Molecular Epidemiology and Microbiological Characteristics of Cryptococcus gattii VGII isolates from China

Cryptococcus gattii (C. gattii) is a fungal pathogen that once caused an outbreak of cryptococcosis on Vancouver Island, and had spread worldwide, while few data were available in China. In this study, seven clinical isolates of C. gattii VGII were collected from 19 hospitals, Multi-locus Sequence Typing (MLST) analysis and whole-genome sequencing (WGS) was performed, and combined with published data for phylogenetic analysis. In addition, in vitro antifungal susceptibility testing, phenotypic analysis, and in vivo virulence studies were performed, subsequently, histopathological analysis of lung tissue was performed. C.gattii VGII infected patients were mainly immunocompetent male, and most of them had symptoms of central nervous system (CNS) involvement. MLST results showed that isolates from china exhibited high genetic diversity, and sequence type (ST) 7 was the major ST among the isolates. Some clinical isolates showed a close phylogenetic relationship with strains from Australia and South America. All clinical isolates did not show resistance to antifungal drugs. In addition, there was no correlation between virulence factors (temperature, melanin production, and capsule size) and virulence while in vivo experiments showed significant differences in virulence among strains. Lung fungal burden and damage to lung tissue correlated with virulence, and degree of damage to lung tissue in mice may highlight differences in virulence. Our work seeks to provide useful data for molecular epidemiology, antifungal susceptibility, and virulence differences of C. gattii VGII in China.

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Susceptibility of the Candida haemulonii Complex to Echinocandins: Focus on Both Planktonic and Biofilm Life Styles and a Literature Review

Journal of Fungi ◽

10.3390/jof6040201 ◽

2020 ◽

Vol 6 (4) ◽

pp. 201

Author(s):

Lívia S. Ramos ◽

Laura N. Silva ◽

Marta H. Branquinha ◽

André L. S. Santos

Keyword(s):

Literature Review ◽

Therapeutic Potential ◽

Multidrug Resistant ◽

Antifungal Drugs ◽

Clinical Isolates ◽

Published Data ◽

Life Styles ◽

Fungal Isolates ◽

Candida Haemulonii ◽

Almost All

Candida haemulonii complex (C. haemulonii, C. duobushaemulonii and C. haemulonii var. vulnera) is well-known for its resistance profile to different available antifungal drugs. Although echinocandins are the most effective class of antifungal compounds against the C. haemulonii species complex, clinical isolates resistant to caspofungin, micafungin and anidulafungin have already been reported. In this work, we present a literature review regarding the effects of echinocandins on this emergent fungal complex. Published data has revealed that micafungin and anidulafungin were more effective than caspofungin against the species forming the C. haemulonii complex. Subsequently, we investigated the susceptibilities of both planktonic and biofilm forms of 12 Brazilian clinical isolates of the C. haemulonii complex towards caspofungin and micafungin (anidulafungin was unavailable). The planktonic cells of all the fungal isolates were susceptible to both of the test echinocandins. Interestingly, echinocandins caused a significant reduction in the biofilm metabolic activity (viability) of almost all fungal isolates (11/12, 91.7%). Generally, the biofilm biomasses were also affected (reduction range 20–60%) upon exposure to caspofungin and micafungin. This is the first report of the anti-biofilm action of echinocandins against the multidrug-resistant opportunistic pathogens comprising the C. haemulonii complex, and unveils the therapeutic potential of these compounds.

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Clinical and microbiological characteristics of Cryptococcus gattii isolated from China

10.21203/rs.2.21273/v1 ◽

2020 ◽

Author(s):

Liang Jin ◽

Jingrong Cao ◽

Xinying Xue ◽

Hua Wu ◽

Lifeng Wang ◽

...

Keyword(s):

Antifungal Agents ◽

Antifungal Susceptibility ◽

The United States ◽

Cryptococcus Gattii ◽

Clinical Isolates ◽

Strain Identification ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Significant Difference ◽

Tof Ms

Abstract Background: Infection, even outbreak, caused by Cryptococcus gattii (C. gattii ) has been reported in Canada and the United States, but there were sparsely-reported cases of C. gattii in China. Our interest in occurrence, clinical manifestation, laboratory identification and molecular characterization of Chinese C. gattii strains leads us to this research. Methods: A total of 254 clinical isolates primarily identified as Cryptococcus neoformans (C. neoformans ) were collected. VITEK 2 compact, canavanine glycine bromothymol blue (CGB) agar and Bruker Biotyper matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) were used for strain identification. Multi-locus sequence typing (MLST) was performed for genotyping. Antifungal susceptibility test was carried out with commercial kits of both ATB fungus 3 and Yeast one. Clinical information of patients was reviewed retrospectively. Label-free proteome technique was used to quantitatively analyze the differential proteins of C. gattii. Results: Out of 254 clinical isolates, we identified eight strains as C. gattii. MLST showed genotype VGI accounted for the most (6 / 8), the other two strains were genotype VGII（VGIIa and VGIIb respectively）with 3 specific spectra of molecular weight about 4342, 8686, 9611 Dalton by MALDI-TOF MS. The minimal inhibitory concentrations (MICs) of Fluconazole with Yeast one was 2～4 times higher than that with ATB fungus 3. Higher MICs of antifungal agents were exhibited against VGII strains than against VGI strains. C. gattii genotype VGII and VGI possessed 418 and 774 specific proteins respectively. Comparative proteome analysis showed that 180 proteins were highly expressed in C. gattii VGII and 329 proteins were highly expressed in C. gattii VGI. The enrichment of differentially expressed proteins between VGII and VGI was directed to Golgi complex.Conclusions: Infection by C. gattii in China might have been underestimated because of initial mis-identification. Genotype VGI was predominant but VGII was more resistant to antifungal agents. There was significant difference in protein expression profile between VGII and VGI C. gattii.

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Molecular epidemiology and phylogenetic analyses of environmental and clinical isolates of Cryptococcus gattii sensu lato in Taiwan

Mycoses ◽

10.1111/myc.13195 ◽

2020 ◽

Author(s):

Kuo‐Hsi Lin ◽

Yi‐Pei Lin ◽

Mao‐Wang Ho ◽

Yee‐Chun Chen ◽

Wen‐Hsin Chung

Keyword(s):

Molecular Epidemiology ◽

Phylogenetic Analyses ◽

Cryptococcus Gattii ◽

Clinical Isolates

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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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Molecular epidemiology, risk factors, species distribution, antifungal susceptibility and outcome of candidemia in the capital of Iran: a prospective study

10.21203/rs.3.rs-127871/v1 ◽

2020 ◽

Author(s):

Mohammad Kord ◽

Mohammadreza Salehi ◽

Seyed Jamal Hashemi ◽

Sassan Rezaie ◽

Ayda Maleki ◽

...

Keyword(s):

Risk Factors ◽

Molecular Epidemiology ◽

Species Distribution ◽

Clinical Symptoms ◽

Antifungal Susceptibility ◽

Underlying Disease ◽

Antifungal Drugs ◽

Teaching Hospitals ◽

A Prospective Study ◽

Underlying Diseases

Abstract Background Candidemia is a major cause of morbidity and mortality among patients receiving immunosuppressive therapy and those hospitalized with serious underlying diseases despite the commencement of antifungal therapy. We investigated the molecular epidemiology, clinical characteristics, comorbidity risk factors, species distribution, antifungal susceptibility profile, and outcome of candidemia to provide appropriate perspectives in Tehran, Iran. Methods A prospective observational study of all patients diagnosed with candidemia was performed at two referral teaching hospitals in Tehran. Demographic characteristics, underlying diseases, risk factors, clinical symptoms, and laboratory analyses were mined. Results One-hundred and fifty-two Candida isolates from 89 patients with candidemia were recovered. The overall crude mortality was 47.2%. The most common underlying disease was sepsis (48.3%) followed by malignancy (46.1%), renal failure/ dialysis (43.8%), and Hypertension (40.0%). C. albicans (43.8%) was the most frequent causative agent followed by C. glabrata (21.3%), C. parapsilosis complex (15.7%), C. tropicalis (11.2%), and C. lusitaniae (3.4%). Result of antifungal susceptibility test show that activity of all the four azole antifungal agents was low against non-albicans Candida species, especially C. tropicalis. Conclusion Increase in non-albicans Candida species with reduced susceptibility to antifungal drugs might be alarming in high-risk patients. Therefore, accurate knowledge of predisposing factors and epidemiological patterns in candidemia are effective steps for managing and decreasing the mortality rate in candidemia.

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In Vitro Antifungal Susceptibility Of Griseofulvin, Fluconazole, Itraconazole And Terbinafine Against Clinical Isolates Of Trichophyton Rubrum And Trichophyton Mentagrophytes

Asian Journal of Health Sciences ◽

10.15419/ajhs.v2i1.420 ◽

2014 ◽

Vol 2 (1) ◽

Author(s):

K R Reddy ◽

S Ram Reddy

Keyword(s):

Trichophyton Rubrum ◽

Clinical Laboratory ◽

Antifungal Susceptibility ◽

Trichophyton Mentagrophytes ◽

Drug Susceptibility ◽

Antifungal Drugs ◽

Clinical Isolates ◽

National Committee ◽

In Vitro Antifungal Susceptibility

Investigations on antifungal drug susceptibility were carried out on 90 clinical isolates of Trichophyton rubrum, and Trichophyton mentagrophytes with four antifungal drugs, namely griseofulvin, fluconazole, itraconazole and terbinafine as suggested by National Committee for Clinical Laboratory Standards (NCCLS) M27–A (1997) document by broth macrodilution method to standardize in vitro antifungal susceptibility testing and to find out the Minimum Inhibitory Concentration (MIC) of the drugs. In this study, terbinafine was found to be the most efficient drug for all isolates. Terbinafine had the lowest MIC range of 0.001 g/ml to 0.09 g/ml and MIC50 was low at 0.005 g/ml and MIC90 was also low at 0.04 g/ml against T.rubrum; and MIC range of 0.001μg/ml to 0.19μg/ml with a MIC50 of 0.01μg/ml and MIC90 at 0.09μg/ml against T.mentagrophytes. Itraconazole showed antifungal activity superior to that of fluconazole, with a MIC range of 0.04g/ml to 1.56g/ml, with MIC50 at 0.19μg/ml and MIC90 at 1.56g/ml against T.rubrum; and MIC range of 0.04μg/ml to 1.56μg/ml, with MIC50 at 0.19μg/ml and MIC90 at 0.78μg/ml against T.mentagrophytes. Griseofulvin appears to be still a potent drug for management of dermatophytoses. Griseofulvin had a MIC range of 0.15g/ml to 5.07 g/ml with MIC50 at1.26 g/ml and MIC90 at 2.53 g/ml against T.rubrum; and MIC range of 0.31μg/ml to 5.07μg/ml with MIC50 at 1.26μg/ml and MIC90 at 2.53μg/ml against T.mentagrophytes. Fluconazole showed a high MIC range of 0.19 g/ml to 50 g/ml and MIC50 was high at 1.56g/ml and MIC90 was also high at 12.5 g/ml against T.rubrum; and a high MIC range of 0.09μg/ml to 25.0μg/ml, with MIC50 at 1.56μg/ml and MIC90 at 12.5μg/ml towards T.mentagrophytes. The technique was found to be easy to perform and reliable with consistent results.

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In Vitro Antifungal Susceptibility and Molecular Characterization of Clinical Isolates of Fusarium verticillioides (F. moniliforme) and Fusarium thapsinum

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00176-08 ◽

2008 ◽

Vol 52 (6) ◽

pp. 2228-2231 ◽

Cited By ~ 28

Author(s):

Mónica Azor ◽

Josepa Gené ◽

Josep Cano ◽

Deanna A. Sutton ◽

Annette W. Fothergill ◽

...

Keyword(s):

Active Drug ◽

Fusarium Verticillioides ◽

Antifungal Susceptibility ◽

Antifungal Drugs ◽

Clinical Isolates ◽

Microdilution Method ◽

Fusarium Thapsinum ◽

In Vitro Antifungal Susceptibility

ABSTRACT A microdilution method was used to test 11 antifungal drugs against clinical isolates of Fusarium thapsinum and three different phylogenetic clades of Fusarium verticillioides that were characterized by sequencing a region of the β-tubulin gene. Terbinafine was the most-active drug against both species, followed by posaconazole against F. verticillioides.

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Species Identification andIn VitroAntifungal Susceptibility ofAspergillus terreusSpecies Complex Clinical Isolates from a French Multicenter Study

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02315-17 ◽

2018 ◽

Vol 62 (5) ◽

pp. e02315-17 ◽

Cited By ~ 4

Author(s):

S. Imbert ◽

A. C. Normand ◽

S. Ranque ◽

J. M. Costa ◽

J. Guitard ◽

...

Keyword(s):

Amphotericin B ◽

Antifungal Susceptibility ◽

Sensu Stricto ◽

Antifungal Drugs ◽

Clinical Isolates ◽

Clinical Samples ◽

Azole Resistance ◽

University Hospitals ◽

Content Type ◽

Interesting Alternative

ABSTRACTAspergillussectionTerreiis a species complex currently comprised of 14 cryptic species whose prevalence in clinical samples as well as antifungal susceptibility are poorly known. The aims of this study were to investigateA. Terreiclinical isolates at the species level and to perform antifungal susceptibility analyses by reference and commercial methods. Eighty-two clinicalA. Terreiisolates were collected from 8 French university hospitals. Molecular identification was performed by sequencing parts of beta-tubulin and calmodulin genes. MICs or minimum effective concentrations (MECs) were determined for 8 antifungal drugs using both EUCAST broth microdilution (BMD) methods and concentration gradient strips (CGS). Among the 79A. Terreiisolates,A. terreus stricto sensu(n= 61),A. citrinoterreus(n= 13),A. hortai(n= 3), andA. alabamensis(n= 2) were identified. All strains had MICs of ≥1 mg/liter for amphotericin B, except for two isolates (bothA. hortai) that had MICs of 0.25 mg/liter. FourA. terreusisolates were resistant to at least one azole drug, including one with pan-azole resistance, yet no mutation in theCYP51Agene was found. All strains had low MECs for the three echinocandins. The essential agreements (EAs) between BMD and CGS were >90%, except for those of amphotericin B (79.7%) and itraconazole (73.4%). Isolates belonging to theA. sectionTerreiidentified in clinical samples show wider species diversity beyond the knownA. terreus sensu stricto. Azole resistance inside the sectionTerreiis uncommon and is not related to CYP51A mutations here. Finally, CGS is an interesting alternative for routine antifungal susceptibility testing.

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

Frontiers in Microbiology ◽

10.3389/fmicb.2021.708280 ◽

2021 ◽

Vol 12 ◽

Author(s):

Najwa Al-Odaini ◽

Xiu-ying Li ◽

Bing-kun Li ◽

Xing-chun Chen ◽

Chun-yang Huang ◽

...

Keyword(s):

Cryptococcus Neoformans ◽

Amphotericin B ◽

Southern China ◽

Antifungal Susceptibility ◽

Sensu Stricto ◽

Cryptococcus Gattii ◽

Antifungal Drugs ◽

In Vitro Antifungal Susceptibility ◽

Susceptibility Profiles

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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