ABSTRACT
The aim of this study was to report the ability of killer toxins, previously used as biotyping techniques, as a new tool to differentiate C. albicans from C. dubliniensis. The susceptibility of C. albicans and C. dubliniensis to killer toxins ranged from 33.9 to 93.3% and from 6.67 to 93.3%, respectively.
Subject(s)
Candida/classification , Candida/drug effects , Cytotoxins/pharmacology , Killer Factors, Yeast/pharmacology , Mycological Typing Techniques/methods , Candida albicans/drug effects , Microbial Sensitivity TestsABSTRACT
The aim of this study was to report the ability of killer toxins, previously used as biotyping techniques, as a new tool to differentiate C. albicans from C. dubliniensis. The susceptibility of C. albicans and C. dubliniensis to killer toxins ranged from 33.9 to 93.3 percent and from 6.67 to 93.3 percent, respectively.
Avaliou-se a capacidade das toxinas killer, previamente utilizadas na biotipagem de C. albicans, como método para diferenciar C. albicans de C. dubliniensis. A susceptibilidade de C. albicans e C. dubliniensis às toxinas killer variou de 33,9 por cento a 93,3 por cento para C. albicans e de 6,67 por cento a 93,3 por cento para C. dubliniensis.
Subject(s)
Candida/classification , Candida/drug effects , Cytotoxins/pharmacology , Killer Factors, Yeast/pharmacology , Mycological Typing Techniques/methods , Candida albicans/drug effects , Microbial Sensitivity TestsABSTRACT
Candida dubliniensis is an emerging pathogen first described in 1995, which shares many phenotypic features with Candida albicans and therefore may be misidentified in microbial laboratories. Despite various phenotypic techniques described in the literature to differentiate the two species, the correct identification of C. dubliniensis remains problematic due to phenotypic similarities between these species. Thus, as the differences between both are best characterized at genetic levels, several molecular methods have been proposed to provide a specific and rapid identification of this species. Epidemiological studies have shown that C. dubliniensis is prevalent throughout the world and it is primarily associated with oral carriage and oropharyngeal infections in patients infected with human immunodeficiency virus (HIV). However, data acquired from its isolation from other healthy and immunocompromised patients are variable, and there is still no real consensus on the epidemiological relevance of this species. In this article, we review the various phenotypic methods used in the identification of C. dubliniensis and the epidemiological impact of this new species.
Subject(s)
Candida albicans , Candida , Candidiasis, Oral/diagnosis , Candidiasis, Oral/epidemiology , AIDS-Related Opportunistic Infections/complications , AIDS-Related Opportunistic Infections/epidemiology , Candida/classification , Candida/genetics , Candida/isolation & purification , Candida albicans/classification , Candida albicans/genetics , Candida albicans/isolation & purification , Candidiasis, Oral/microbiology , Child , Culture Media , Female , HIV Infections/complications , HIV Infections/epidemiology , Humans , Male , Molecular Epidemiology , Mycological Typing Techniques/methods , Oropharynx/microbiology , Phenotype , Prevalence , Species SpecificityABSTRACT
In this study, the susceptibility to amphotericin B of Candida spp. isolates obtained from patients with candidemia was related to their respective clinical outcomes. The susceptibility tests were carried out in three culture media: RPMI 1640, Antibiotic medium 3 and Yeast Nitrogen Base dextrose. We have found that minimal inhibitory concentrations and minimal fungicidal concentrations obtained using AM3 and YNBd media were significantly higher for Candida spp. from patients who died than for those from patients who survived the candidemia (P < 0.05). The assays with RPMI 1640 medium did not show these differences.
Subject(s)
Amphotericin B/pharmacology , Antifungal Agents/pharmacology , Candida/drug effects , Candidiasis , Drug Resistance, Fungal , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Candidiasis/microbiology , Candidiasis/mortality , Candidiasis/therapy , Culture Media , Humans , Microbial Sensitivity Tests , Treatment OutcomeABSTRACT
We evaluated a new selective indicator medium (UNISC Agar) for isolation of classical enteropathogens, Aeromonas spp and Plesiomonas shigelloides. The xylose fermentation capacity is indicated by a yellow color (fermenting agents) or blue (no fermenting agent). This, together with the oxidase test, establishes it as an indicator for detecting Aeromonas and Plesiomonas shigelloides. Its productivity and selectivity, as assessed using the absolute count index and relative count index, indicate it as an alternative to the classical feces culturing media. This is because, in a single medium, it enables isolation of Escherichia coli, Shigella spp and Salmonella spp, in addition to Aeromonas and Plesiomonas shigelloides, thereby favoring the laboratory diagnosis of gastroenteritis.
Subject(s)
Aeromonas/isolation & purification , Culture Media/chemistry , Plesiomonas/isolation & purification , Feces/microbiology , HumansABSTRACT
Avaliou-se um novo meio seletivo-indicador (ágar UNISC) para o isolamento de enteropatógenos clássicos e Aeromonas e Plesiomonas shigelloides. A capacidade de fermentação da xilose é indicada pela coloração amarela (fermentadores) ou azul (não fermentadores) que, aliada à prova da oxidase, constitui-se em indicador para a detecção de Aeromonas spp e Plesiomonas shigelloides. A produtividade e seletividade, avaliadas pelos índice de contagem absoluta e índice de contagem relativa indicam-no como uma alternativa aos coprocultivos clássicos porque permite, num só meio, o isolamento de Escherichia coli, Shigella spp, Salmonella spp, bem como, Aeromonas spp e Plesiomonas shigelloides, favorecendo o diagnóstico laboratorial das gastroenterites.
We evaluated a new selective indicator medium (UNISC Agar) for isolation of classical enteropathogens, Aeromonas spp and Plesiomonas shigelloides. The xylose fermentation capacity is indicated by a yellow color (fermenting agents) or blue (no fermenting agent). This, together with the oxidase test, establishes it as an indicator for detecting Aeromonas and Plesiomonas shigelloides. Its productivity and selectivity, as assessed using the absolute count index and relative count index, indicate it as an alternative to the classical feces culturing media. This is because, in a single medium, it enables isolation of Escherichia coli, Shigella spp and Salmonella spp, in addition to Aeromonas and Plesiomonas shigelloides, thereby favoring the laboratory diagnosis of gastroenteritis.
Subject(s)
Humans , Aeromonas/isolation & purification , Culture Media/chemistry , Plesiomonas/isolation & purification , Feces/microbiologyABSTRACT
The purpose of the present study is to compare the tomato juice agar, a well known medium employed to observe ascospore formation, with niger seed agar, casein agar and sunflower seed agar, applied to a differentiation between C. dubliniensis and C. albicans. After 48 hours of incubation at 30 degrees C all 26 (100%) C. dubliniensis isolates tested produced chlamydospores on tomato juice agar as well as in the other three media evaluated. However, when we inoculated all media with C. albicans, the absence of chlamydospores became resulting in the following percents: tomato juice agar (92.47%), niger seed agar (96.7%), casein agar (91.39%), and sunflower seed agar (96.7%). These results indicate that tomato juice agar is another medium which can also be used in the first phenotypic differentiation between C. dubliniensis and C. albicans.
Subject(s)
Agar/chemistry , Candida/classification , Culture Media/chemistry , Candida/growth & development , Candida/isolation & purification , Candida albicans/classification , Candida albicans/growth & development , Solanum lycopersicum , Mycological Typing Techniques/methods , Spores, Fungal/growth & developmentABSTRACT
O presente estudo teve como objetivo comparar o ágar suco de tomate, um tradicional meio utilizado para observação de ascósporos em leveduras, com o ágar semente de niger, ágar caseína e ágar semente de girassol, na diferenciação fenotípica entre C. albicans e C. dubliniensis. Após 48 h de incubação a 30 ºC, os 26 isolados de C. dublinienis (100%) evidenciaram a formação de clamidoconídios igualmente em todos os meios comparados. Entretanto, quando semeados com C. albicans, a formação de clamidoconídios foi raramente observada, resultando nos seguintes percentuais de ausência destas estruturas: ágar suco de tomate (92,47%), ágar niger (96,7%), ágar caseína (91,39%), ágar semente de girassol (96,7%). Estes resultados permitem-nos sugerir a utilização do ágar suco de tomate como mais um meio que, já no primo-isolamento, é capaz de, presuntivamente, diferenciar C. albicans de C. dubliniensis.
Subject(s)
Agar/chemistry , Candida/classification , Culture Media/chemistry , Candida albicans/classification , Candida albicans/growth & development , Candida/growth & development , Candida/isolation & purification , Solanum lycopersicum , Mycological Typing Techniques/methods , Spores, Fungal/growth & developmentABSTRACT
The purpose of the present study was to evaluate the identification of 19 Brazilian C. dubliniensis based on the biochemical profile exhibited when tested by the commercial identification kit ID 32C (bioMerieux). Thirteen of the isolates were rigorously identified as C. dubliniensis and the remaining isolates (six) were considered as having a doubtful profile but the software also suggested that there was 83.6% of chances for them to be C. dubliniensis. As well as pointed by the literature the identification obtained by phenotypic tests should be considered presumptive for C. dubliniensis due to variability of this new species.
Subject(s)
Candida/classification , Carbohydrate Metabolism , Mycological Typing Techniques/methods , Candida/isolation & purification , Candida/metabolism , Humans , PhenotypeABSTRACT
Dezenove culturas de C. dubliniensis isoladas no Brasil, previamente identificadas através de métodos genotípicos, foram avaliadas pelo kit comercial ID 32C (bioMerieux). Treze culturas foram identificadas como C. dubliniensis, mas as demais (seis) evidenciaram perfil duvidoso, embora o software do sistema sugerisse 83,6% de chances das mesmas pertencerem à espécie C. dubliniensis. A literatura tem registrado grande variabilidade fenotípica com esta espécie e, por isto, as identificações obtidas com este sistema deverão ser consideradas como presuntivas.
Subject(s)
Humans , Candida/classification , Carbohydrates/metabolism , Mycological Typing Techniques/methods , Candida/isolation & purification , Candida/metabolism , PhenotypeABSTRACT
Relata-se um caso de dermatose devido a infestação causada por ácaros do gênero Cheyletus. Aspectos do diagnóstico eocorrência desta rara infestação são também discutidos...
