Species distribution and antifungal susceptibility profile of Candida isolates from bloodstream infections in Lima, Peru

Yeast identification and in vitro susceptibility testing provide helpful information for appropriate administration of antifungal treatments; however, few reports from the Latin American region have been published. The aim of this study was to identify the species present in isolates from bloodstream infections diagnosed in nine hospitals in Lima, Peru and to determine their in vitro susceptibility to four antifungal drugs. We tested and identified 153 isolates collected between October 2009 and August 2011 using standard methods. PCR and PCR-RFLP assays were performed to distinguish Candida albicans from Candida dubliniensis and to identify species of the Candida parapsilosis and Candida glabrata complexes. Antifungal susceptibility testing for fluconazole, anidulafungin and voriconazole was performed using the CSLI M27-A3 method, and amphotericin B susceptibility was determined using the Etest method. The most frequently isolated species were: C. albicans (61; 39.9 %), C. parapsilosis (43; 28.1 %), C. tropicalis (36; 23.5%) and C. glabrata (8; 5.2 %). The overall susceptibility rates were 98.0 %, 98.7 %, 98.0 % and 97.4 % for amphotericin B, fluconazole, voriconazole and anidulafungin, respectively. No isolate was resistant to more than one drug. These results showed that the rate of resistance to four antifungal drugs was low among Candida bloodstream isolates in Lima, Peru.

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In vitro susceptibility testing of four antifungal drugs against fungal isolates in onychomycosis

International Journal of Research in Medical Sciences ◽

10.18203/2320-6012.ijrms20183268 ◽

2018 ◽

Vol 6 (8) ◽

pp. 2774 ◽

Cited By ~ 3

Author(s):

Smita S. Kulkarni ◽

Jayshree B. Bhakre ◽

Ajit S. Damle

Keyword(s):

Amphotericin B ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Antifungal Susceptibility Testing ◽

Antifungal Drugs ◽

Etiological Agent ◽

Diffusion Method ◽

In Vitro Susceptibility ◽

Broth Macrodilution

Background: Onychomycosis is chronic fungal infection of fingernails and toenails. Variety of fungi cause onychomycosis. Due to importance of high prevalence rate of onychomycosis this study was conducted.Methods: In this study 100 patients suspected of onychomycosis were examined. Diagnosis of onychomycosis was based on the patient’s history, physical examination, microscopy and culture of nail specimens.Results: Direct microscopy of the nail clippings in 20% KOH solution was positive in 61% and culture was positive in 54% cases. The common etiological agent was dermatophytes (79.6% cases) followed by non dermatophyte moulds (11.1% cases) and yeasts (9.2% cases). Amongst dermatophytes, T. rubrum was found to be commonest etiological agent (57.6%) followed by T. mentagrophytes. We had performed the in vitro antifungal susceptibility testing of isolated fungal species against Amphotericin B, Fluconazole, Itraconazole and Terbinafine according to standard guidelines recommended by the CLSI. Antifungal susceptibility testing of dermatophytes and non-dermatophyte moulds was performed by broth macrodilution method. For Candida species we used broth macrodilution method as well as disk diffusion method. All three Candida albicans isolates were sensitive to amphotericin B, fluconazole and itraconazole. Two strains of Candida krusei were sensitive to amphotericin B and resistant to fluconazole and itraconazole. Two isolates of T. rubrum had MIC >64µg/ml and one T. Mentagrophytes isolate had MIC 32µg/ml for fluconazole. Among non dermatophyte moulds, Aspergillus niger and one isolate of Fusarium oxysporum showed high MICs against fluconazole.Conclusions: Terbinafine exhibited the lowest MICs among all the tested antifungal drugs.

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Use of spectrophotometric reading for in vitro antifungal susceptibility testing ofAspergillusspp.

Canadian Journal of Microbiology ◽

10.1139/w99-075 ◽

1999 ◽

Vol 45 (10) ◽

pp. 871-874 ◽

Cited By ~ 7

Author(s):

Eric Dannaoui ◽

Florence Persat ◽

Marie-France Monier ◽

Elisabeth Borel ◽

Marie-Antoinette Piens ◽

...

Keyword(s):

Amphotericin B ◽

Susceptibility Testing ◽

Clinical Laboratory ◽

Antifungal Susceptibility ◽

Reference Method ◽

Antifungal Susceptibility Testing ◽

Aspergillus Species ◽

National Committee ◽

Broth Microdilution Method

A comparative study of visual and spectrophotometric MIC endpoint determinations for antifungal susceptibility testing of Aspergillus species was performed. A broth microdilution method adapted from the National Committee for Clinical Laboratory Standards (NCCLS) was used for susceptibility testing of 180 clinical isolates of Aspergillus species against amphotericin B and itraconazole. MICs were determined visually and spectrophotometrically at 490 nm after 24, 48, and 72h of incubation, and MIC pairs were compared. The agreement between the two methods was 99% for amphotericin B and ranged from 95 to 98% for itraconazole. It is concluded that spectrophotometric MIC endpoint determination is a valuable alternative to the visual reference method for susceptibility testing of Aspergillus species.Key words: antifungal, susceptibility testing, Aspergillus, spectrophotometric reading.

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Recent Exposure to Caspofungin or Fluconazole Influences the Epidemiology of Candidemia: a Prospective Multicenter Study Involving 2,441 Patients

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01128-10 ◽

2010 ◽

Vol 55 (2) ◽

pp. 532-538 ◽

Cited By ~ 223

Author(s):

Olivier Lortholary ◽

Marie Desnos-Ollivier ◽

Karine Sitbon ◽

Arnaud Fontanet ◽

Stéphane Bretagne ◽

...

Keyword(s):

Intensive Care Unit ◽

Odds Ratio ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Bloodstream Infections ◽

Antifungal Drugs ◽

Surveillance Program ◽

Prospective Multicenter Study ◽

Recent Exposure ◽

Adults And Children

ABSTRACTA prospective multicenter surveillance program on yeast bloodstream infections was implemented in the Paris, France, area without restrictions on ward of hospitalization (intensive care unit, hematology, and surgery) or age (adults and children). The present analysis concerns 2,618 isolates collected over 7 years from 2,441 patients. Centralized species identification and antifungal susceptibility testing using the EUCAST methodology were performed. Almost 10% (232/2,441) of the patients had recently (≤30 days) been treated with antifungal drugs. We analyzed the effect of recent exposure to fluconazole (n= 159) or caspofungin (n= 61) on the proportions of the five majorCandidaspecies. For both drugs, preexposure was associated with a decreased prevalence ofCandida albicansin favor of less drug-susceptible species (C. glabrataandC. kruseifor the former andC. parapsilosisand, to a lesser extent,C. glabrataandC. kruseifor the latter;P= 0.001). In the multivariate analysis, the risk of being infected with an isolate with decreased susceptibility to fluconazole was independently associated with an age of ≥15 years (odds ratio [OR] = 2.45; 95% confidence interval [CI] = 1.39 to 4.31;P= 0.002) and with recent exposure to fluconazole (OR = 2.17; 95% CI = 1.51 to 3.13;P< 0.001), while the risk of being infected with an isolate with decreased susceptibility to caspofungin was independently associated with an age <15 years (OR = 2.53; 95% CI = 1.43 to 4.48;P= 0.001) and with recent exposure to caspofungin (OR = 4.79; 95% CI = 2.47 to 9.28;P< 0.001). These findings could influence future recommendations for the management of candidemia.

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In vitro activity of olorofim against clinical isolates of Scedosporium species and Lomentospora prolificans using EUCAST and CLSI methodologies

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkaa351 ◽

2020 ◽

Vol 75 (12) ◽

pp. 3582-3585

Author(s):

Olga Rivero-Menendez ◽

Manuel Cuenca-Estrella ◽

Ana Alastruey-Izquierdo

Keyword(s):

Amphotericin B ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Vitro Activity ◽

Clinical Isolates ◽

Scedosporium Apiospermum ◽

In Vitro Activity ◽

Scedosporium Dehoogii ◽

Scedosporium Species

Abstract Objectives To evaluate the in vitro activity of olorofim, a new broad-spectrum antifungal with a novel mechanism of action, against a collection of 123 Spanish clinical isolates belonging to five Scedosporium species and Lomentospora prolificans. Methods The activity of olorofim against Scedosporium apiospermum (n = 30), Scedosporium boydii (n = 30), Scedosporium ellipsoideum (n = 10), Scedosporium aurantiacum (n = 20), Scedosporium dehoogii (n = 3) and Lomentospora prolificans (n = 30) was compared with that of amphotericin B, voriconazole, isavuconazole and micafungin by performing EUCAST and CLSI reference methods for antifungal susceptibility testing. Results Amphotericin B and isavuconazole showed MICs ≥2 mg/L for all the species evaluated and voriconazole was moderately active (GM, MIC50 and MIC90 values ≤2 mg/L) against all of them except L. prolificans. Micafungin was effective against S. apiospermum complex strains, but exhibited elevated MECs for S. dehoogii and S. aurantiacum. Olorofim showed low MICs for all the Scedosporium strains tested (GM values were lower than 0.130 and 0.339 by the EUCAST method and the CLSI method, respectively, for all of the species), including those belonging to the MDR species L. prolificans, for which GM values were 0.115 and 0.225 mg/L by the EUCAST method and the CLSI method, respectively, while the GMs for the rest of the antifungals evaluated were higher than 3.732 mg/L using both methodologies. Conclusions Olorofim displayed promising in vitro activity against the Scedosporium and L. prolificans strains tested, some of which have reduced susceptibility to the antifungals that are currently in use.

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In Vitro Azole and Amphotericin B Susceptibilities of Malassezia furfur from Bloodstream Infections Using E-Test and CLSI Broth Microdilution Methods

Antibiotics ◽

10.3390/antibiotics9060361 ◽

2020 ◽

Vol 9 (6) ◽

pp. 361 ◽

Cited By ~ 2

Author(s):

Wafa Rhimi ◽

Chioma Inyang Aneke ◽

Adriana Mosca ◽

Domenico Otranto ◽

Claudia Cafarchia

Keyword(s):

Amphotericin B ◽

Reading Time ◽

Antifungal Susceptibility ◽

Bloodstream Infections ◽

Hospitalized Patients ◽

Malassezia Furfur ◽

Broth Microdilution ◽

Test Procedures ◽

The Media

The number of reports of Malassezia furfur bloodstream infections is constantly increasing and there is a need for more simple antifungal susceptibility methods for their management. In this study, a total of 39 M. furfur isolates collected from hospitalized patients with fungemia were screened for antifungal susceptibility to azole and amphotericin B (AmB) using Clinical and Laboratory Standards Institute broth microdilution (CLSI BMD) and E-test in Sabouraud dextrose agar + 1% Tween80 (SDAt) and mDixon agar (DIX). Essential agreement (EA) and discrepancies between the two methods were evaluated after 48 h and 72 h reading times. Itraconazole (ITZ) and posaconazole (POS) displayed the lowest MIC values whereas fluconazole (FLZ) and AmB the highest, regardless of the methods and the reading time. The EA between BMD was >95% for FLZ and voriconazole (VOR) regardless of the media in the E-tests and reading time. The EA between BMD with E-test for AmB was >97% only when E-test in SDAt was used. The EA between BMD and E-test for ITZ and POS varied according to the media in E-test procedures and the reading time and was higher than 66.6% (POS) or 72% (ITZ) only when SABt was used. Substantial discrepancies for ITZ and POS were >5.1% regardless of the media and the reading time. This study suggests that the E-test in SABt represents an alternative method to CLSI BMD to evaluate the susceptibility of M. furfur to FLZ, VOR and AmB and not for ITZ and POS.

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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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Etest Cannot Be Recommended forIn VitroSusceptibility Testing of Mucorales

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00004-15 ◽

2015 ◽

Vol 59 (6) ◽

pp. 3663-3665 ◽

Cited By ~ 20

Author(s):

Rita Caramalho ◽

Elisabeth Maurer ◽

Ulrike Binder ◽

Ricardo Araújo ◽

Somayeh Dolatabadi ◽

...

Keyword(s):

Amphotericin B ◽

Antimicrobial Susceptibility ◽

Active Drug ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Antifungal Susceptibility Testing ◽

Broth Microdilution ◽

European Committee ◽

Susceptibility Patterns

ABSTRACTAmphotericin B and posaconazole susceptibility patterns were determined for the most prevalent Mucorales, following EUCAST (European Committee on Antimicrobial Susceptibility Testing) broth microdilution guidelines. In parallel, Etest was performed and evaluated against EUCAST. The overall agreement of MICs gained with Etest and EUCAST was 75.1%; therefore, Etest cannot be recommended for antifungal susceptibility testing of Mucorales. Amphotericin B was the most active drug against Mucorales speciesin vitro, while the activities of posaconazole were more restricted.

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Comparative antifungal susceptibility analyses of Cryptococcus neoformans VNI and Cryptococcus gattii VGII from the Brazilian Amazon Region by the Etest, Vitek 2, and the Clinical and Laboratory Standards Institute broth microdilution methods

Medical Mycology ◽

10.1093/mmy/myy150 ◽

2019 ◽

Vol 57 (7) ◽

pp. 864-873 ◽

Cited By ~ 3

Author(s):

Marília Martins Nishikawa ◽

Rodrigo Almeida-Paes ◽

Fabio Brito-Santos ◽

Carlos Roberto Nascimento ◽

Miguel Madi Fialho ◽

...

Keyword(s):

Amphotericin B ◽

Antifungal Susceptibility ◽

Amazon Region ◽

Antifungal Drugs ◽

Epidemiological Surveillance ◽

Broth Microdilution ◽

Wild Type ◽

Brazilian Amazon Region ◽

Vitek 2

AbstractEarly diagnosis, efficient clinical support, and proper antifungal therapy are essential to reduce death and sequels caused by cryptococcosis. The emergence of resistance to the antifungal drugs commonly used for cryptococcosis treatment is an important issue of concern. Thus, the in vitro antifungal susceptibility of clinical strains from northern Brazil, including C. neoformans VNI (n = 62) and C. gattii VGII (n = 37), to amphotericin B (AMB), 5-flucytosine, fluconazole, voriconazole, and itraconazole was evaluated using the Etest and Vitek 2 systems and the standardized broth microdilution (CLSI-BMD) methodology. According to the CLSI-BMD, the most active in vitro azole was voriconazole (C. neoformans VNI modal MIC of 0.06 μg/ml and C. gattii VGII modal MIC of 0.25 μg/ml), and fluconazole was the least active (modal MIC of 4 μg/ml for both fungi). Modal MICs for amphotericin B were 1 μg/ml for both fungi. In general, good essential agreement (EA) values were observed between the methods. However, AMB presented the lowest EA between CLSI-BMD and Etest for C. neoformans VNI and C. gattii VGII (1.6% and 2.56%, respectively, P < .05 for both). Considering the proposed Cryptococcus spp. epidemiological cutoff values, more than 97% of the studied isolates were categorized as wild-type for the azoles. However, the high frequency of C. neoformans VNI isolates in the population described here that displayed non-wild-type susceptibility to AMB is noteworthy. Epidemiological surveillance of the antifungal resistance of cryptococcal strains is relevant due to the potential burden and the high lethality of cryptococcal meningitis in the Amazon region.

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Genetic Diversity and In Vitro Antifungal Susceptibility of 200 Clinical and Environmental Aspergillus flavus Isolates

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00004-17 ◽

2017 ◽

Vol 61 (5) ◽

Cited By ~ 15

Author(s):

Mojtaba Taghizadeh-Armaki ◽

Mohammad Taghi Hedayati ◽

Saham Ansari ◽

Saeed Mahdavi Omran ◽

Sasan Saber ◽

...

Keyword(s):

Amphotericin B ◽

Aspergillus Flavus ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Content Type ◽

Microdilution Method ◽

Microsatellite Genotype ◽

Broth Microdilution Method ◽

In Vitro Antifungal Susceptibility

ABSTRACT Aspergillus flavus has been frequently reported as the leading cause of invasive aspergillosis in certain tropical and subtropical countries. Two hundred A. flavus strains originating from clinical and environmental sources and collected between 2008 and 2015 were phylogenetically identified at the species level by analyzing partial β-tubulin and calmodulin genes. In vitro antifungal susceptibility testing was performed against antifungals using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) broth microdilution method. In addition, genotyping was performed using a short-tandem-repeat (STR) assay of a panel of six microsatellite markers (A. flavus 2A, 2B, 2C, 3A, 3B, and 3C), in order to determine the genetic variation and the potential relationship between clinical and environmental isolates. The geometric means of the minimum inhibitory concentrations/minimum effective concentrations (MICs/MECs) of the antifungals across all isolates were (in increasing order): posaconazole, 0.13 mg/liter; anidulafungin, 0.16 mg/liter; itraconazole, 0.29 mg/liter; caspofungin, 0.42 mg/liter; voriconazole, 0.64 mg/liter; isavuconazole, 1.10 mg/liter; amphotericin B, 3.35 mg/liter; and flucytosine, 62.97 mg/liter. All of the clinical isolates were genetically different. However, an identical microsatellite genotype was found between a clinical isolate and two environmental strains. In conclusion, posaconazole and anidulafungin showed the greatest in vitro activity among systemic azoles and echinocandins, respectively. However, the majority of the A. flavus isolates showed reduced susceptibility to amphotericin B. Antifungal susceptibility of A. flavus was not linked with the clinical or environmental source of isolation. Microsatellite genotyping may suggest an association between clinical and environmental strains, although this requires further investigation.

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Molecular typing and in vitro antifungal susceptibility of Cryptococcus spp from patients in Midwest Brazil

The Journal of Infection in Developing Countries ◽

10.3855/jidc.4446 ◽

2014 ◽

Vol 8 (08) ◽

pp. 1037-1043 ◽

Cited By ~ 13

Author(s):

Olivia Cometti Favalessa ◽

Daphine Ariadne Jesus De Paula ◽

Valeria Dutra ◽

Luciano Nakazato ◽

Tomoko Tadano ◽

...

Keyword(s):

Amphotericin B ◽

Fungal Infections ◽

Antifungal Susceptibility ◽

Cryptococcus Gattii ◽

Antifungal Drugs ◽

Northeastern Brazil ◽

In Vitro Susceptibility ◽

Mato Grosso ◽

Hiv Negative

Introduction: Cryptococcosis is a systemic fungal infection that affects humans and animals, mainly due to Cryptococcus neoformans and Cryptococcus gattii. Following the epidemic of acquired immunodeficiency syndrome (AIDS), fungal infections by C. neoformans have become more common among immunocompromised patients. Cryptococcus gattii has primarily been isolated as a primary pathogen in healthy hosts and occurs endemically in northern and northeastern Brazil. We to perform genotypic characterization and determine the in vitro susceptibility profile to antifungal drugs of the Cryptococcus species complex isolated from HIV-positive and HIV-negative patients attended at university hospitals in Cuiabá, MT, in the Midwestern region of Brazil. Methodology: Micromorphological features, chemotyping with canavanine-glycine-bromothymol blue (CGB) agar and genotyping by URA5-RFLP were used to identify the species. The antifungal drugs tested were amphotericin B, fluconazole, flucytosine, itraconazole and voriconazole. Minimum inhibitory concentrations (MICs) were determined according to the CLSI methodology M27-A3. Results: Analysis of samples yelded C. neoformans AFLP1/VNI (17/27, 63.0%) and C. gattii AFLP6/VGII (10/27, 37.0%). The MICs ranges for the antifungal drugs were: amphotericin B (0.5-1 mg/L), fluconazole (1-16 mg/L), flucytosine (1-16 mg/L), itraconazole (0.25-0.12 mg/L) and voriconazole (0.06-0.5 mg/L). Isolates of C. neoformans AFLP1/VNI were predominant in patients with HIV/AIDS, and C. gattii VGII in HIV-negative patients. The genotypes identified were susceptible to the antifungal drugs tested. Conclusion: It is worth emphasizing that AFLP6/VGII is a predominant genotype affecting HIV-negative individuals in Cuiabá. These findings serve as a guide concerning the molecular epidemiology of C. neoformans and C. gattii in the State of Mato Grosso.

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