Emerging Terbinafine Resistance in Trichophyton: Clinical Characteristics, Squalene Epoxidase Gene Mutations, and a Reliable EUCAST Method for Detection

ABSTRACT In recent years, cases involving terbinafine-resistant Trichophyton isolates have been reported increasingly, particularly in India. We present 14 cases of terbinafine treatment failure in Trichophyton-infected Danish patients due to acquired resistance. Patients infected with Trichophyton rubrum (n = 12) or Trichophyton interdigitale (n = 2) with elevated terbinafine MICs during 2013–2018 were included. Antifungal susceptibility testing (AFST) was performed following a modified EUCAST E.Def 9.3.1 method (5 days of incubation) with or without cycloheximide and chloramphenicol (CC) supplementation of the growth medium. The squalene epoxidase (SE) target gene was sequenced, and 3-dimensional enzyme homology modeling was performed. Most patients (12/14 [86%]) were male. The mean age was 53.5 years (range, 11 to 77 years). The mean duration of infections was 4.8 years at the time of resistance detection. Prior systemic terbinafine treatment was documented for all patients, and topical therapy for 62% (information was missing in one case). Overall, nine isolates (64%) displayed high terbinafine resistance (MICs, 4 to >8 mg/liter), while two (14%) displayed moderate (MICs, 1 to 2 mg/liter) and three (21%) displayed low (MICs, 0.125 to 0.25 mg/liter) terbinafine resistance compared with control isolates. MICs generated with or without CC supplementation were similar, but CC prevented contamination. Known and novel SE amino acid substitutions (F397L, L393F, L393S, F415S, H440Y F484Y, and I121M V237I) were detected in resistant but not control isolates. Three-dimensional homology modeling suggested a role of the novel I121M and V237I alterations. Terbinafine resistance has been detected in Denmark using a modified EUCAST method, which facilitated susceptibility testing of dermatophytes. Action is needed for this emerging public health problem.

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Mutation in the Squalene Epoxidase Gene ofTrichophyton interdigitaleandTrichophyton rubrumAssociated with Allylamine Resistance

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02522-17 ◽

2018 ◽

Vol 62 (5) ◽

Cited By ~ 54

Author(s):

Shivaprakash M. Rudramurthy ◽

Shamanth A. Shankarnarayan ◽

Sunil Dogra ◽

Dipika Shaw ◽

Khurram Mushtaq ◽

...

Keyword(s):

Antifungal Agents ◽

Susceptibility Testing ◽

Trichophyton Rubrum ◽

Antifungal Susceptibility ◽

Ergosterol Biosynthesis ◽

Squalene Epoxidase ◽

Biosynthesis Pathway ◽

Wild Type ◽

Content Type ◽

Recent Attention

ABSTRACTDermatophytosis, the commonest superficial fungal infection, has gained recent attention due to its change of epidemiology and treatment failures. Despite the availability of several agents effective against dermatophytes, the incidences of chronic infection, reinfection, and treatment failures are on the rise.Trichophyton rubrumandTrichophyton interdigitaleare the two species most frequently identified among clinical isolates in India. Consecutive patients (n= 195) with suspected dermatophytosis during the second half of 2014 were included in this study. Patients were categorized into relapse and new cases according to standard definitions. Antifungal susceptibility testing of the isolatedTrichophytonspecies (n= 127) was carried out with 12 antifungal agents: fluconazole, voriconazole, itraconazole, ketoconazole, sertaconazole, clotrimazole, terbinafine, naftifine, amorolfine, ciclopirox olamine, griseofulvin, and luliconazole. The squalene epoxidase gene was evaluated for mutation (if any) in 15T. interdigitaleand 5T. rubrumisolates exhibiting high MICs for terbinafine. A T1189C mutation was observed in fourT. interdigitaleand twoT. rubrumisolates. This transition leads to the change of phenylalanine to leucine in the 397th position of the squalene epoxidase enzyme. In homology modeling the mutant residue was smaller than the wild type and positioned in the dominant site of squalene epoxidase during drug interaction, which may lead to a failure to block the ergosterol biosynthesis pathway by the antifungal drug.

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The Emerging Terbinafine-Resistant Trichophyton Epidemic: What Is the Role of Antifungal Susceptibility Testing?

Dermatology ◽

10.1159/000515290 ◽

2021 ◽

pp. 1-20

Author(s):

Julia J. Shen ◽

Maiken C. Arendrup ◽

Shyam Verma ◽

Ditte Marie L. Saunte

Keyword(s):

Gene Mutation ◽

Susceptibility Testing ◽

Geometric Mean ◽

Antifungal Susceptibility ◽

Antifungal Susceptibility Testing ◽

Squalene Epoxidase ◽

Exclusion Criteria ◽

Huge Variation

Background: Dermatophytosis is commonly encountered in the dermatological clinics. The main aetiological agents in dermatophytosis of skin and nails in humans are Trichophyton (T.) rubrum, T. mentagrophytes and T. interdigitale (former T. mentagrophytes-complex). Terbinafine therapy is usually effective in eradicating infections due to these species by inhibiting their squalene epoxidase (SQLE) enzyme, but increasing numbers of clinically resistant cases and mutations in the SQLE gene have been documented recently. Resistance to antimycotics is phenotypically determined by antifungal susceptibility testing (AFST). However, AFST is not routinely performed for dermatophytes and no breakpoints classifying isolates as susceptible or resistant are available, making it difficult to interpret the clinical impact of a minimal inhibitory concentration (MIC). Summary: PubMed was systematically searched for terbinafine susceptibility testing of dermatophytes on October 20, 2020, by two individual researchers. The inclusion criteria were in vitro terbinafine susceptibility testing of Trichophyton (T.) rubrum, T. mentagrophytes and T. interdigitale with the broth microdilution technique. The exclusion criteria were non-English written papers. Outcomes were reported as MIC range, geometric mean, modal MIC and MIC50 and MIC90 in which 50 or 90% of isolates were inhibited, respectively. The reported MICs ranged from <0.001 to >64 mg/L. The huge variation in MIC is partly explained by the heterogeneity of the Trichophyton isolates, where some originated from routine specimens (wild types) whereas others came from non-responding patients with a known SQLE gene mutation. Another reason for the great variation in MIC is the use of different AFST methods where MIC values are not directly comparable. High MICs were reported particularly in isolates with SQLE gene mutation. The following SQLE alterations were reported: F397L, L393F, L393S, H440Y, F393I, F393V, F415I, F415S, F415V, S443P, A448T, L335F/A448T, S395P/A448T, L393S/A448T, Q408L/A448T, F397L/A448T, I121M/V237I and H440Y/F484Y in terbinafine-resistant isolates.

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An Improved Medium for Colistin Susceptibility Testing

Journal of Clinical Microbiology ◽

10.1128/jcm.01950-17 ◽

2018 ◽

Vol 56 (5) ◽

Cited By ~ 10

Author(s):

Konrad Gwozdzinski ◽

Saina Azarderakhsh ◽

Can Imirzalioglu ◽

Linda Falgenhauer ◽

Trinad Chakraborty

Keyword(s):

Susceptibility Testing ◽

Acquired Resistance ◽

Multidrug Resistant ◽

Colistin Resistance ◽

Reliable Determination ◽

Content Type ◽

E Coli ◽

Resistant Species ◽

Mueller Hinton ◽

Serovar Typhimurium

ABSTRACTThe plasmid-located colistin resistance genemcr-1confers low-level resistance to colistin, a last-line antibiotic against multidrug-resistant Gram-negative bacteria. Current CLSI-EUCAST recommendations require the use of a broth microdilution (BMD) method with cation-adjusted Mueller-Hinton (CA-MH) medium for colistin susceptibility testing, but approximately 15% of all MCR-1 producers are classified as sensitive in that broth. Here we report on an improved calcium-enhanced Mueller-Hinton (CE-MH) medium that permits simple and reliable determination ofmcr-1-containingEnterobacteriaceae. Colistin susceptibility testing was performed for 50mcr-1-containingEscherichia coliandKlebsiella pneumoniaeisolates, 7 intrinsically polymyxin-resistant species,K. pneumoniaeandE. coliisolates with acquired resistance to polymyxins due tomgrBandpmrBmutations, respectively, and 32mcr-1-negative, colistin-susceptible isolates ofAcinetobacter baumannii,Citrobacter freundii,Enterobacter cloacae,E. coli,K. pneumoniae, andSalmonella entericaserovar Typhimurium. A comparison of the colistin MICs determined in CA-MH medium and those obtained in CE-MH medium was performed using both the BMD and strip-based susceptibility test formats. We validated the data using an isogenic IncX4 plasmid lackingmcr-1. Use of the CE-MH broth provides clear separation between resistant and susceptible isolates in both BMD and gradient diffusion assays; this is true for bothmcr-1-containingEnterobacteriaceaeisolates and those exhibiting either intrinsic or acquired colistin resistance. CE-MH medium is simple to prepare and overcomes current problems associated with BMD and strip-based colistin susceptibility testing, and use of the medium is easy to implement in routine diagnostic laboratories, even in resource-poor settings.

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Antifungal Susceptibility Testing of Malassezia spp. with an Optimized Colorimetric Broth Microdilution Method

Journal of Clinical Microbiology ◽

10.1128/jcm.00338-17 ◽

2017 ◽

Vol 55 (6) ◽

pp. 1883-1893 ◽

Cited By ~ 22

Author(s):

Cheryl Leong ◽

Antonino Buttafuoco ◽

Martin Glatz ◽

Philipp P. Bosshard

Keyword(s):

Susceptibility Testing ◽

Skin Diseases ◽

Antifungal Susceptibility ◽

Drug Susceptibility ◽

Drug Susceptibility Testing ◽

Broth Microdilution ◽

Content Type ◽

Microdilution Method ◽

Broth Microdilution Method ◽

Colorimetric Indicator

ABSTRACTMalasseziais a genus of lipid-dependent yeasts. It is associated with common skin diseases such as pityriasis versicolor and atopic dermatitis and can cause systemic infections in immunocompromised individuals. Owing to the slow growth and lipid requirements of these fastidious yeasts, convenient and reliable antifungal drug susceptibility testing assays forMalasseziaspp. are not widely available. Therefore, we optimized a broth microdilution assay for the testing ofMalasseziathat is based on the CLSI and EUCAST assays forCandidaand other yeasts. The addition of ingredients such as lipids and esculin provided a broth medium formulation that enabled the growth of allMalasseziaspp. and could be read, with the colorimetric indicator resazurin, by visual and fluorescence readings. We tested the susceptibility of 52 strains of 13Malasseziaspecies to 11 commonly used antifungals. MIC values determined by visual readings were in good agreement with MIC values determined by fluorescence readings. The lowest MICs were found for the azoles itraconazole, posaconazole, and voriconazole, with MIC90values of 0.03 to 1.0 μg/ml, 0.06 to 0.5 μg/ml, and 0.03 to 2.0 μg/ml, respectively. AllMalasseziaspp. were resistant to echinocandins and griseofulvin. SomeMalasseziaspp. also showed high MIC values for ketoconazole, which is the most widely recommended topical antifungal to treatMalasseziaskin infections. In summary, our assay enables the fast and reliable susceptibility testing ofMalasseziaspp. with a large panel of different antifungals.

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A Revised Species Concept for OpportunisticMucorSpecies Reveals Species-Specific Antifungal Susceptibility Profiles

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00653-19 ◽

2019 ◽

Vol 63 (8) ◽

Cited By ~ 7

Author(s):

Lysett Wagner ◽

Sybren de Hoog ◽

Ana Alastruey-Izquierdo ◽

Kerstin Voigt ◽

Oliver Kurzai ◽

...

Keyword(s):

Amphotericin B ◽

Susceptibility Testing ◽

Species Concept ◽

Antifungal Susceptibility ◽

Content Type ◽

Mucor Indicus ◽

Species Specific ◽

Susceptibility Profiles ◽

High Mics

ABSTRACTRecently, the species concept of opportunisticMucor circinelloidesand its relatives has been revised, resulting in the recognition of its classical formae as independent species and the description of new species. In this study, we used isolates of all clinically relevantMucorspecies and performed susceptibility testing using the EUCAST reference method to identify potential species-specific susceptibility patterns.In vitrosusceptibility profiles of 101 mucoralean strains belonging to the genusMucor(72), the closely related speciesCokeromyces recurvatus(3),Rhizopus(12),Lichtheimia(10), andRhizomucor(4) to six antifungals (amphotericin B, natamycin, terbinaﬁne, isavuconazole, itraconazole, and posaconazole) were determined. The most active drug for all Mucorales was amphotericin B. Antifungal susceptibility profiles of pathogenicMucorspecies were specific for isavuconazole, itraconazole, and posaconazole. The species formerly united inM. circinelloidesshowed clear differences in their antifungal susceptibilities.Cokeromyces recurvatus,Mucor ardhlaengiktus,Mucor lusitanicus(M. circinelloidesf.lusitanicus), andMucor ramosissimusexhibited high MICs to all azoles tested.Mucor indicuspresented high MICs for isavuconazole and posaconazole, andMucor amphibiorumandMucor irregularisshowed high MICs for isavuconazole. MIC values ofMucorspp. for posaconazole, isavuconazole, and itraconazole were high compared to those forRhizopusand the Lichtheimiaceae (LichtheimiaandRhizomucor). Molecular identification combined within vitrosusceptibility testing is recommended forMucorspecies, especially if azoles are applied in treatment.

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Comparison of the Sensititre YeastOne and CLSI M38-A2 Microdilution Methods in Determining the Activity of Amphotericin B, Itraconazole, Voriconazole, and Posaconazole against Aspergillus Species

Journal of Clinical Microbiology ◽

10.1128/jcm.00780-18 ◽

2018 ◽

Vol 56 (10) ◽

Cited By ~ 7

Author(s):

Hsuan-Chen Wang ◽

Ming-I Hsieh ◽

Pui-Ching Choi ◽

Chi-Jung Wu

Keyword(s):

Aspergillus Fumigatus ◽

Amphotericin B ◽

Antifungal Agents ◽

Susceptibility Testing ◽

Geometric Mean ◽

Antifungal Susceptibility ◽

Reference Method ◽

Aspergillus Species ◽

Broth Microdilution ◽

Content Type

ABSTRACT This study compared the YeastOne and reference CLSI M38-A2 broth microdilution methods for antifungal susceptibility testing of Aspergillus species. The MICs of antifungal agents were determined for 100 Aspergillus isolates, including 54 Aspergillus fumigatus (24 TR34/L98H isolates), 23 A. flavus, 13 A. terreus, and 10 A. niger isolates. The overall agreement (within 2 2-fold dilutions) between the two methods was 100%, 95%, 92%, and 90% for voriconazole, posaconazole, itraconazole, and amphotericin B, respectively. The voriconazole geometric mean (GM) MICs were nearly identical for all isolates using both methods, whereas the itraconazole and posaconazole GM MICs obtained using the YeastOne method were approximately 1 dilution lower than those obtained using the reference method. In contrast, the amphotericin B GM MIC obtained using the YeastOne method was 3.3-fold higher than that observed using the reference method. For the 24 A. fumigatus TR34/L98H isolates assayed, the categorical agreement (classified according to the CLSI epidemiological cutoff values) was 100%, 87.5%, and 83.3% for itraconazole, voriconazole, and posaconazole, respectively. For four A. niger isolates, the itraconazole MICs were >8 μg/ml using the M38-A2 method due to trailing growth, whereas the corresponding itraconazole MICs obtained using the YeastOne method were all ≤0.25 μg/ml without trailing growth. These data suggest that the YeastOne method can be used as an alternative for azole susceptibility testing of Aspergillus species and for detecting the A. fumigatus TR34/L98H isolates but that this method fails to detect A. niger isolates exhibiting trailing growth with itraconazole. Additionally, for isolates with azole MICs that approach or that are at susceptibility breakpoints or with high amphotericin B MICs detected using the YeastOne method, further MIC confirmation using the reference CLSI method is needed.

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Characterization of Pre-Antibiotic Era Klebsiella pneumoniae Isolates with Respect to Antibiotic/Disinfectant Susceptibility and Virulence in Galleria mellonella

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05009-14 ◽

2015 ◽

Vol 59 (7) ◽

pp. 3966-3972 ◽

Cited By ~ 33

Author(s):

Matthew E. Wand ◽

Kate S. Baker ◽

Gabriel Benthall ◽

Hannah McGregor ◽

James W. I. McCowen ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Susceptibility Testing ◽

Galleria Mellonella ◽

Significant Proportion ◽

Minimal Bactericidal Concentration ◽

Bacterial Isolates ◽

Content Type ◽

The Mean ◽

Two Populations

ABSTRACTThe EGD Murray collection consists of approximately 500 clinical bacterial isolates, mainlyEnterobacteriaceae, isolated from around the world between 1917 and 1949. A number of these “Murray” isolates have subsequently been identified asKlebsiella pneumoniae. Antimicrobial susceptibility testing of these isolates showed that over 30% were resistant to penicillins due to the presence of diverseblaSHVβ-lactamase genes. Analysis of susceptibility to skin antiseptics and triclosan showed that while the Murray isolates displayed a range of MIC/minimal bactericidal concentration (MBC) values, the mean MIC value was lower than that for more modernK. pneumoniaeisolates tested. All Murray isolates contained the cation efflux genecepA, which is involved in disinfectant resistance, but those that were more susceptible to chlorhexidine were found to have a 9- or 18-bp insertion in this gene. Susceptibility to other disinfectants, e.g., H2O2, in the Murray isolates was comparable to that in modernK. pneumoniaeisolates. The Murray isolates were also less virulent inGalleriaand had a different complement of putative virulence factors than the modern isolates, with the exception of an isolate related to the modern lineage CC23. More of the modern isolates (41% compared to 8%) are classified as good/very good biofilm formers, but there was overlap in the two populations. This study demonstrated that a significant proportion of the MurrayKlebsiellaisolates were resistant to penicillins before their routine use. This collection of pre-antibiotic era isolates may provide significant insights into adaptation inK. pneumoniaein relation to biocide susceptibility.

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Three-dimensional fluoroscopy-guided percutaneous thoracolumbar pedicle screw placement

Journal of Neurosurgery Spine ◽

10.3171/spi.2003.99.3.0324 ◽

2003 ◽

Vol 99 (3) ◽

pp. 324-329 ◽

Cited By ~ 22

Author(s):

Langston T. Holly ◽

Kevin T. Foley

Keyword(s):

Pedicle Screw ◽

Three Dimensional ◽

Pedicle Screws ◽

Screw Placement ◽

Content Type ◽

Image Guided ◽

Spinal Navigation ◽

Mean Diameter ◽

The Mean ◽

Fine Print

✓ The authors sought to evaluate the feasibility and accuracy of three-dimensional (3D) fluoroscopic guidance for percutaneous placement of thoracic and lumbar pedicle screws in three cadaveric specimens. After attaching a percutaneous dynamic reference array to the surgical anatomy, an isocentric C-arm fluoroscope was used to obtain images of the region of interest. Light-emitting diodes attached to the C-arm unit were tracked using an electrooptical camera. The image data set was transferred to the image-guided workstation, which performed an automated registration. Using the workstation display, pedicle screw trajectories were planned. An image-guided drill guide was passed through a stab incision, and this was followed by sequential image-guided pedicle drilling, tapping, and screw placement. Pedicle screws of various diameters (range 4–6.5 mm) were placed in all pedicles greater than 4 mm in diameter. Postoperatively, thin-cut computerized tomography scans were obtained to determine the accuracy of screw placement. Eighty-nine (94.7%) of 94 percutaneous screws were placed completely within the cortical pedicle margins, including all 30 lumbar screws (100%) and 59 (92%) of 64 thoracic screws. The mean diameter of all thoracic pedicles was 6 mm (range 2.9–11 mm); the mean diameter of the five pedicles in which wall violations occurred was 4.6 mm (range 4.1–6.3 mm). Two of the violations were less than 2 mm beyond the cortex; the others were between 2 and 3 mm. Coupled with an image guidance system, 3D fluoroscopy allows highly accurate spinal navigation. Results of this study suggest that this technology will facilitate the application of minimally invasive techniques to the field of spine surgery.

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Antifungal Resistance to Fluconazole and Echinocandins Is Not Emerging in Yeast Isolates Causing Fungemia in a Spanish Tertiary Care Center

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02670-14 ◽

2014 ◽

Vol 58 (8) ◽

pp. 4565-4572 ◽

Cited By ~ 34

Author(s):

Laura Judith Marcos-Zambrano ◽

Pilar Escribano ◽

Carlos Sánchez ◽

Patricia Muñoz ◽

Emilio Bouza ◽

...

Keyword(s):

Susceptibility Testing ◽

Molecular Level ◽

Care Center ◽

Antifungal Susceptibility ◽

Tertiary Care ◽

Candida Guilliermondii ◽

Antifungal Resistance ◽

Its2 Region ◽

Content Type

ABSTRACTAccurate knowledge of fungemia epidemiology requires identification of strains to the molecular level. Various studies have shown that the rate of resistance to fluconazole ranges from 2.5% to 9% inCandidaspp. isolated from blood samples. However, trends in antifungal resistance have received little attention and have been studied only using CLSI M27-A3 methodology. We assessed the fungemia epidemiology in a large tertiary care institution in Madrid, Spain, by identifying isolates to the molecular level and performing antifungal susceptibility testing according to the updated breakpoints of European Committee for Antimicrobial Susceptibility Testing (EUCAST) definitive document (EDef) 7.2. We studied 613 isolates causing 598 episodes of fungemia in 544 patients admitted to our hospital (January 2007 to December 2013). Strains were identified after amplification and sequencing of the ITS1-5.8S-ITS2 region and further tested forin vitrosusceptibility to amphotericin B, fluconazole, posaconazole, voriconazole, micafungin, and anidulafungin. Resistance was defined using EUCAST species-specific breakpoints, and epidemiological cutoff values (ECOFFs) were applied as tentative breakpoints. Most episodes were caused byCandida albicans(46%),Candida parapsilosis(28.7%),Candida glabrata(9.8%), andCandida tropicalis(8%). Molecular identification enabled us to better detect cryptic species ofCandida guilliermondiiandC. parapsilosiscomplexes and episodes of polyfungal fungemia. The overall percentage of fluconazole-resistant isolates was 5%, although it was higher inC. glabrata(8.6%) and non-Candidayeast isolates (47.4%). The rate of resistance to echinocandins was 4.4% and was mainly due to the presence of intrinsically resistant non-Candidaspecies. Resistance mainly affected non-Candidayeasts. The rate of resistance to fluconazole and echinocandins did not change considerably during the study period.

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Comparing Etest and Broth Microdilution for Antifungal Susceptibility Testing of the Most-Relevant Pathogenic Molds

Journal of Clinical Microbiology ◽

10.1128/jcm.00925-15 ◽

2015 ◽

Vol 53 (10) ◽

pp. 3176-3181 ◽

Cited By ~ 28

Author(s):

Frédéric Lamoth ◽

Barbara D. Alexander

Keyword(s):

Amphotericin B ◽

Antifungal Therapy ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Multidrug Resistant ◽

Antifungal Susceptibility Testing ◽

Diffusion Method ◽

Broth Microdilution ◽

Content Type ◽

Broth Microdilution Method

Invasive mold infections are life-threatening diseases for which appropriate antifungal therapy is crucial. Their epidemiology is evolving, with the emergence of triazole-resistantAspergillusspp. and multidrug-resistant non-Aspergillusmolds. Despite the lack of interpretive criteria, antifungal susceptibility testing of molds may be useful in guiding antifungal therapy. The standard broth microdilution method (BMD) is demanding and requires expertise. We assessed the performance of a commercialized gradient diffusion method (Etest method) as an alternative to BMD. The MICs or minimal effective concentrations (MECs) of amphotericin B, voriconazole, posaconazole, caspofungin, and micafungin were assessed for 290 clinical isolates of the most representative pathogenic molds (154Aspergillusand 136 non-Aspergillusisolates) with the BMD and Etest methods. Essential agreements (EAs) within ±2 dilutions of ≥90% between the two methods were considered acceptable. EAs for amphotericin B and voriconazole were >90% for most potentially susceptible species. For posaconazole, the correlation was acceptable forMucoromycotinabut Etest MIC values were consistently lower forAspergillusspp. (EAs of <90%). Excellent EAs were found for echinocandins with highly susceptible (MECs of <0.015 μg/ml) or intrinsically resistant (MECs of >16 μg/ml) strains. However, MEC determinations lacked consistency between methods for strains exhibiting mid-range MECs for echinocandins. We concluded that the Etest method is an appropriate alternative to BMD for antifungal susceptibility testing of molds under specific circumstances, including testing with amphotericin B or triazoles for non-Aspergillusmolds (MucoromycotinaandFusariumspp.). Additional study of molecularly characterized triazole-resistantAspergillusisolates is required to confirm the ability of the Etest method to detect voriconazole and posaconazole resistance amongAspergillusspp.

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