RESUMO
OBJECTIVES: We aimed to evaluate the impact of the 10th version of European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints table, where most antipseudomonal drugs but meropenem are now categorised as "Susceptible, increased exposure" and labelled I, on meropenem prescription for Pseudomonas aeruginosa infections. METHODS: In this retrospective single-centre observational study, we analysed antimicrobial therapies prescribed after susceptibility testing in all consecutive adult patients treated for P. aeruginosa infections between 01.08.2019 and 30.07.2020 in Lausanne University Hospital, Switzerland. We collected epidemiological, microbiological, clinical data, antimicrobial therapy, and infectious diseases specialists (IDs) consultations' data. The primary outcome was the prescription of meropenem to treat P. aeruginosa infections after release of susceptibility testing results. Secondary outcomes were: the use of increased dosage for non-meropenem anti-pseudomonal drugs, and IDs' consultations rates after susceptibility testing was made available. RESULTS: Among the 264 patients included, 40 (15.2%) received meropenem, 3.4% (5/148) before EUCAST update versus 30.2% (35/116) after (p < 0.001). Supervision and counselling from IDs and the use of increased dosages of non-carbapenem antibiotics also increased respectively (40.5% (60/148) vs 62.9% (73/116), P < 0.001); (55.5% (76/148) vs 88.9% (72/116), P < 0.001). Factors associated with these increments could not be adequately modelled. CONCLUSIONS: The change to 2020 EUCAST criteria might be associated with increased odds of meropenem prescription for the treatment of P. aeruginosa infections stressing the need of prescribers' education and the importance of antibiotic stewardship interventions.
Assuntos
Infecções por Pseudomonas , Antibacterianos/uso terapêutico , Hospitais , Humanos , Meropeném/uso terapêutico , Testes de Sensibilidade Microbiana , Prescrições , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa , Estudos RetrospectivosRESUMO
In our tertiary care center, the reported susceptibility of E. coli blood isolates to amoxicillin/clavulanic acid exceeded 90% in 2005 and showed a progressive decrease to 50% by 2017. In this study, we investigate whether there is a real increase in resistant E. coli strains or if this apparent decline in reported susceptibility might be attributed to the substitution of CLSI by EUCAST guidelines in 2014. We randomly selected 237 E. coli blood isolates (stored at - 80 °C) from 1985 to 2018 and reassessed their MIC values, applying both the CLSI (fixed ratio of clavulanic acid) and EUCAST guidelines (fixed concentration of clavulanic acid). In parallel, the susceptibility of these isolates was retested by disk diffusion, according to the EUCAST guidelines. Whole genome sequencing was successfully performed on 233 of the 237 isolates. In only 130 of the 237 isolates (55.0%), testing according to the EUCAST and CLSI criteria delivered identical MIC values for amoxicillin/clavulanic acid. In 64 of the 237 isolates (27.0%), the MIC values diverged one dilution; in 38 (16.0%), two dilutions; and in five (2.1%), three dilutions. From these 107 discrepant results, testing according to EUCAST methodology revealed more resistant profiles in 93 E. coli strains (94.1%). Also, phenotypical susceptibility testing according to EUCAST guidelines tends to correlate better with the presence of beta-lactamase genes compared to CLSI testing procedure. This study highlights the low agreement between EUCAST and CLSI methodologies when performing MIC testing of amoxicillin/clavulanic acid. More strains are categorized as resistant when EUCAST guidelines are applied. The low agreement between EUCAST and CLSI was confirmed by WGS, since most of EUCAST resistant/CLSI sensitive isolates harbored beta-lactamase genes.
Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Antibacterianos/uso terapêutico , Infecções por Escherichia coli/microbiologia , Escherichia coli/efeitos dos fármacos , Combinação Amoxicilina e Clavulanato de Potássio/normas , Antibacterianos/normas , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/fisiologia , Infecções por Escherichia coli/tratamento farmacológico , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Europa (Continente) , Humanos , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , beta-Lactamases/metabolismoRESUMO
The requirement for antifungal susceptibility testing is increasing given the availability of new drugs, increasing populations of individuals at risk for fungal infection, and emerging multiresistant fungi. Rapid and accurate fungal identification remains at the forefront of laboratory efforts to guide empiric therapy. Antifungal susceptibility testing methods have greatly improved, but are subject to variation in results between methods. Careful standardization, validation, and extensive training of users is essential to ensure susceptibility results are clinically useful and interpreted appropriately. Interpretive criteria for many drugs and species are still lacking, but this will continue to evolve.
Assuntos
Antifúngicos/uso terapêutico , Farmacorresistência Fúngica , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Antifúngicos/farmacologia , Determinação de Ponto Final , Fungos/classificação , Fungos/isolamento & purificação , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Posaconazole is more active than fluconazole against Candida albicansin vitro and is approved for the treatment of oropharyngeal candidiasis but not for that of invasive candidiasis (IC). Here, we explored the efficacy of posaconazole against C. albicans in an in vitro pharmacokinetic/pharmacodynamic (PK/PD) model of IC and determined the probability of pharmacodynamic target attainment for the oral solution and intravenous (i.v.)/tablet formulations. Three clinical C. albicans isolates (posaconazole MICs, 0.008 to 0.25 mg/liter) were studied in the in vitro PK/PD dilution model simulating steady-state posaconazole PK. The in vitro exposure-effect relationship, area under the 24-h free drug concentration curve (fAUC0-24)/MIC, was described and compared with in vivo outcome in animals with IC. PK/PD susceptibility breakpoints and trough levels required for optimal treatment were determined for EUCAST and CLSI 24-h/48-h (CLSI24h/CLSI48h) methods using the fAUC0-24/MIC associated with half-maximal activity (EI50) and Monte Carlo simulation analysis for oral solution (400 mg every 12 hours [q12h]) and i.v./tablet formulations (300 mg q24h). The in vitro mean (95% confidence interval [CI]) EI50 was 330 (183 to 597) fAUC0-24/MIC for CLSI24h and 169 (92 to 310) for EUCAST/CLSI48h methods, which are close to the near-stasis in vivo effect. The probability of target attainment for EI50 was estimated; for the wild-type isolates (MIC ≤ 0.06 mg/liter), it was low for the oral solution and higher than 95% for the i.v./tablet formulations for the EUCAST/CLSI48h methods but not for the CLSI 24-h method. Non-wild-type isolates with EUCAST/CLSI48h MICs of 0.125 and 0.25 mg/liter would require trough levels of >1.2 and >2.4 mg/liter, respectively. Posaconazole i.v./tablet formulations may have a role in the therapy of invasive infections by wild-type C. albicans isolates, provided that a steady state is reached quickly. A PK/PD susceptibility breakpoint at the epidemiological cutoff (ECV/ECOFF) of 0.06 mg/liter was determined.
Assuntos
Antifúngicos , Candida albicans , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Testes de Sensibilidade Microbiana , Triazóis/farmacologiaAssuntos
Antibacterianos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Tigeciclina , Transplantados , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Tigeciclina/uso terapêuticoRESUMO
Antifungal susceptibility profiles of rare Saccharomycotina yeasts remain missing, even though an increase in prevalence of such rare Candida species was reported in candidemia. Majority of these rare yeast species carry intrinsic resistances against at least one antifungal compound. Some species are known to be cross-resistant (against multiple drugs of the same drug class) or even multi-drug resistant (against multiple drugs of different drug classes). We performed antifungal susceptibility testing (AFST) according to EUCAST broth microdilution for 14 rare species (Clavispora lusitaniae, Candida intermedia, Candida auris, Diutina rugosa, Wickerhamiella pararugosa, Yarrowia lipolytica, Pichia norvegensis, Candida nivariensis, Kluyveromyces marxianus, Wickerhamomyces anomalus, Candida palmioleophila, Meyerozyma guilliermondii, Meyerozyma caribbica, and Debaryomyces hansenii) known to cause candidemia. In total, 234 isolates were tested for amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, anidulafungin, micafungin, and caspofungin. Amphothericin B had the broadest efficiency against the 14 tested rare yeast species, while high minimum inhibitory concentrations (MICs) against azole drugs and echinocandins were common. Voriconazole was the most efficient azole drug. Multidrug resistance was observed for the species C. auris and K. marxianus. Multidrug resistant individual isolates were found for Y. lipolytica and M. caribbica. In conclusion, the observed high MIC values of the rare Saccharomycotina species tested limit antifungal treatment options, complicating the management of such infections.
Assuntos
Antifúngicos/uso terapêutico , Candidemia/tratamento farmacológico , Farmacorresistência Fúngica , Fluconazol/uso terapêutico , Testes de Sensibilidade Microbiana , Saccharomyces/efeitos dos fármacos , Saccharomyces/isolamento & purificação , Voriconazol/uso terapêutico , HumanosRESUMO
MIC values for amphotericin B and three azoles determined by the EUCAST reference technique and by gradient concentration strips were compared for 30 Mucorales isolates belonging to clinically important species. Essential agreement (EA) within ±2 dilution steps at 24 hours between the techniques was 83.3% for isavuconazole. EAs for itraconazole, amphotericin B, and posaconazole were 86.7%, 73.3%, and 56.7%, respectively. A good agreement was obtained between visual and spectrophotometric readings for EUCAST.
Assuntos
Antifúngicos/uso terapêutico , Mucorales/efeitos dos fármacos , Nitrilas/uso terapêutico , Piridinas/uso terapêutico , Triazóis/uso terapêutico , Anfotericina B/uso terapêutico , Azóis/uso terapêutico , Humanos , Itraconazol/uso terapêutico , Testes de Sensibilidade MicrobianaRESUMO
BACKGROUND: This study investigated predominant microorganisms causing community-onset bacteraemia at the medical emergency department (ED) of a tertiary-care university hospital in Germany from 2013 to 2018 and their antimicrobial susceptibility patterns. METHODS: Antimicrobial resistance patterns in patients with positive blood cultures presenting to an internal medicine ED were retrospectively analysed. RESULTS: Blood cultures were obtained at 5191 of 66,879 ED encounters, with 1013 (19.5%) positive results, and true positive results at 740 encounters (diagnostic yield, 14.3%). The most frequently isolated relevant microorganisms were Enterobacterales (n = 439, 59.3%), Staphylococcus aureus (n = 92, 12.4%), Streptococcus pneumoniae (n = 34, 4.6%), Pseudomonas aeruginosa (n = 32, 4.3%), Streptococcus pyogenes (n = 16, 2.2%), Enterococcus faecalis (n = 18, 2.4%), and Enterococcus faecium (n = 12, 1.6%). Antimicrobial susceptibility testing revealed a high proportion of resistance against ampicillin-sulbactam in Enterobacterales (42.2%). The rate of methicillin-resistant Staphylococcus aureus was low (0.4%). Piperacillin-tazobactam therapy provided coverage for 83.2% of all relevant pathogens using conventional breakpoints. Application of the new European Committee on Antimicrobial Susceptibility Testing (EUCAST) recommendations increased the percentage of susceptible isolates to high-dose piperacillin-tazobactam to 92.8% (p < 0.001). Broad-spectrum carbapenems would only cover an additional 4.8%. The addition of vancomycin or linezolid extended coverage by just 1.7%. CONCLUSIONS: Using an ureidopenicillin-beta-lactamase inhibitor combination at the high dose suggested by the new EUCAST recommendations provided nearly 93% coverage for relevant pathogens in patients with suspected bloodstream infection in our cohort. This might offer a safe option to reduce the empiric use of carbapenems. Our data support the absence of a general need for glycopeptides or oxazolidinones in empiric treatment.
Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Carbapenêmicos/uso terapêutico , Farmacorresistência Bacteriana/efeitos dos fármacos , Piperacilina/uso terapêutico , Tazobactam/uso terapêutico , Antibacterianos/efeitos adversos , Carbapenêmicos/efeitos adversos , Serviço Hospitalar de Emergência , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Alemanha , Hospitais Universitários , Humanos , Testes de Sensibilidade Microbiana , Piperacilina/efeitos adversos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Estudos Retrospectivos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Tazobactam/efeitos adversos , Resultado do TratamentoRESUMO
To evaluate the association between appropriate antifungal treatment and mortality among patients with candidemia using different breakpoint definitions. In a retrospective study, we included all adults with candidemia in a tertiary center between 2009 and 2015. We defined three versions of appropriate (covering) antifungal treatment, according to Clinical and Laboratory Standards Institute (CLSI) 2008, CLSI 2012, and European Committee on Antimicrobial Susceptibility Testing (EUCAST) (2017 update) breakpoints. For empiric treatment, we evaluated the association with 30-day mortality. For definitive treatment, we evaluated the association with 90-day mortality among patients surviving the first week after candidemia onset. Adjusted odds ratios (OR) from a bivariate logistic regression with 95% confidence intervals are reported. We identified 302 patients with 308 separate candidemia episodes. The crude 30-day mortality was 55% (168/308). Resistance to anidulafungin increased from 3.5 to 51.6% and to fluconazole from 15.2 to 44.1%, when applying CLSI 2008 and EUCAST definitions, respectively. Appropriate empirical treatment was significantly associated with lower 30-day mortality using the CLSI 2008 definitions, adjusted OR 0.56 (0.33-0.96). The associations were similar, though not statistically significant for EUCAST, 0.58 (0.33-1.00), and CLSI 2012, OR 0.62 (0.37-1.04). Appropriate definitive treatment according to CLSI 2012 and EUCAST was independently associated with lower 90-day mortality, ORs 0.31 (0.13-0.75) and 0.44 (0.23-0.8), respectively. With CLSI 2008, the association was similar but not statistically significant, OR 0.4 (0.11-1.41), with few isolates classified as resistant. Considering the major shift in resistance prevalence when applying CLSI 2008, CLSI 2012, and EUCAST breakpoint definitions, no major differences were observed in their association with mortality.
Assuntos
Antifúngicos/uso terapêutico , Candidemia/tratamento farmacológico , Candidemia/mortalidade , Idoso , Candida/isolamento & purificação , Farmacorresistência Fúngica , Feminino , Fluconazol/uso terapêutico , Humanos , Modelos Logísticos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Razão de Chances , Estudos Retrospectivos , Resultado do TratamentoRESUMO
BACKGROUND: As many clinical laboratories convert between Stokes, Clinical and Laboratory Standards Institute (CLSI) and European Committee for Antimicrobial Susceptibility Testing (EUCAST) methods, the problem of comparing differently derived sets of antimicrobial susceptibility testing (AST) data with each other arises, owing to a scarcity of knowledge of inter-method comparability. The purpose of the current study was to determine the comparability of CLSI, EUCAST and Stokes AST methods for determining susceptibility of uropathogenic Escherichia coli to ampicillin, amoxicillin-clavulanate, trimethoprim, cephradine/cephalexin, ciprofloxacin and nitrofurantoin. METHODS: A total of 100 E. coli isolates were obtained from boric acid urine samples from patients attending GP surgeries. For EUCAST and CLSI, the Kirby-Bauer disc diffusion method was used and results interpreted using the respective breakpoint guidelines. For the Stokes method, direct susceptibility testing was performed on the urine samples. RESULTS: The lowest levels of agreement were for amoxicillin-clavulanate (60%) and ciprofloxacin (89%) between the three AST methods, when using 2017 interpretive guidelines for CLSI and EUCAST. A comparison of EUCAST and CLSI without Stokes showed 82% agreement for amoxicillin-clavulanate and 94% agreement for ciprofloxacin. Discrepancies were compounded by varying breakpoint susceptibility guidelines issued during the period 2011-2017, and through the inclusion of a definition of intermediate susceptibility in some cases. CONCLUSIONS: Our data indicate that the discrepancies generated through using different AST methods and different interpretive guidelines may result in confusion and inaccuracy when prescribing treatment for urinary tract infection.
Assuntos
Antibacterianos/uso terapêutico , Bacteriúria/tratamento farmacológico , Infecções por Escherichia coli/tratamento farmacológico , Infecções Urinárias/tratamento farmacológico , Escherichia coli Uropatogênica/efeitos dos fármacos , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Ampicilina/uso terapêutico , Bacteriúria/diagnóstico , Bacteriúria/microbiologia , Cefalexina/uso terapêutico , Cefradina/uso terapêutico , Ciprofloxacina/uso terapêutico , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/microbiologia , Humanos , Testes de Sensibilidade Microbiana/normas , Nitrofurantoína/uso terapêutico , Guias de Prática Clínica como Assunto , Trimetoprima/uso terapêutico , Infecções Urinárias/diagnóstico , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/crescimento & desenvolvimento , Escherichia coli Uropatogênica/isolamento & purificaçãoRESUMO
Increases in antibiotic minimum inhibitory concentrations (MICs) for Pseudomonas aeruginosa during treatment are commonly observed but their relationship to efflux overexpression remains poorly documented. In this study, pairs of first [at time of diagnosis (D0)] and last [during treatment (DL)] P. aeruginosa isolates were obtained from patients treated for suspicion of nosocomial pneumonia. Pair clonality was determined by repetitive extragenic palindromic PCR. Overexpression of mexA and mexX was assessed by real-time PCR, and expression of mexC and mexE was assessed by PCR. Antibiotics received by patients before and during treatment were determined from clinical charts. For D0 isolates, 24% were from patients without antibiotics for 1 month and 64% were negative for mexA/mexX overexpression and mexC/mexE expression. For DL isolates, approximately one-half of the patients had received piperacillin/tazobactam, amikacin, meropenem and/or cefepime, and 17% had received ciprofloxacin (alone or in combination); 38% did not show changes in expression of the four genes, whereas 38% showed increased expression for one gene (mainly mexA or mexX), 19% for two genes (mainly mexA and mexX) and 5% for three or four genes. Isolates overexpressing mexA or mexX had median MICs above EUCAST clinical resistance breakpoints for ciprofloxacin, cefepime and meropenem, or for ciprofloxacin, amikacin, cefepime and meropenem, respectively. mexA or mexX overexpression was statistically significantly associated with patients' exposure to ciprofloxacin and meropenem or cefepime and meropenem, respectively. Overexpression of genes encoding antibiotic transporters in P. aeruginosa during treatment is frequent and is associated with increases in MICs above EUCAST clinical susceptibility breakpoints.