massive cement leak after vertebroplasty with PMMA loaded with cisplatin is extremely toxic to the spinal cord and muscles around the spine. Therefore, its use cannot be recommended for the treatment of vertebral metastases. Using PMMA loaded with methotrexate seems to be a safe procedure, but further research is needed. </jats:p></jats:sec>
6Scopus© Citations 4
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Novel Strategies for the Management of Vancomycin-Resistant Enterococcal Infections
(2019)
German A. Contreras
;
MUNITA SEPULVEDA, JOSE MANUEL
;
Cesar A. Arias
1Scopus© Citations 36

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