Antifungal Susceptibility Testing of Aspergillus spp. by Using a Composite Correlation Index (CCI)-Based Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Method Appears To Not Offer Benefit over Traditional Broth Microdilution Testing

Gitman, Melissa R.; McTaggart, Lisa R.; Spinato, Joanna; Poopalarajah, Rahgavi; Lister, Erin; Husain, Shahid; Kus, Julianne V.

doi:10.1128/jcm.00254-17

Cited by 19 publications

(34 citation statements)

References 24 publications

(27 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…including A. fumigatus [40]. In a proof-of-concept study, MALDI-TOF MS was shown to accurately detect strains of A. fumigatus with reduced voriconazole susceptibility, although this method did not prove to be more rapid or simpler compared to testing with PCR and the Sensititre® microdilution panel [41]. Still, this method needs improved standardization, expanded availability of databases, and databases need to be continuously updated to include reference spectra of unusual pathogens [42, 43].…”

Section: Culture-based Methods For Detection Of Resistance In Aspergimentioning

confidence: 99%

(New) Methods for Detection of Aspergillus fumigatus Resistance in Clinical Samples

Jenks

Spieß

Buchheidt

et al. 2019

Curr Fungal Infect Rep

View full text Add to dashboard Cite

Purpose of Review The incidence of invasive aspergillosis has increased substantially over the past few decades, accompanied by a change in susceptibility patterns of Aspergillus fumigatus with increasing resistance observed against triazole antifungals, including voriconazole and isavuconazole, the most commonly used antifungal agents for the disease. Culture-based methods for determining triazole resistance are still the gold standard but are time consuming and lack sensitivity. We sought to provide an update on non-culture-based methods for detecting resistance patterns to Aspergillus. Recent Findings New molecular-based approaches for detecting triazole resistance to Aspergillus, real-time polymerase chain reaction (PCR) to detect mutations to the Cyp51A protein, have been developed which are able to detect most triazole-resistant A. fumigatus strains in patients with invasive aspergillosis. Summary Over the last few years, a number of non-culture-based methods for molecular detection of Aspergillus triazole resistance have been developed that may overcome some of the limitations of culture. These molecular methods are therefore of high epidemiological and clinical relevance, mainly in immunocompromised patients with hematological malignancies, where culture has particularly limited sensitivity. These assays are now able to detect most triazole-resistant Aspergillus fumigatus strains. Given that resistance rates vary, clinical utility for these assays still depends on regional resistance patterns.

show abstract

Section: Culture-based Methods For Detection Of Resistance In Aspergimentioning

confidence: 99%

(New) Methods for Detection of Aspergillus fumigatus Resistance in Clinical Samples

Jenks

Spieß

Buchheidt

et al. 2019

Curr Fungal Infect Rep

View full text Add to dashboard Cite

show abstract

“…In line with our studies [ 67 , 68 , 69 ], slightly longer incubation times (30 and 48 h) allowed for accurate detection of isolates as WT or non-WT by MS-AFST, in complete agreement with the CYP51A gene sequence analysis results. Remarkably, using the “three-point” assay (no drug, 16 μg/mL voriconazole, and voriconazole ECV), the authors [ 73 ] obtained the same findings, requiring 30 to 48 h of incubation with the drug prior to MALDI-TOF MS analysis. It is likely that some fungal isolates requiring additional time relates to the impossibility of their reaching enough growth and, consequently, level of expressed proteins to allow for correct classification by the MS-AFST assay [ 69 , 73 ].…”

Section: Nonconventional Phenotypic Assays For Testing Fungal Suscmentioning

confidence: 80%

“…Remarkably, using the “three-point” assay (no drug, 16 μg/mL voriconazole, and voriconazole ECV), the authors [ 73 ] obtained the same findings, requiring 30 to 48 h of incubation with the drug prior to MALDI-TOF MS analysis. It is likely that some fungal isolates requiring additional time relates to the impossibility of their reaching enough growth and, consequently, level of expressed proteins to allow for correct classification by the MS-AFST assay [ 69 , 73 ].…”

Section: Nonconventional Phenotypic Assays For Testing Fungal Suscmentioning

confidence: 80%

“…Contemporarily, but independently from us, Gitman et al [ 73 ] explored the MALDI-TOF MS–based method to differentiate WT (no acquired resistance) from non-WT (acquired resistance) isolates of 20 Aspergillus species (including 17 A. fumigatus ) with respect to voriconazole (MIC > ECV; 1 μg/mL). Four of 17 A. fumigatus were phenotypically and genotypically resistant to voriconazole, whereas two isolates of Aspergillus ustus and one isolate of Aspergillus calidoustus served as controls due to their intrinsic low azole susceptibility.…”

Section: Nonconventional Phenotypic Assays For Testing Fungal Suscmentioning

confidence: 99%

See 1 more Smart Citation

Susceptibility Testing of Fungi to Antifungal Drugs

Sanguinetti

2018

JoF

View full text Add to dashboard Cite

Susceptibility testing of fungi against antifungal drugs commonly used for therapy is a key component of the care of patients with invasive fungal infections. Antifungal susceptibility testing (AFST) has progressed in recent decades to finally become standardized and available as both Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) reference methods and in commercial manual/automated phenotypic methods. In clinical practice, the Sensititre YeastOne and Etest methods are widely used for AFST, particularly for sterile site isolates of Candida. Nevertheless, AFST is moving toward new phenotypic methods, such as matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), that are capable of providing rapid, and potentially more actionable, results for the treating clinician. Our objective is to summarize updated data on phenotypic methods for AFST of Candida and Aspergillus species and to assess their significance in view of opposing, but emerging, molecular genotypic methods.

show abstract

“…Spectra from different concentrations of the antifungal substance are used to create a composite correlation index (CCI) and thereby infer a Minimal Profile Change Concentration (MPCC) analogous to an MIC value. Some studies also evaluated a simplified three-point assay, in which fungal spectra at the breakpoint concentration were compared to a maximum concentration as well as a drug-free control, and were then classified into resistant or susceptible depending upon their similarity to one of the extremes [ 16 , 21 , 23 , 25 , 30 ]. However, while the hands-on time is somewhat shortened, the time to result mainly depends on the incubation time, and is thereby not abbreviated.…”

Section: Discussionmentioning

confidence: 99%

Rapid Antifungal Susceptibility Testing of Yeasts and Molds by MALDI-TOF MS: A Systematic Review and Meta-Analysis

Knoll

Ulmer

Lass‐Flörl

2021

JoF

View full text Add to dashboard Cite

Due to the growing burden of fungal infections and a recent rise in antifungal resistance, antifungal susceptibility testing (AFST) is of increasing importance. The common methods of AFST have turnaround times of 24 to 48 h, and the available rapid methods are limited by applicability, cost-efficiency or accuracy. Given the urgency of adequate antifungal treatment in invasive mycoses, the need for the rapid and reliable detection of resistance is evident. In this systematic review and meta-analysis, we evaluated the diagnostic accuracy of AFST based on matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). Twelve studies were reviewed, and data for the comparative analysis of their accuracy and methodology were systematically extracted. Compared to broth dilution as the gold standard, MALDI-TOF MS-based AFST reached a pooled sensitivity and specificity of 91% (95% Confidence Interval [CI], 84% to 96%) and 95% (95% CI, 90% to 98%), respectively. A comparative analysis showed that the sensitivity was higher for the semi-quantitative matrix-assisted laser desorption ionization Biotyper antibiotic susceptibility test rapid assay (MBT ASTRA) technique (96%) than for the correlate composite index (CCI) approach (85%), which is based on spectrum changes. Turnaround times below eight hours reached better diagnostic values than longer incubation periods, qualifying MALDI-TOF MS-based AFST as a rapid and accurate method for the detection of antifungal resistance.

show abstract

Antifungal Susceptibility Testing of Aspergillus spp. by Using a Composite Correlation Index (CCI)-Based Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Method Appears To Not Offer Benefit over Traditional Broth Microdilution Testing

Cited by 19 publications

References 24 publications

(New) Methods for Detection of Aspergillus fumigatus Resistance in Clinical Samples

(New) Methods for Detection of Aspergillus fumigatus Resistance in Clinical Samples

Susceptibility Testing of Fungi to Antifungal Drugs

Rapid Antifungal Susceptibility Testing of Yeasts and Molds by MALDI-TOF MS: A Systematic Review and Meta-Analysis

Contact Info

Product

Resources

About