Susceptibility to heat and antifungal agents of Cryptococcus neoformans var. neoformans (serotype D) isolated from Eucalyptus spp in Rio Grande do Sul, Brazil

Horta, Jorge André; Faganello, Josiane; Kmetzsch, Lívia; Oliveira, Loiva Therezinha Ottonelli de; Santurio, Jânio M.; Vainstein, Marilene Henning; Alves, Sydney Hartz

doi:10.1590/s1517-83822005000100001

Cited by 6 publications

(4 citation statements)

References 31 publications

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“…Resistance to FLZ has previously been reported for C. gattii , and was expected to be observed in this study . Susceptibility of C. neoformans isolates was similar to that of other environmental isolates from Brazil, but susceptibility values for FLZ, ITZ and KTZ were higher than those of environmental isolates from other countries …”

Section: Discussionsupporting

confidence: 83%

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Molecular typing of environmental Cryptococcus neoformans/C. gattii species complex isolates from Manaus, Amazonas, Brazil

Alves

Freire

Bentes

et al. 2016

Mycoses

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Cryptococcus neoformans and Cryptococcus gattii are the main causative agents of cryptococcosis, a systemic fungal disease that affects internal organs and skin, and which is acquired by inhalation of spores or encapsulated yeasts. It is currently known that the C. neoformans/C. gattii species complex has a worldwide distribution, however, some molecular types seem to prevail in certain regions. Few environmental studies of Cryptococcus have been conducted in the Brazilian Amazon. This is the first ecological study of the pathogenic fungi C. neoformans/C. gattii species complex in the urban area of Manaus, Amazonas, Brazil. A total of 506 samples from pigeon droppings (n = 191), captive bird droppings (n = 60) and tree hollows (n = 255) were collected from June 2012 to January 2014 at schools and public buildings, squares, pet shops, households, the zoo and the bus station. Samples were plated on niger seed agar (NSA) medium supplemented with chloramphenicol and incubated at 25°C for 5 days. Dark-brown colonies were isolated and tested for thermotolerance at 37°C, cycloheximide resistance and growth on canavanine-glycine-bromothymol blue agar. Molecular typing was done by PCR-RFLP. Susceptibility to the antifungal drugs amphotericin B, fluconazole, itraconazole and ketoconazole was tested using Etest(®) strips. In total, 13 positive samples were obtained: one tree hollow (C. gattiiVGII), nine pigeon droppings (C. neoformansVNI) and three captive bird droppings (C. neoformansVNI). The environmental cryptococcal isolates found in this study were of the same molecular types as those responsible for infections in Manaus.

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Section: Discussionsupporting

confidence: 83%

“…The obtained results were compared to those previously reported for other C. neoformans / C. gattii species complex isolates …”

Section: Methodsmentioning

confidence: 83%

Molecular typing of environmental Cryptococcus neoformans/C. gattii species complex isolates from Manaus, Amazonas, Brazil

Alves

Freire

Bentes

et al. 2016

Mycoses

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“…neoformans é encontrado em todas as regiões do mundo, sendo que o sorotipo A predomina em isolamentos clínicos e ambientais na maioria das áreas, com exceção em países do Norte Europeu, onde o sorotipo D corresponde a 50% dos isolamentos (CASADEVALL; PERFECT, 1998). Essas diferenças geográficas na prevalência destes sorotipos têm sido relacionadas a diferenças na tolerância climática e na virulência do microrganismo (HORTA et al, 2005;BENNETT, 1992;GARCIA-RIVERA;CASADEVALL, 2001).…”

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Caracterização molecular, virulência e suscentibilidade ao fluconazol de espécies ambientais de 'Cryptococcus', antes e após inoculação em modelo murino

Pedroso¹

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Cryptococcus neoformans e C. gattii são as principais espécies do gênero que causam infecção no homem, C. albidus e C. laurentii são espécies menos envolvidas. O presente trabalho teve por objetivos avaliar a patogenicidade in vivo, os fatores e os genes relacionados à virulência, e verificar o perfil de suscetibilidade ao fluconazol de 10 isolados ambientais de cada uma das espécies: C. neoformans, C. albidus e C. laurentii, antes e após a inoculação em camundongos BALB/c imunocompetentes; pesquisar os sorotipos, mating types e realizar a tipagem molecular. Proteinase, fosfolipase, urease, produção de melanina e crescimento à 37ºC foram pesquisados utilizando metodologias clássicas, e a pesquisa dos genes e determinação dos sorotipos e mating types foram feitas por PCR. A tipagem molecular foi realizada por PCR-fingerprinting, com os iniciadores (GACA) 4 e M13. A determinação da CIM do fluconazol foi realizada pelo método da microdiluição em caldo. Todos os isolados de C. neoformans foram sorotipos A e MATα. A inoculação em animais mostrou que 9 isolados de C. neoformans mataram 100% deles em até 33 dias, e 1 levou os animais à morte num período entre 40 e 82 dias; 9 isolados foram recuperados dos pulmões e cérebro dos animais em 7 e 14 dias, e um deles levou todos os animais à morte em 12 dias, sendo possível recuperá-lo somente no 7º dia. Os animais inoculados com C. albidus e C. laurentii permaneceram vivos até negativação das culturas dos órgãos avaliados. C. albidus foi isolado principalmente do fígado e dos pulmões até 10 dias após a inoculação, C. laurentii dos pulmões e do cérebro até 120 dias. Todos os isolados das 3 espécies produziram cápsula antes e após a inoculação. Todos C. neoformans, 6 C. albidus e 6 C. laurentii cresceram à 37ºC antes e depois da inoculação. Melanina foi produzida por todos os isolados de C. neoformans e nenhum C. albidus nas duas ocasiões; e por 6 e 9 isolados de C. laurentii, antes e depois da inoculação, respectivamente. Seis isolados de C. neoformans e 1 de C. laurentii produziram proteinase nas duas ocasiões. Sete isolados de C. albidus produziram proteinase antes e todos depois da inoculação. Fosfolipase foi produzida por todos C. neoformans e C. albidus, e por 6 C. laurentii nas duas ocasiões. A avaliação da atividade da urease realizada em meio líquido foi positiva em 24 a 48 horas pelos isolados de C. neoformans e C. laurentii, e em 24 a 96 horas por C. albidus. A CIM de fluconazol variou de 2 a 8 µg/mL para C. neoformans, de 8 a ≥ 64 µg/mL para C. albidus, e de 1 a 64 µg/mL para C. laurentii, nas duas ocasiões. Todos os isolados de C. neoformans apresentaram os genes lacase (Lac1), fosfolipase (PLB1), proteinase (cnap1), calcineurina (CNA1), urease (URE1), e ERG11, com os oligonucleotídeos utilizados. A PCR com ERG11 mostrou uma banda no gel de agarose para todos C. albidus, porém nenhum dos outros genes pesquisados foram amplificados em C. albidus e C. laurentii. A tipagem molecular por PCR-fingerprinting dos isolados de C. neoformans revelou 2 tipos moleculares: VN...

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“…Características das amostras de Cryptococcus spp. isolados de pacientes atendidos no HCU,[2004][2005][2006][2007][2008][2009][2010][2011][2012][2013] Susceptibilidade in vitro aos antifúngicos pelas metodologias de disco difusão em ágar e microdiluição em caldo dos isolados de Cryptococcus neoformans de pacientes atendidos no HCU,[2004][2005][2006][2007][2008][2009][2010][2011][2012][2013] Distribuição por faixa etária e sexo dos pacientes acometidos pela Criptococose e atendidos no HCU,[2004][2005][2006][2007][2008][2009][2010][2011][2012][2013] Frequência das manifestações clínicas de pacientes com Criptococose atendidos no HCU, 2004-2013 46%) pacientes apresentaram infecção por outros microorganismos, sendo que destes, nove foram isolados da corrente sanguínea. meningoencefalite (p=0,001).…”

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Caracterização de amostras de Cryptococcus neoformans e aspectos clínicos e epidemiológicos da criptococose de pacientes do Hospital de Clínicas de Uberlândia

Aguiar¹

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Cryptococcus is a yeast-like fungus, capsuled, which has the ability to infect and cause disease in a wide variety of hosts; is the causative agent of cryptococcosis, systemic disease, subacute or chronic, occurring before the AIDS epidemic was sporadic and usually associated with patients with low cellular immunity. Two species are the main pathogenic to humans: C. neoformans and C. gattii; generally C. neoformans cause disease in immunocompromised individuals, manifested as a disease in immunocompetent individuals generally have as C. gattii agent. The laboratory diagnosis of cryptococcosis is usually performed by microbiological examinations (direct and culture research) in various clinical specimens and also by serological methods (latex reaction). Molecular techniques may also be used, but still have limited application in clinical diagnostics. Treatment is with amphotericin B in the induction phase and with fluconazole in the phases of consolidation and maintenance. The objectives of this study were to investigate the phenotypic and molecular characteristics and determine the antifungal susceptibility of Cryptococcus neoformans isolated from samples from patients treated at Uberlândia Clinical Hospital in the 2004-2013 period; and also examine the demographic characteristics of the patients. The phenotypic characteristics have been studied through the use of conventional biochemical tests, such as melanin production and urease and sensitivity to canavanine; to have the molecular characteristics, conventional PCR reactions and research have been used in the URA-5 gene by PCR-RFLP. The antifungal susceptibility was performed either by disk diffusion technique and the dilution technique broth through VITEK ® 2 system. The demographic characteristics of patients suffering from cryptococcosis were studied by analyzing the records. Between 41 samples were stored Cryptococcus identified as C. neoformans. During molecular analysis it was found that 40 were C. neoformans var. grubii (VNI) and one was C. gattii (VGI). All strains were mating type . All isolates were susceptible to antifungals front tested by automated method of broth microdilution (Vitek ® 2, Biomerieux). Patients affected by cryptococcosis were mostly men 31-40 years old, coming from urban areas. The meningoencephalitis was the predominant form of the disease; most were immunocompromised, AIDS being the predominant underlying disease. Most of them receive appropriate treatment according to the proposed guidelines; however, 58% of patients progressed to death.

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Susceptibility to heat and antifungal agents of Cryptococcus neoformans var. neoformans (serotype D) isolated from Eucalyptus spp in Rio Grande do Sul, Brazil

Cited by 6 publications

References 31 publications

Molecular typing of environmental Cryptococcus neoformans/C. gattii species complex isolates from Manaus, Amazonas, Brazil

Molecular typing of environmental Cryptococcus neoformans/C. gattii species complex isolates from Manaus, Amazonas, Brazil

Caracterização molecular, virulência e suscentibilidade ao fluconazol de espécies ambientais de 'Cryptococcus', antes e após inoculação em modelo murino

Caracterização de amostras de Cryptococcus neoformans e aspectos clínicos e epidemiológicos da criptococose de pacientes do Hospital de Clínicas de Uberlândia

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