Comparison of the Vitek 2 Antifungal Susceptibility System with the Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) Broth Microdilution Reference Methods and with the Sensititre YeastOne and Etest Techniques for
            <i>In Vitro</i>
            Detection of Antifungal Resistance in Yeast Isolates

Cuenca‐Estrella, Manuel; Gómez-López, Alicia; Alastruey‐Izquierdo, Ana; Bernal‐Martínez, Leticia; Cuesta, Isabel; Buitrago, María J.; Rodríguez-Tudela, Juan Luis

doi:10.1128/jcm.02316-09

Cited by 151 publications

(117 citation statements)

References 15 publications

Supporting

Mentioning

103

Contrasting

Unclassified

Order By: Relevance

“…Comparisons of the performance of SQ and SYO have not yet been reported and should be determined. However, several studies have reported that the SYO method achieves excellent results in terms of reproducibility and CAs with both the EUCAST BMD protocol and the CLSI broth microdilution reference method (19,20,32,(34)(35)(36).…”

Section: Discussionmentioning

confidence: 99%

Comparative Evaluation of a New Commercial Colorimetric Microdilution Assay (SensiQuattro Candida EU) with MIC Test Strip and EUCAST Broth Microdilution Methods for Susceptibility Testing of Invasive Candida Isolates

et al. 2015

View full text Add to dashboard Cite

Candidemia is an important cause of morbidity and mortality in immunosuppressed patients. Candida isolates must be cultivated, identified, and tested for susceptibility. We compared the performance of a new colorimetric broth microdilution panel (SensiQuattro Candida EU) for antifungal susceptibility testing to that of Liofilchem's MIC test strip and the EUCAST reference broth microdilution protocol. We tested 187 blood culture isolates of 5 Candida spp. (120 C. albicans, 38 C. glabrata, 10 C. parapsilosis, 12 C. tropicalis, and 7 C. krusei) against seven antifungal agents (amphotericin B, fluconazole, voriconazole, posaconazole, caspofungin, anidulafungin, and micafungin) and interpreted the MICs according to the EUCAST recommendations. If applicable, the overall essential agreement (EA) of the SensiQuattro panel with the reference broth microdilution was slightly higher for C. albicans (87%) than for other species (85.8%). We found that SensiQuattro performed best in testing amphotericin B (EA, 100%), voriconazole (EA, 93.7%), and posaconazole (EA, 94.8%) against C. albicans, but its error rate for this species was high (29.6%) because of mainly major errors (26.7%) in testing anidulafungin and micafungin. Compared to the SensiQuattro panel, the MIC test strip exhibited a higher level of agreement for most isolates. SensiQuattro assays are easy to perform, but they are currently not suitable for testing echinocandins against Candida spp. Bloodstream infections caused by Candida spp. are the most common invasive fungal infections (1, 2). Patients at risk of candidemia are those who are immunocompromised, e.g., those with hematologic and solid-organ malignancies, those receiving immunosuppressive therapy, those with chronic renal failure, and those treated with antibiotics or invasive catheters (2, 3). In the population of the United States, the incidence of hospital-acquired candidemia is as high as 10 cases per 100,000 patients (4). The 2013 annual epidemiological report of the European Centre for Disease Prevention and Control (ECDC) stated that Candida spp. are the fifth most frequently isolated microorganism in intensive care unit (ICU)-acquired bloodstream infections in the European Union (5). Mortality rates due to Candida bloodstream infections vary from 45% to 53% depending on the population investigated (6, 7). Although C. albicans is still the most frequently isolated Candida species in candidemia, non-albicans Candida species are increasingly found to be the causative agents (8-12).Of particular concern is emerging resistance to both the antifungal classes of azoles and the newer echinocandins, as recently reported in the World Health Organization's "Antimicrobial Resistance: Global Report on Surveillance 2014" (13). Resistance to antifungal drugs varies among the various species of Candida because of the intrinsically low susceptibility of C. glabrata to azole antifungals, such as fluconazole (FLC) (14), and because of multifactorial processes or mutations in the fks1 and fks2 genes (15,16). For the...

show abstract

Section: Discussionmentioning

confidence: 99%

Comparative Evaluation of a New Commercial Colorimetric Microdilution Assay (SensiQuattro Candida EU) with MIC Test Strip and EUCAST Broth Microdilution Methods for Susceptibility Testing of Invasive Candida Isolates

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Buona concordanza è stata riscontrata per amfotericina B (97.4-97.9%) e 5-fluorocitosina (95.2-96%), rispettivamente con CLSI e con EUCAST, ma non ci sono studi dettagliati ripartiti per specie (14 itraconazolo e pressoché assoluta per voriconazolo permette di interpretare queste molecole con i CBP proposti da EUCAST/CLSI. In assenza di breakpoints clinici specifici con il metodo YeastOne, sono stati determinati i cutoff epidemiologici di fluconazolo, itraconazolo, posaconazolo, voriconazolo, echinocandine, AMB e 5-fluorocitosina, per sei specie di Candida e questi valori possono essere utili come tentativo per monitorare l'emergenza di resistenze quando la metodica utilizzata è il YeastOne.…”

Section: Come Sono Le Mics Dei Breakpoint Clinici E Quindi Le Interprunclassified

“…Etest ® Buona concordanza è stata rilevata tra CLSI ed EUCAST per amfotericina B (>97%) e gli azoli (>95%), ma non ci sono studi ripartiti per specie (14). L'Etest, utilizzato nel laboratorio clinico, mostra una concordanza complessiva per AMB, fluconazolo, itraconazolo, voriconazolo, 5-fluorocitosina e caspofungina, con il metodo di riferimento EUCAST pari al 71%, che è più elevata per voriconazolo (86.6%) e più bassa per itraconazolo (59.6%) (16).…”

Section: Antifungino Specie Eucast (V 70) Clsi (A27-s4)unclassified

See 1 more Smart Citation

Antifungal susceptibility testing of Candida in the Clinical Laboratory: how to do it, when to do it, and how to interpret it

et al. 2014

View full text Add to dashboard Cite

SummaryAntifungal susceptibility testing of Candida in the Clinical Laboratory: how to do it, when to do it, and how to interpret it.Significant changes in the management of fungaemia have occurred in the last decade with increased use of fluconazole prophylaxis, of empirical treatment and of echinocandins as first-line agents for documented disease. The emergence of drug resistance in fungal pathogens has a profound impact on human health given limited number of antifungal drugs. Antifungal resistance in Candida may be either intrinsic or acquired and may be encountered in the antifungal drug exposed but also the antifungal drug naïve patient The variation in resistance rates between centers emphasizes that it is essential to have knowledge of the local Candida species distribution and antifungal resistance rates to guide initial therapy for Candida BSI. Moreover, all Candida isolates from blood and normally sterile sites should be identified to the species level. The Clinical and Laboratory Standards Institute and European Committee on Antimicrobial Susceptibility Testing have developed breakpoints and epidemiological cutoff values that are now established for Candida spp. Clinical microbiology laboratories will be employed commercial susceptibility assays, rather than reference broth microdilution methods and comparative studies are particularly important. Vitek 2 ® , Etest ® and Sensititre YeastOne ® provided a high degree of essential agreement and comparable sensitivity and specificity to BMD-RPMI for identifying resistance to azole and echinocandins in Candida spp. IntroduzioneL'elevato tasso di mortalità associato alle infezioni invasive da Candida ed alle candidemie, insieme ad un ritardo della terapia antifungina e ad una diagnosi non ottimale, ha determinato un uso eccessivo di farmaci antifungini sia per la terapia che per la profilassi di queste infezioni. Candida albicans rimane la specie di più frequente riscontro: tuttavia altre specie, quali C. tropicalis, C. parapsilosis, C. glabrata e C. krusei, la cui sensibilità agli agenti antifungini disponibili risulta spesso variabile, risultano in sensibile aumento. La resistenza al fluconazolo nelle specie di Candida è ritenuta essere una grave minaccia negli USA per la gestione dei singoli casi e quale evento epidemiologico di rilievo. C. glabrata e C. parapsilosis rappresentano le due specie con ridotta sensibilità rispettivamente agli azoli ed alle echinocandine di più frequente riscontro. Di recente, in due importanti studi di sorveglianza, è stata osservata una diminuzione della sensibilità alle echinocandine nei ceppi di C. glabrata resistenti al fluconazolo (2,25,32).La recente introduzione di nuove molecole antifungine meno tossiche, pur contribuendo a migliorare sostanzialmente la gestione clinico-terapeutica dei pazienti, ha sollevato la questione della scelta del regime terapeutico più appropriato. L'incremento delle infezioni fun-

show abstract

“…The recent introduction of the Vitek 2 yeast susceptibility test (bioMérieux, Inc.) has provided a completely automated means of performing antifungal susceptibility testing of yeasts that has been shown to produce reproducible, rapid, and accurate results consistent with those obtained with the CLSI reference broth microdilution (BMD) method for amphotericin B, flucytosine, fluconazole, and voriconazole (4)(5)(6)(7)(8)(9). The ease of performing antifungal susceptibility testing provided by the Vitek 2 system offers the possibility of performing this testing to laboratories that previously had not done so because of the manual nature of the available methods.…”

mentioning

confidence: 94%

Multicenter Evaluation of the New Vitek 2 Yeast Susceptibility Test Using New CLSI Clinical Breakpoints for Fluconazole

et al. 2014

View full text Add to dashboard Cite

A fully automated antifungal susceptibility test system recently updated to reflect the new species-specific clinical breakpoints (CBPs) of fluconazole for Candida (Vitek 2 AF03 yeast susceptibility test; bioMérieux, Inc., Durham, NC) was compared in three different laboratories with the Clinical and Laboratory Standards Institute (CLSI) reference broth microdilution (BMD) method by testing 2 quality control strains, 10 reproducibility strains (4 Candida species and 6 Cryptococcus neoformans strains), and 746 isolates of Candida species (702 isolates, 13 species) and 44 isolates of C. neoformans against fluconazole. Excellent essential agreement (EA) (within 2 dilutions) between the reference and Vitek 2 MICs was observed for fluconazole and Candida species (94.0%). The EA was lower for fluconazole and C. neoformans at 86.4%. The mean times to a result with the Vitek 2 test were 9.1 h for Candida species and 12.1 h for C. neoformans. Categorical agreement (CA) between the two methods was assessed by using the new species-specific CBPs. For less common species without fluconazole CBPs, the epidemiological cutoff values (ECVs) were used to differentiate wild-type (WT; MIC, ECV) strains. The CAs between the two methods were 92.0% for Candida species (0.3% very major errors [VME] and 2.6% major errors [ME]) and 84.1% for C. neoformans (4.5% VME and 11.4% ME). The updated Vitek 2 AF03 IUO yeast susceptibility system is comparable to the CLSI BMD reference method for testing the susceptibility of clinically important yeasts to fluconazole when using the new (lower) CBPs and ECVs.T he automation of laboratory testing has clear advantages in test standardization, reproducibility and timeliness of results, and savings in labor and reagents (1, 2). Whereas total laboratory automation has been slow to arrive in clinical microbiology laboratories, automated microbial identification and antimicrobial susceptibility testing systems are widely used in microbiology laboratories (1, 2). These systems have been broadly applied in the testing of bacteria but, aside from the identification of yeasts, have not been useful for fungi (2).Antifungal susceptibility testing of Candida species and Cryptococcus neoformans has been standardized by the Clinical and Laboratory Standards Institute (CLSI) Subcommittee on Antifungal Susceptibility Testing (3), and until recently, the only commercially available methods for performing such testing have been manual methods such as the Sensititre Yeast One (TREK Diagnostic Systems, Cleveland, OH) and the Etest (bioMérieux, Inc., Durham, NC). The recent introduction of the Vitek 2 yeast susceptibility test (bioMérieux, Inc.) has provided a completely automated means of performing antifungal susceptibility testing of yeasts that has been shown to produce reproducible, rapid, and accurate results consistent with those obtained with the CLSI reference broth microdilution (BMD) method for amphotericin B, flucytosine, fluconazole, and voriconazole (4-9). The ease of performing an...

show abstract

Cited by 151 publications

References 15 publications

Comparative Evaluation of a New Commercial Colorimetric Microdilution Assay (SensiQuattro Candida EU) with MIC Test Strip and EUCAST Broth Microdilution Methods for Susceptibility Testing of Invasive Candida Isolates

Comparative Evaluation of a New Commercial Colorimetric Microdilution Assay (SensiQuattro Candida EU) with MIC Test Strip and EUCAST Broth Microdilution Methods for Susceptibility Testing of Invasive Candida Isolates

Antifungal susceptibility testing of Candida in the Clinical Laboratory: how to do it, when to do it, and how to interpret it

Multicenter Evaluation of the New Vitek 2 Yeast Susceptibility Test Using New CLSI Clinical Breakpoints for Fluconazole

Contact Info

Product

Resources

About