In vitro Antifungal Susceptibility Profiles of Cryptococcus neoformans var. grubii and Cryptococcus gattii Clinical Isolates in Guangxi, Southern China

This study analyzed the in vitro drug sensitivity of Cryptococcus spp. from Guangxi, Southern China. One hundred three strains of Cryptococcus were recovered from 86 patients; 14 were HIV positive and 72 were HIV negative. Ninety-two strains were identified as Cryptococcus neoformans var. grubii, while 11 strains were identified as Cryptococcus gattii (5 C. gattii sensu stricto and 6 Cryptococcus deuterogattii). The recovered strains were tested against commonly used antifungal drugs (fluconazole, amphotericin B, 5-fluorocytosine, itraconazole, and voriconazole) and to novel antifungal drugs (posaconazole and isavuconazole) using CLSI M27-A4 method. The results showed that all isolates were susceptible to most antifungal drugs, of which the minimum inhibitory concentration (MIC) ranges were as follows: 0.05–4 μg/ml for fluconazole, 0.25–1 μg/ml for amphotericin B; 0.0625–2 μg/ml for 5-fluorocytosine, 0.0625–0.25 μg/ml for itraconazole, 0.0078–0.25 μg/ml for voriconazole, 0.0313–0.5 μg/ml for posaconazole, 0.0020–0.125 μg/ml for isavuconazole for C. neoformans var. grubii isolates, and 1–16 μg/ml for fluconazole, 0.125–1 μg/ml for 5-fluorocytosine, 0.25–1 μg/ml for amphotericin B, 0.0625–0.25 μg/ml for itraconazole, 0.0156–0.125 μg/ml for voriconazole, 0.0156–0.25 μg/ml for posaconazole, and 0.0078–0.125 μg/ml for isavuconazole for C. gattii isolates. Furthermore, some C. neoformans var. grubii isolates were found to be susceptible-dose dependent to 5-fluorocytosine and itraconazole. In addition, a reduction in the potency of fluconazole against C. gattii is possible. We observed no statistical differences in susceptibility of C. neoformans var. grubii and C. gattii in the tested strains. Continuous observation of antifungal susceptibility of Cryptococcus isolates is recommended to monitor the emergence of resistant strains.

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In vitro antifungal susceptibility profiles and genotypes of 308 clinical and environmental isolates of Cryptococcus neoformans var. grubii and Cryptococcus gattii serotype B from north-western India

Journal of Medical Microbiology ◽

10.1099/jmm.0.029025-0 ◽

2011 ◽

Vol 60 (7) ◽

pp. 961-967 ◽

Cited By ~ 54

Author(s):

Anuradha Chowdhary ◽

Harbans Singh Randhawa ◽

Gandhi Sundar ◽

Shallu Kathuria ◽

Anupam Prakash ◽

...

Keyword(s):

Cryptococcus Neoformans ◽

Antifungal Susceptibility ◽

Cryptococcus Gattii ◽

Western India ◽

Environmental Isolates ◽

Serotype B ◽

In Vitro Antifungal Susceptibility ◽

Susceptibility Profiles ◽

North Western

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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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Comparison of MIC Test Strip and Sensititre YeastOne with the CLSI and EUCAST Broth Microdilution Reference Methods for In Vitro Antifungal Susceptibility Testing of Cryptococcus neoformans

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02261-19 ◽

2020 ◽

Vol 64 (4) ◽

Author(s):

Fatima Zohra Delma ◽

Abdullah M. S. Al-Hatmi ◽

Jochem B. Buil ◽

Hein van der Lee ◽

Marlou Tehupeiory-Kooreman ◽

...

Keyword(s):

Cryptococcus Neoformans ◽

Amphotericin B ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Test Strip ◽

Error Rates ◽

Broth Microdilution ◽

Content Type ◽

In Vitro Antifungal Susceptibility

ABSTRACT We compared MIC test strip (MTS) and Sensititre YeastOne (SYO) methods with EUCAST and CLSI methods for amphotericin B, 5-fluocytosine, fluconazole, voriconazole, and isavuconazole against 106 Cryptococcus neoformans isolates. The overall essential agreement between the EUCAST and CLSI methods was >72% and >94% at ±1 and ±2 dilutions, respectively. The essential agreements between SYO and EUCAST/CLSI for amphotericin B, 5-flucytosine, fluconazole, and voriconazole were >89/>93% and between MTS and EUCAST/CLSI were >57/>75%. Very major error rates were low for amphotericin B and fluconazole (<3%) and a bit higher for the other drugs (<8%).

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In Vitro Antifungal Susceptibility Profiles of 12 Antifungal Drugs against 55 Trichophyton schoenleinii Isolates from Tinea Capitis Favosa Patients in Iran, Turkey, and China

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01753-16 ◽

2016 ◽

Vol 61 (2) ◽

Cited By ~ 6

Author(s):

Shuwen Deng ◽

Saham Ansari ◽

Macit Ilkit ◽

Haleh Rafati ◽

Mohammad T. Hedayati ◽

...

Keyword(s):

Antifungal Agents ◽

Antifungal Susceptibility ◽

Antifungal Drugs ◽

Content Type ◽

Microdilution Method ◽

Broth Microdilution Method ◽

In Vitro Antifungal Susceptibility ◽

Trichophyton Schoenleinii ◽

Susceptibility Profiles

ABSTRACT Trichophyton schoenleinii is an anthropophilic dermatophyte mainly causing tinea favosa of the scalp in certain regions of the world, especially Africa and Asia. We investigated the in vitro susceptibilities of 55 T. schoenleinii isolates collected over the last 30 years from Iran, Turkey, and China to 12 antifungals using the CLSI broth microdilution method. Our results revealed that terbinafine and ketoconazole were the most potent antifungal agents among those tested, independently of the geographic regions where strains were isolated.

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Conventional therapy and new antifungal drugs against Malassezia infections

Medical Mycology ◽

10.1093/mmy/myaa087 ◽

2020 ◽

Author(s):

Wafa Rhimi ◽

Bart Theelen ◽

Teun Boekhout ◽

Chioma Inyang Aneke ◽

Domenico Otranto ◽

...

Keyword(s):

Antifungal Susceptibility ◽

Clinical Signs ◽

Bloodstream Infections ◽

Antifungal Drugs ◽

Malassezia Spp ◽

Susceptibility Tests ◽

In Vitro Antifungal Susceptibility ◽

Susceptibility Profiles

ABSTRACT Malassezia yeasts are commensal microorganisms occurring on the skin of humans and animals causing dermatological disorders or systemic infections in severely immunocompromised hosts. Despite attempts to control such yeast infections with topical and systemic antifungals, recurrence of clinical signs of skin infections as well as treatment failure in preventing or treating Malassezia furfur fungemia have been reported most likely due to wrong management of these infections (e.g., due to early termination of treatment) or due to the occurrence of resistant phenomena. Standardized methods for in vitro antifungal susceptibility tests of these yeasts are still lacking, thus resulting in variable susceptibility profiles to azoles among Malassezia spp. and a lack of clinical breakpoints. The inherent limitations to the current pharmacological treatments for Malassezia infections both in humans and animals, stimulated the interest of the scientific community to discover new, effective antifungal drugs or substances to treat these infections. In this review, data about the in vivo and in vitro antifungal activity of the most commonly employed drugs (i.e., azoles, polyenes, allylamines, and echinocandins) against Malassezia yeasts, with a focus on human bloodstream infections, are summarized and their clinical implications are discussed. In addition, the usefulness of alternative compounds is discussed.

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Antifungal susceptibility profiles of olorofim (formerly F901318), and currently available systemic antifungals against mold and yeast phases of Talaromyces marneffei

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00256-21 ◽

2021 ◽

Author(s):

Jing Zhang ◽

Hongfang Liu ◽

Liyan Xi ◽

Yun C. Chang ◽

Kyung J. Kwon-Chung ◽

...

Keyword(s):

Amphotericin B ◽

Antifungal Agent ◽

Southern China ◽

Antifungal Susceptibility ◽

Talaromyces Marneffei ◽

Mold And Yeast ◽

Susceptibility Profiles

In vitro antifungal susceptibility of 32 clinical and environmental Talaromyces marneffei isolates recovered from southern China was performed against olorofim and 7 other systemic antifungals including: amphotericin B, 5-flucytosine, posaconazole, voriconazole, caspofungin and terbinafine using the CLSI methodology. In comparison, olorofim was the most active antifungal agent against both mold and yeast phases of all tested Talaromyces marneffei isolates, exhibiting an MIC range, MIC50, and MIC90 of 0.0005-0.002 μg/ml, 0.0005 μg/ml, and 0.0005 μg/ml, respectively.

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Darunavir inhibits Cryptococcus neoformans/Cryptococcus gattii species complex growth and increases the susceptibility of biofilms to antifungal drugs

Journal of Medical Microbiology ◽

10.1099/jmm.0.001194 ◽

2020 ◽

Vol 69 (6) ◽

pp. 830-837

Author(s):

Raimunda Sâmia Nogueira Brilhante ◽

José Alexandre Telmos Silva ◽

Géssica dos Santos Araújo ◽

Vandbergue Santos Pereira ◽

Wilker Jose Perez Gotay ◽

...

Keyword(s):

Cryptococcus Neoformans ◽

Amphotericin B ◽

Metabolic Activity ◽

Biofilm Formation ◽

Species Complex ◽

Cryptococcus Gattii ◽

Antifungal Drugs ◽

Planktonic Cells ◽

Species Activity ◽

Checkerboard Assay

Introduction. Cryptococcus species are pathogens commonly associated with cases of meningoencephalitis in individuals who are immunosuppressed due to AIDS. Aim. The aim was to evaluate the effects of the antiretroviral darunavir alone or associated with fluconazole, 5-flucytosine and amphotericin B against planktonic cells and biofilms of Cryptococcus species. Methodology. Susceptibility testing of darunavir and the common antifungals against 12 members of the Cryptococcus neoformans/Cryptococcus gattii species complex was evaluated by broth microdilution. The interaction between darunavir and antifungals against planktonic cells was tested by a checkerboard assay. The effects of darunavir against biofilm metabolic activity and biomass were evaluated by the XTT reduction assay and crystal violet staining, respectively. Results. Darunavir combined with amphotericin B showed a synergistic interaction against planktonic cells. No antagonistic interaction was observed between darunavir and the antifungals used. All Cryptococcus species strains were strong biofilm producers. Darunavir alone reduced biofilm metabolic activity and biomass when added during and after biofilm formation (P<0.05). The combination of darunavir with antifungals caused a significant reduction in biofilm metabolic activity and biomass when compared to darunavir alone (P<0.05). Conclusion. Darunavir presents antifungal activity against planktonic cells of Cryptococcus species and synergism with amphotericin B. In addition, darunavir led to reduced biofilm formation and showed activity against mature biofilms of Cryptococcus species. Activity of the antifungals against mature biofilms was enhanced in the presence of darunavir.

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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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Relationship between the Antifungal Susceptibility Profile and the Production of Virulence-Related Hydrolytic Enzymes in Brazilian Clinical Strains ofCandida glabrata

Mediators of Inflammation ◽

10.1155/2017/8952878 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Maria Helena Galdino Figueiredo-Carvalho ◽

Lívia de Souza Ramos ◽

Leonardo Silva Barbedo ◽

Jean Carlos Almeida de Oliveira ◽

André Luis Souza dos Santos ◽

...

Keyword(s):

Amphotericin B ◽

Antifungal Susceptibility ◽

Hydrolytic Enzymes ◽

Antifungal Drug ◽

Clinical Strains ◽

Antifungal Drug Resistance ◽

Opportunistic Fungal Pathogen ◽

Esterase Production ◽

In Vitro Antifungal Susceptibility

Candida glabratais a facultative intracellular opportunistic fungal pathogen in human infections. Several virulence-associated attributes are involved in its pathogenesis, host-pathogen interactions, modulation of host immune defenses, and regulation of antifungal drug resistance. This study evaluated the in vitro antifungal susceptibility profile to five antifungal agents, the production of seven hydrolytic enzymes related to virulence, and the relationship between these phenotypes in 91 clinical strains ofC. glabrata. AllC. glabratastrains were susceptible to flucytosine. However, some of these strains showed resistance to amphotericin B (9.9%), fluconazole (15.4%), itraconazole (5.5%), or micafungin (15.4%). Overall,C. glabratastrains were good producers of catalase, aspartic protease, esterase, phytase, and hemolysin. However, caseinase and phospholipase in vitro activities were not detected. Statistically significant correlations were identified between micafungin minimum inhibitory concentration (MIC) and esterase production, between fluconazole and micafungin MIC and hemolytic activity, and between amphotericin B MIC and phytase production. These results contribute to clarify some of theC. glabratamechanisms of pathogenicity. Moreover, the association between some virulence attributes and the regulation of antifungal resistance encourage the development of new therapeutic strategies involving virulence mechanisms as potential targets for effective antifungal drug development for the treatment ofC. glabratainfections.

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