Comparative evaluation of six chromogenic media for presumptive yeast identification

2017 ◽  
Vol 70 (12) ◽  
pp. 1074-1078 ◽  
Author(s):  
Alessandra Vecchione ◽  
Walter Florio ◽  
Francesco Celandroni ◽  
Simona Barnini ◽  
Antonella Lupetti ◽  
...  

AimsThe present study was undertaken to evaluate the discrimination ability of six chromogenic media in presumptive yeast identification.MethodsWe analysed 108 clinical isolates and reference strains belonging to eight different species: Candida albicans,Candida dubliniensis, Candida tropicalis, Candida krusei, Candida glabrata, Candida parapsilosis,Candida lusitaniae and Trichosporon mucoides.ResultsC. albicans, C. tropicalis and C. krusei could be distinguished from one another in all the tested chromogenic media, as predicted by the manufacturers. In addition, C. albicans could be distinguished from C. dubliniensis on BBL CHROMagar Candida, Kima CHROMagar Candida and Brilliance Candida, and C. parapsilosis could be identified on CHROMATIC Candida agar, CHROMOGENIC Candida agar, and Brilliance Candida agar.ConclusionsBrilliance Candida provided the widest discrimination ability, being able to discriminate five out of the seven Candida species tested. Interestingly, C. tropicalis and C. krusei could be already distinguished from each other after 24 hours of incubation.

2010 ◽  
Vol 43 (6) ◽  
pp. 673-677 ◽  
Author(s):  
Olivia Cometti Favalessa ◽  
Marilena dos Anjos Martins ◽  
Rosane Christine Hahn

INTRODUÇÃO: A candidíase é uma das infecções fúngicas mais frequentes entre os pacientes infectados pelo vírus da imunodeficiência humana. O presente estudo objetivou a caracterização das leveduras do gênero Candida de distintas amostras clínicas, provenientes de pacientes HIV - positivos, assim como a determinação do perfil de suscetibilidade in vitro a cinco drogas antifúngicas. MÉTODOS: A caracterização dos isolados de Candida sp foi realizada através da metodologia clássica, testes bioquímicos (zimograma e auxanograma) e morfológicos (prova do tubo germinativo e microcultivo em lâmina). Também, foram realizadas a técnica genotípica (PCR) e identificação pelo método comercial API 20C AUX (BioMeriéux). Para a determinação do perfil de suscetibilidade in vitro, foram utilizadas cinco drogas antifúngicas (cetoconazol, fluconazol, itraconazol, voriconazol e anfotericina B), através do método comercialmente disponível - Etest. RESULTADOS: Foram identificados 105 isolados de leveduras do gênero Candida provenientes de 102 pacientes infectados pelo vírus HIV. Destes, foram caracterizadas 82 (78,1%) Candida albicans, 8 (7,6%) Candida parapsilosis, 8 (7,6%) Candida tropicalis, 4 (3,8%) Candida krusei, 2 (1,9%) Candida glabrata e 1 (1%) Candida guilliermondii. CONCLUSÕES: Considerando o perfil geral de sensibilidade, 60% dos isolados foram suscetíveis a todos os antifúngicos testados, porém as espécies C. tropicalis e C. krusei demonstraram uma tendência a valores mais elevados de CIMs para os azóis do que os encontrados paraC. albicans, sugerindo resistência.


Revista Fitos ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 22-31
Author(s):  
Luiz Francisley de Paiva ◽  
Sabrina de Alvarenga Domingues

Candida sp. é um gênero de levedura que faz parte da microbiota do corpo humano e de animais. É considerado o principal grupo de fungos patógenos oportunistas. O uso de plantas medicinais é empregado cada vez mais nas diversas áreas. A planta Cymbopogon citratus (DC). Stapf é popularmente conhecida no Brasil por Capim-cheiroso, Capim-cidreira, Capim-santo, Capim-limão, Capim-cidró, Capim-cidrão. Este estudo teve como objetivo avaliar a atividade antifúngica do óleo essencial de Cymbopogon citratus frente a leveduras do gênero Candida sp.. O óleo essencial foi obtido por hidrodestilação das folhas pelo método do arraste a vapor. A atividade antifúngica foi verificada pelas técnicas de disco-difusão, concentração inibitória mínima e concentração letal mínima. Foram utilizadas as cepas padrão ATCC de Candida albicans, Candida dubliniensis, Candida tropicalis, Candida glabrata, Candida Krusei, Candida parapsilosis e Candida utilis. O óleo essencial apresentou atividade antifúngica frente a todas as espécies. A faixa de inibição varia de 0,281 µg/mL a 1,125 µg/mL e concentração letal varia de 0,562 µg/mL a 1,125 µg/mL. Esses achados contribuem para um futuro emprego da planta C. citratus como fitoterápico em tratamento preventivo ou alternativo contra infecções fúngicas.


Author(s):  
Sarah Raquel De Annunzio ◽  
Filipe Silveira Fusco ◽  
Carolina Santezi Santezi ◽  
Bárbara Donadon Reina ◽  
Lívia Nordi Dovigo

Objective: to evaluate the concordance of different plating methods for quantification of Candida species colonies. Method: standardized suspensions of reference strains (Candida albicans, Candida glabrata, Candida tropicalis and Candida krusei) were submitted to serial dilution and plating according to methods of track-dilution (TDM), drop plate (DPM) and the conventional spread plate (SPM). Data were submitted to construction of Bland–Altman diagrams, Intraclass Correlation Coefficient (ICC) and ANOVA (⍺=5%). Results: adequate concordance between the methods (CCI >0.71) was observed, and the execution of DPM was the fastest (p<0.001). However, DPM and TDM appear to result in greater values compared to SPM, especially for C. tropicalis and C. krusei. Conclusion: C. albicans and C. glabrata can be plated with DPM and TDM, but the use of these methods for C. krusei and C. tropicalis may result in count variation.


Author(s):  
Joachim Ohiakwu Ezeadila ◽  
Ikechukwu Okoli ◽  
Christie Amaechi Oyeka

There is an increase in non-albicans Candida (NAC) vulvovaginal candidiasis which is attributed to overuse of antifungal therapy and this has led to antifungal resistance. This study was aimed at determining the antifungal resistance pattern of some clinical isolates of Candida species. Eighty-eight (88) isolates were used which included Candida tropicalis (34), Candida Parapsilosis (21), Candida albicans (20), Candida krusei (7) and Candida glabrata (6). The drugs used were Fluconazole (25µg), Ketoconazole (10µg), Voriconazole (1µg), Nystatin (100Units), Amphotericin B (20µg), Flucytosine (1µg), Clotrimazole (10µg) and Itraconazole (50µg). The susceptibility testing was carried out using the M44-A standard method for yeast disk diffusion testing. Results showed that the percentages of Candida species resistant to Fluconazole, Ketoconazole, Voriconazole, Amphotericin B, Flucytosine, Clotrimazole and Itraconazole and Nystatin were 52.3%, 61.9%, 35.2%, 19.3%, 86.4%, 34.1%,  45.5% and 44.3%,  with inhibition zone diameters ≤14mm, ≤20mm, ≤13mm, <10mm, ≤11mm, ≤11mm, ≤13mm and no inhibition zone diameter respectively. Candida krusei was the most resistant species with 100% resistance to each of Fluconazole, Ketoconazole and Flucytosine. Candida tropicalis was the species with the highest susceptibility (79.4%) to Amphotericin B followed by Candida parapsilosis with inhibition zone diameters ≥15mm. While Candida glabrata showed 100% resistance to each of Flucytosine and Itraconazole, Candida albicans showed 100% resistance to Flucytosine only. Candida glabrata was the only Candida species with 0% resistance to Amphotericin B. The drug to which most of the Candida species were susceptible was Amphotericin B followed by Voriconazole while Flucytosine was the drug with the highest resistance followed by Ketoconazole and Fluconazole. The highest number of susceptible-dose dependent Candida isolates was observed with Ketoconazole (25%), followed by Clotrimazole and Itraconazole, each recording 23.9%. Based on the findings of the present study, Voriconazole is recommended for vaginal candidiasis especially in the study area and also especially for infections caused by Fluconazole-resistant Candida species. This suggests that routine sensitivity testing is pertinent to guiding the choice of antifungal therapy. Thus, indiscriminate use of antifungal drugs should be avoided to reduce the development and spread of resistance.


2008 ◽  
Vol 41 (1) ◽  
pp. 23-28 ◽  
Author(s):  
João Cesar Beenke França ◽  
Clea Elisa Lopes Ribeiro ◽  
Flávio de Queiroz-Telles

São apresentados os resultados de estudo transversal e observacional sobre candidemia realizado no Hospital de Clínicas da Universidade Federal do Paraná. No período de janeiro de 2001 a dezembro de 2004, foram analisados 100 episódios de candidemia. A incidência foi de 1,27 por 1.000 internações, sendo Candida spp o oitavo agente mais isolado nas infecções da corrente sanguínea. A idade variou de 5 dias a 89 anos com uma média de 32 anos, 60% dos casos ocorreram em adultos (66% > 50 anos) e 40% em crianças (52% < 1 ano). Cinqüenta e nove pacientes estavam internados em enfermarias e 41 em unidade de terapia intensiva. Candida albicans foi a espécie mais (59%) freqüente, seguida por Candida tropicalis (15%), Candida parapsilosis (9%). As condições associadas mais (97%) freqüentes foram uso de antibióticos, cateter venoso central (77%), bloqueador H2 (57%), nutrição parenteral total (49%) internamento em unidade de terapia intensiva (41%). Dos 51 isolados testados, 3 de Candida glabrata apresentaram suscetibilidade dose-dependente ao fluconazol e eram resistentes ao itraconazol. Uma amostra de Candida krusei apresentou suscetibilidade dose-dependente ao fluconazol, e uma de Candida pelliculosa suscetibilidade dose-dependente ao itraconazol. Na população de estudo, 68% receberam tratamento antifúngico, no entanto a mortalidade foi de 56%.


2001 ◽  
Vol 45 (6) ◽  
pp. 1905-1907 ◽  
Author(s):  
Manuel Cuenca-Estrella ◽  
Emilia Mellado ◽  
Teresa M. Dı́az-Guerra ◽  
Araceli Monzón ◽  
Juan L. Rodrı́guez-Tudela

ABSTRACT The in vitro activity of the azasordarin GW 471558 was compared with those of amphotericin B, flucytosine, itraconazole, and ketoconazole against 177 clinical isolates of Candidaspp. GW 471558 showed potent activity against Candida albicans, Candida glabrata, and Candida tropicalis, even against isolates with decreased susceptibility to azoles. Candida krusei, Candida parapsilosis, Candida lusitaniae, and Candida guilliermondii are resistant to GW 471558 in vitro (MICs, >128 μg/ml).


2015 ◽  
Vol 21 (5-6) ◽  
pp. 255-266
Author(s):  
Carmen A. Vides-Peña ◽  
Nalleth D. Bolaño-Ardila ◽  
Máryuris V. Vides-Peña ◽  
Susana B. Córdoba

Introducción: la candidemia es una enfermedad grave, con elevada morbi-mortalidad y cuyo tratamiento no siempre conduce a la cura. La distribución de especies de Candida y la sensibilidad antifúngica varía según el área geográfica, incluso entre centros de salud de una misma región. Objetivo: establecer la distribución de especies de Candida y su sensibilidad in vitro frente a diferentes antifúngicos. Materiales y métodos: se realizó un estudio descriptivo, prospectivo y transversal entre noviembre de 2013 y mayo de 2014 de casos de candidemias en una institución de salud de Valledupar, Colombia. Las Concentraciones Inhibitorias Mínimas (CIM) se determinaron según el protocolo estándar M27-A3-S4. Resultados: Se estudiaron 40 aislados clínicos de Candida spp. obtenidos de sangre (97,5%) y médula ósea (2,5%). Del total, 15 (37,5%) fueron caracterizados como Candida tropicalis, 13 (32,5%) del Complejo Candida albicans, cinco (12,5%) del Complejo Candida glabrata, tres (7,5%) como Candida guilliermondii, tres (7,5%) del Complejo Candida parapsilosis y uno (2,5%) como Candida krusei. No se observó resistencia a la anfotericina B ni al voriconazol en ninguno de los aislados, pero sí al fluconazol en uno (6,6%) de Candida tropicalis y uno (33,3%) del Complejo Candida parapsilosis y a la caspofungina en el aislado de Candida krusei y en uno (20%) del Complejo Candida glabrata. Conclusiones: la epidemiología local de las levaduras causantes de candidemia mostró mayor prevalencia de especies no-albicans, entre las que se encontró resistencia a los antifúngicos evaluados, lo que es relevante para la elección e instauración de un tratamiento eficaz.


2019 ◽  
Vol 9 (1) ◽  
pp. 28-39
Author(s):  
Priscilla De Bastos Souza ◽  
Valeriano Antonio Corbellini

Neste estudo foram sintetizados três derivados de 2-fenilbenzoxazol (2FBO) funcionalizados com a função azo: (2’-hidroxi-5’-fenilazofenil)benzoxazol (HFAZBO), 2-(2’-hidroxi-5’-(4’’-carboxi)fenilazofenil)benzoxazol (HFAZBO-CO2H) e 2-(2’-hidroxi-5’-(4’’-nitro)fenilazofenil)benzoxazol (HFAZBO-NO2).Os compostos foram utilizados como substratos fluorogênicos para agentes de infecção urinária, representantes de Candida spp., para explorar suas características metabólicas. A caracterização estrutural dos compostos foi realizada por meio de Espectroscopia de Absorção Molecular no Infravermelho com transformada de Fourier (FT-IR) e por determinação da faixa de fusão. Os ensaios fluorogênicos foram realizados em espécies de Candida spp.: Candida albicans ATCC 10231, Candida famata RL38, Candida glabrata 06130L, Candida glabrata RL43, Candida glabrata 0030L, Candida guilliermondii TH07, Candida krusei ATCC 6258, Candida krusei 0037L, Candida parapsilosis (RL33), Candida parapsilosis (RL38), Candida stellatoidea (9875), Candida stellatoidea (3613), Candida tropicalis ATCC 750. Não foi observada alteração sob luz uv nas leveduras testadas. Do mesmo modo, o extrato obtido a partir das colônias não apresentou fluorescência sob luz uv. Dessa forma, faz-se necessário desenvolver novos estudos que avaliem a função metabólica de Candida spp. a partir da biotransformação levando a liberação de moléculas fluorescentes.


2017 ◽  
Vol 61 (11) ◽  
Author(s):  
Wiley A. Schell ◽  
A. M. Jones ◽  
Katyna Borroto-Esoda ◽  
Barbara D. Alexander

ABSTRACT SCY-078 in vitro activity was determined for 178 isolates of resistant or susceptible Candida albicans, Candida dubliniensis, Candida glabrata, Candida krusei, Candida lusitaniae, and Candida parapsilosis, including 44 Candida isolates with known genotypic (FKS1 or FKS2 mutations), phenotypic, or clinical resistance to echinocandins. Results were compared to those for anidulafungin, caspofungin, micafungin, fluconazole, and voriconazole. SCY-078 was shown to have excellent activity against both wild-type isolates and echinocandin- and azole-resistant isolates of Candida species.


mBio ◽  
2019 ◽  
Vol 10 (5) ◽  
Author(s):  
Lohith Kunyeit ◽  
Nawneet K. Kurrey ◽  
K. A. Anu-Appaiah ◽  
Reeta P. Rao

ABSTRACT Systemic infections of Candida species pose a significant threat to public health. Toxicity associated with current therapies and emergence of resistant strains present major therapeutic challenges. Here, we report exploitation of the probiotic properties of two novel, food-derived yeasts, Saccharomyces cerevisiae (strain KTP) and Issatchenkia occidentalis (strain ApC), as an alternative approach to combat widespread opportunistic fungal infections. Both yeasts inhibit virulence traits such as adhesion, filamentation, and biofilm formation of several non-albicans Candida species, including Candida tropicalis, Candida krusei, Candida glabrata, and Candida parapsilosis as well as the recently identified multidrug-resistant species Candida auris. They inhibit adhesion to abiotic surfaces as well as cultured colon epithelial cells. Furthermore, probiotic treatment blocks the formation of biofilms of individual non-albicans Candida strains as well as mixed-culture biofilms of each non-albicans Candida strain in combination with Candida albicans. The probiotic yeasts attenuated non-albicans Candida infections in a live animal. In vivo studies using Caenorhabditis elegans suggest that exposure to probiotic yeasts protects nematodes from infection with non-albicans Candida strains compared to worms that were not exposed to the probiotic yeasts. Furthermore, application of probiotic yeasts postinfection with non-albicans Candida alleviated pathogenic colonization of the nematode gut. The probiotic properties of these novel yeasts are better than or comparable to those of the commercially available probiotic yeast Saccharomyces boulardii, which was used as a reference strain throughout this study. These results indicate that yeasts derived from food sources could serve as an effective alternative to antifungal therapy against emerging pathogenic Candida species. IMPORTANCE Non-albicans Candida-associated infections have emerged as a major risk factor in the hospitalized and immunecompromised patients. Besides, antifungal-associated complications occur more frequently with these non-albicans Candida species than with C. albicans. Therefore, as an alternative approach to combat these widespread non-albicans Candida-associated infections, here we showed the probiotic effect of two yeasts, Saccharomyces cerevisiae (strain KTP) and Issatchenkia occidentalis (ApC), in preventing adhesion and biofilm formation of five non-albicans Candida strains, Candida tropicalis, Candida krusei, Candida glabrata, Candida parapsilosis, and Candida auris. The result would influence the current trend of the conversion of conventional antimicrobial therapy into beneficial probiotic microbe-associated antimicrobial treatment.


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