1
|
An Improved Extended-Spectrum-β-Lactamase Detection Test Utilizing Aztreonam plus Clavulanate. J Clin Microbiol 2018; 56:JCM.01309-17. [DOI: 10.1128/jcm.01309-17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 10/04/2017] [Indexed: 11/20/2022] Open
Abstract
ABSTRACT
Clinical laboratories test for extended-spectrum β-lactamases (ESBLs) for epidemiological and infection control purposes and also for the potential of cephalosporins to cause therapeutic failures. Testing can be problematic, because the CLSI does not recommend the testing of all producers of ESBLs and also falsely negative results may occur with isolates that coproduce AmpC. Boronic acid-supplemented tests can enhance ESBL detection in AmpC producers. Because aztreonam inhibits AmpCs, a study was designed to compare ESBL detection by the CLSI disk test (CLSI), a boronic acid-supplemented CLSI disk test (CLSI plus BA), and an aztreonam plus clavulanate disk test (ATM plus CA). The study tested 100 well-characterized
Enterobacteriaceae
,
Acinetobacter baumannii
, and
Pseudomonas aeruginosa
isolates. Seventy produced TEM, SHV, or CTX-M ESBLs, with 15 coproducing an AmpC and 11 coproducing a metallo-β-lactamase. Thirty ESBL-negative isolates were also tested. Tests were inoculated by CLSI methodology and interpreted as positive if an inhibitor caused a zone diameter increase of ≥5 mm. The percentages of ESBL producers detected were as follows: ATM plus CA, 95.7%; CLSI plus BA, 88.6%; and CLSI, 78.6%. When AmpC was coproduced, the sensitivities of the tests were as follows: ATM plus CA, 100%; CLSI plus BA, 93.3%; and CLSI, 60%. ATM plus CA also detected an ESBL in 90.1% of isolates that coproduced a metallo-β-lactamase. Falsely positive tests occurred only with the CLSI and CLSI plus BA tests. Overall, the ATM plus CA test detected ESBLs more accurately than the CLSI and CLSI plus BA tests, especially with isolates coproducing an AmpC or metallo-β-lactamase.
Collapse
|
2
|
Conte D, Palmeiro JK, da Silva Nogueira K, de Lima TMR, Cardoso MA, Pontarolo R, Degaut Pontes FL, Dalla-Costa LM. Characterization of CTX-M enzymes, quinolone resistance determinants, and antimicrobial residues from hospital sewage, wastewater treatment plant, and river water. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2017; 136:62-69. [PMID: 27816836 DOI: 10.1016/j.ecoenv.2016.10.031] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 10/21/2016] [Accepted: 10/25/2016] [Indexed: 05/09/2023]
Abstract
Multidrug-resistant (MDR) bacteria are widespread in hospitals and have been increasingly isolated from aquatic environments. The aim of the present study was to characterize extended-spectrum β-lactamase (ESBL) and quinolone-resistant Enterobacteriaceae from a hospital effluent, sanitary effluent, inflow sewage, aeration tank, and outflow sewage within a wastewater treatment plant (WWTP), as well as river water upstream and downstream (URW and DRW, respectively), of the point where the WWTP treated effluent was discharged. β-lactamase (bla) genes, plasmid-mediated quinolone resistance (PMQR), and quinolone resistance-determining regions (QRDRs) were assessed by amplification and sequencing in 55 ESBL-positive and/or quinolone-resistant isolates. Ciprofloxacin residue was evaluated by high performance liquid chromatography. ESBL-producing isolates were identified in both raw (n=29) and treated (n=26) water; they included Escherichia coli (32), Klebsiella pneumoniae (22) and Klebsiella oxytoca (1). Resistance to both cephalosporins and quinolone was observed in 34.4% of E. coli and 27.3% of K. pneumoniae. Resistance to carbapenems was found in 5.4% of K. pneumoniae and in K. oxytoca. Results indicate the presence of blaCTX-M (51/55, 92.7%) and blaSHV (8/55, 14.5%) ESBLs, and blaGES (2/55, 3.6%) carbapenemase-encoding resistance determinants. Genes conferring quinolone resistance were detected at all sites, except in the inflow sewage and aeration tanks. Quinolone resistance was primarily attributed to amino acid substitutions in the QRDR of GyrA (47%) or to the presence of PMQR (aac-(6')-Ib-cr, oqxAB, qnrS, and/or qnrB; 52.9%) determinants. Ciprofloxacin residue was absent only from URW. Our results have shown strains carrying ESBL genes, PMQR determinants, and mutations in the gyrA QRDR genes mainly in hospital effluent, URW, and DRW samples. Antimicrobial use, and the inefficient removal of MDR bacteria and antibiotic residue during sewage treatment, may contribute to the emergence and spreading of resistance in the environment, making this a natural reservoir.
Collapse
Affiliation(s)
- Danieli Conte
- Faculdades e Instituto de Pesquisa Pelé Pequeno Príncipe (FPP/IPPPP), Curitiba, Paraná, Brazil.
| | - Jussara Kasuko Palmeiro
- Faculdades e Instituto de Pesquisa Pelé Pequeno Príncipe (FPP/IPPPP), Curitiba, Paraná, Brazil; Hospital de Clínicas, Universidade Federal do Paraná (HC-UFPR), Curitiba, Paraná, Brazil.
| | - Keite da Silva Nogueira
- Departamento de Patologia Básica, Setor de Ciências Biológicas, Universidade Federal do Paraná, Curitiba, Paraná, Brazil.
| | | | - Marco André Cardoso
- Faculdades e Instituto de Pesquisa Pelé Pequeno Príncipe (FPP/IPPPP), Curitiba, Paraná, Brazil; Pharmacy Department, Health Sciences Sector, Universidade Federal do Paraná (UFPR), Curitiba, Paraná, Brazil.
| | - Roberto Pontarolo
- Pharmacy Department, Health Sciences Sector, Universidade Federal do Paraná (UFPR), Curitiba, Paraná, Brazil.
| | - Flávia Lada Degaut Pontes
- Pharmacy Department, Health Sciences Sector, Universidade Federal do Paraná (UFPR), Curitiba, Paraná, Brazil.
| | - Libera Maria Dalla-Costa
- Faculdades e Instituto de Pesquisa Pelé Pequeno Príncipe (FPP/IPPPP), Curitiba, Paraná, Brazil; Hospital de Clínicas, Universidade Federal do Paraná (HC-UFPR), Curitiba, Paraná, Brazil.
| |
Collapse
|
3
|
Multidrug resistance and ESBL-producing Salmonella spp. isolated from broiler processing plants. Braz J Microbiol 2016; 47:191-5. [PMID: 26887244 PMCID: PMC4822755 DOI: 10.1016/j.bjm.2015.11.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 07/24/2015] [Indexed: 02/07/2023] Open
Abstract
The aim of this study was to investigate the occurrence of multidrug-resistant, extended spectrum beta-lactamase (ESBL) producing Salmonella spp. isolated from conveyor belts of broiler cutting rooms in Brazilian broiler processing plants. Ninety-eight strains of Salmonella spp. were analyzed. Multidrug resistance was determined by the disk diffusion test and the susceptibility of the isolated bacteria was evaluated against 18 antimicrobials from seven different classes. The double disk diffusion test was used to evaluate ESBL production. Of the 98 strains tested, 84 were multidrug resistant. The highest rates of resistance were against nalidixic acid (95%), tetracycline (91%), and the beta-lactams: ampicillin and cefachlor (45%), followed by streptomycin and gentamicin with 19% and 15% of strain resistance, respectively. By contrast, 97% of the strains were sensitive to chloramphenicol. 45% of the strains were positive for the presence of ESBL activity. In this study, high rates of multidrug resistance and ESBL production were observed in Salmonella spp.
Collapse
|
5
|
Orsini J, Mainardi C, Muzylo E, Karki N, Cohen N, Sakoulas G. Microbiological profile of organisms causing bloodstream infection in critically ill patients. J Clin Med Res 2012; 4:371-7. [PMID: 23226169 PMCID: PMC3513418 DOI: 10.4021/jocmr1099w] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/23/2012] [Indexed: 01/08/2023] Open
Abstract
Background Bloodstream infection (BSI) is the most frequent infection in critically ill patients. As BSI’s among patients in intensive care units (ICU’s) are usually secondary to intravascular catheters, they can be caused by both Gram-positive and Gram-negative microorganisms as well as fungi. Infection with multidrug-resistant (MDR) organisms is becoming more common, making the choice of empirical antimicrobial therapy challenging. The objective of this study is to evaluate the spectrum of microorganisms causing BSI’s in a Medical-Surgical Intensive Care Unit (MSICU) and their antimicrobial resistance patterns. Methods A prospective observational study among all adult patients with clinical signs of sepsis was conducted in a MSICU of an inner-city hospital in New York City between May 1, 2010 and May 30, 2011. Results A total of 722 adult patients with clinical signs of systemic inflammatory response syndrome (SIRS) and/or sepsis were admitted to the MSICU between May 1, 2010 and May 30, 2011. From those patients, 91 (12.6%) had one or more positive blood culture. A 122 isolates were identified: 72 (59%) were Gram-positive bacteria, 38 (31.1%) were Gram-negative organisms, and 12 (9.8%) were fungi. Thirteen (34.2%) Gram-negative organisms and 14 (19.4%) Gram-positive bacteria were classified as MDR. Conclusions Antimicrobial resistance, particularly among Gram-negative organisms, continues to increase at a rapid rate, especially in the ICU’s. Coordinated infection control interventions and antimicrobial stewardship policies are warranted in order to slow the emergence of resistance.
Collapse
Affiliation(s)
- Jose Orsini
- Department of Medicine, New York University School of Medicine at Woodhull Medical and Mental Health Center, USA
| | | | | | | | | | | |
Collapse
|