Experimental study of specific and nonspecific blood culture bottles for the diagnosis of candidemia.

BACKGROUND: Early diagnosis of candidemia is critical for the correct management and treatment of patients. AIMS: To test the efficacy of different blood culture bottles in the growth of Candida strains. METHODS: We compared the performance of BD BACTEC™ Plus Aerobic/F (Aero) culture bottles with the specific BD BACTEC™ Mycosis IC/F Lytic (Myco) culture bottles using the BD BACTEC™ FX 40 automated blood culture system to determine the mean time-to-detection (TTD) in Candida species. One isolate each of six Candida species was inoculated into blood culture bottles (final concentration, 1-5CFUml-1) and incubated at 37°C until automated growth detection. RESULTS: Candida albicans and Nakaseomyces glabratus (Candida glabrata) were detected earlier in the specific culture bottle, whereas Candida tropicalis was detected earlier in the nonspecific bottle; Candida parapsilosis, Pichia kudriavzevii (Candida krusei), and Meyerozyma guilliermondii (Candida guilliermondii) presented similar TTD in both bottles. CONCLUSIONS: Our study suggests the suitability of using both bottles in clinical laboratories for a faster diagnosis and prompt starting of any treatment.

Especies de Candida colonizantes de cavidad oral en pacientes pediátricos oncológicos hospitalizados en el IAHULA, Mérida, Venezuela / Candida species colonizing the oral cavity of pediatric oncology patients hospitalized at the IAHULA, Merida, Venezuela

En pacientes con procesos neoplásicos, el tratamiento utilizado constituye un agente inductor del desequilibrio de la microbiota oral, permitiendo que la cavidad bucal se torne en un ambiente idóneo para la colonización y proliferación de microorganismos causantes de infecciones oportunistas como Candida spp. Se identificaron las especies de Candida colonizantes de cavidad oral en 26 pacientes pediátricos oncológicos hospitalizados en el Instituto Autónomo Hospital Universitario de Los Andes. Se tomaron muestras de la cavidad oral, se cultivaron en agar Sabouraud dextrosa con antibiótico y las levaduras fueron identificadas por métodos convencionales: formación de tubo germinal, formación de clamidoconidias, auxanograma y producción de color en el medio cromogénico Hicrome Candida agar base. Se obtuvo un 59,3% de colonización, predominando C. albicans con un 64%, seguido por las especies de Candida no albicans: C. krusei 19,5%, C. glabrata 9,8%, C. tropicalis 4,9% y C. parapsilosis 2,4%. Estas especies colonizantes no fueron concluyentes ni específicas de una patología oncológica determinada, sin embargo la estancia hospitalaria favoreció la colonización por las especies de Candida no albicans. El conocimiento de las especies colonizantes de cavidad oral ofrece información epidemiológica útil que permitirá orientar una profilaxis adecuada y un tratamiento oportuno, en caso de desarrollarse una candidiasis oral.

In patients with neoplastic processes, the treatment being used constitutes an agent which induces an unbalance of oral microbes, making the oral cavity a suitable environment for colonization and proliferation of microorganisms that produce opportunist infections such as Candida spp. In a study of 26 pediatric patients hospitalized at the Instituto Auónomo Hospital Universitario de los Andes, we identified the oral colonizing Candida spp. in these patients. Samples taken from the oral cavity were cultured in Sabouraud dextrose agar with antibiotics and the yeasts were identified by conventional methods: germinal tubes and chlamydoconidia formation, auxanogram, and color production with the medium Hicrome Candida chromogenic agar base. We determined 59.3% colonization with predomination of C. albicans in 64%, followed by non albicans Candida spp: C. krusei 19.5%, C. glabrata 9.8%, C. tropicalis 4.8%, and C. parapsilosis 2.4%. None of these colonizing species were conclusive or specific for a determined oncologic pathology; nevertheless, the hospitalization period favored colonization by non albicans Candida spp. Information about the colonizing species of the oral cavity offers useful epidemiological information for the orientation of adequate prophylaxis and opportune treatment when oral candidiasis develops.

Aislamiento y susceptibilidad a fluconazol y voriconazol de especies de Candida provenientes de pacientes recluidos en la Unidad de Cuidados Intensivos, Hospital Universitario de Coro, estado Falcón, Venezuela / Isolation and fluconazol and voriconazol sensitivity of Candida species from patients hospitalized at the Intensive Care Unit, Coro University Hospital, Falcon State, Venezuela

El objetivo de este trabajo fue determinar la frecuencia de aislamiento de Candida spp. en muestras clínicas de pacientes ingresados en una unidad de cuidados intensivos y evaluar su perfil de susceptibilidad in vitro a fluconazol y voriconazol. Se evaluaron 60 pacientes, procesándose 194 muestras: 98 hemocultivos, 48 urocultivos cuantitativos, 46 secreciones traqueales y 2 puntas de catéter, mediante siembra en agar cromogénico para Candida. El género y especie fue confirmado mediante las características macroscópicas de crecimiento, producción de clamidoconidias, hidrólisis de la urea y asimilación de carbohidratos. Para la evaluación de la susceptibilidad antifúngica se utilizó el método de difusión en disco M44-A del Clinical and Laboratory Standard Institute. Se aislaron 37 levaduras (73,0% de urocultivo en recuento significativo, 24,3% de secreción traqueal y 2,7% de punta de catéter). C. tropicalis fue la especie más frecuente (43,2%) seguida de C. glabrata (21,6%) y C. albicans (13,5%), evidenciándose una distribución diferente a la reportada en la literatura. El 73% de los aislados fue sensible a fluconazol y el 89,2% al voriconazol. La frecuencia observada de candiduria, sugiere que el urocultivo cuantitativo pudiera emplearse como estudio rutinario en pacientes recluidos en UCI, a fin de establecer estrategias terapéuticas y profilácticas adecuadas.

The aim of this work was to determine the frequency of isolation of Candida spp. in patients hospitalized in an intensive care unit and evaluate their in vitro susceptibility to fluconazol and voriconazol. Sixty patients were evaluated through 194 samples, 98 hemocultures, 48 quantitative urocultures, 46 tracheal secretions, and 2 catheter tips inoculated in Candida chromogenic agar. The genus and species was confirmed by the macroscopic growth characteristics, clamydoconidia production, urea hydrolysis, and carbohydrate assimilation. The antifungal susceptibility was determined by the disk diffusion method M44-A of the Clinical and Laboratory Standard Institute. Thirty seven yeasts were isolated (73.0% from urocultures with significant counts, 24.3% from tracheal secretion, and 2.7% from catheter tips). The most frequent species was Candida tropicalis (43.2%), followed by C. glabrata (21.6%) and C. albicans (13.5%), showing a different distribution from that reported in the literature. Regarding sensitivity, 73% of isolates were fluconazol sensitive and 89.2% voriconazol sensitive. The frequency of Candida in the urine suggests that quantitative urocultures could be used as a routine study of patients hospitalized in an ICU so as to establish adequate therapeutic and prophylactic strategies.

Identificación de especies de candida en pacientes con periodontitis apicales crónicas no supurativas / Identification of candida species in patientes with chronic apical periodontitis non suppurative

Identificar especies de Cándida en pacientes con diagnóstico de periodontitis apicales crónicas no supurativas. Se realizó un estudio descriptivo in vivo. La población fueron los pacientes con diagnóstico de periodontitis apical crónica no supurativa, que asisten a la facultad de odontología Universidad de Cartagena. Se seleccionó una muestra de 34 conductos, a los cuales se recolectó una muestra del fluido del conducto con puntas de papel, bajo condiciones de asepsia necesarias para este procedimiento. Las cepas fueron aisladas en Agar dextrosa Sabouraud e identificadas por métodos micológicos convencionales y bioquímicos. Del total de las 34 cepas estudiadas, 26 (76,5%) fueron negativas para la presencia de hongos, las 8 muestras restantes fueron positivas, lo que corresponde al 23,5 %. En la determinación de la especie, los resultados fueron positivos para Candida albicans (C. albicans) en un 17,7 % y un 5,9 % para Candida tropicalis (C. tropicalis). La presencia de especies micóticas en patologías periapicales crónicas fue positiva, prevaleciendo la C.albicans. Es importante la identificación de estos agentes en casos de periodontitis apicales crónicas no supurativas, para determinar protocolos que tengan efectividad sobre agentes micóticos.

To identify species of Candida in patients with chronic suppurative apical periodontitis. A descriptive study in vivo. The population were patients diagnosed with chronic apical suppurative periodontitis, attending dental school, University of Cartagena. A sample of 34 ducts, which collected a sample of fluid from the canal with paper points, under aseptic conditions necessary for this procedure. The strains were isolated on Sabouraud dextrose agar and identified by conventional mycological and biochemical methods. A total of 34 strains studied, 26 (76.5%) were negative for the presence of fungi, the remaining 8 samples were positive, corresponding to 23.5%. In determining the species, the results were positive for C. albicans in 17.7% and 5.9% for C. tropicalis. The presence of fungal species in chronic periapical pathology was positive with C. albicans prevailing. It is important to identify these agents in cases of chronic suppurative apical periodontitis, to establish protocols or medicaments that will be effective against fungal agents.

Susceptibilidad a fluconazol y voriconazol por el método de disfusión de cepas de candida, aisladas de hemocultivos en Maracaibo, Venezuela / Susceptibility to fluconazole and voriconazole in candida strains isolated from blood culture by disk diffusion method Maracaibo, Venezuela

Para determinar la susceptibilidad de cepas de Candida aisladas de hemocultivos en nuestro medio, se estudiaron 78 cepas obtenidas de pacientes hospitalizados en diferentes servicios del Servicio Autónomo Hospital Universitario de Maracaibo (SAHUM), Venezuela. Para la identificación de especies se usó el medio cromogénico Brilliance Candida Agar y Vitek-YBC. Adicionalmente, los cultivos fueron identificados por el método tradicional. La susceptibilidad fue determinada por el método de difusión con discos de fluconazol y voriconazol según la metodología M44-A2 del Clinical Laboratory Standard Institute. La frecuencia de las especies de Candida fue: C. parapsilosis 51,28%, C. tropicalis 15,38%, C. guilliermondii 11,54%, C. albicans 10,26% C. famata 6,41%, C. glabrata 3,85% y C. krusei 1,28%. La susceptibilidad fue de 96,15% y 100% para fluconazol y voriconazol, respectivamente. Tres de las 78 cepas, identificadas como C. albicans, C. guilliermondii y C. krusei fueron resistentes a fluconazol. Estos resultados sugieren que fluconazol y voriconazol pueden ser utilizados en el tratamiento de pacientes con candidemia en SAHUM, sin embargo, la vigilancia epidemiológica y la determinación de la susceptibilidad de Candida deben mantenerse

To determine the susceptibility of Candida strains isolated from blood cultures in Maracaibo, Venezuela, 78 strains obtained from hospitalized patients in different services of the autonomous Maracaibo University Hospital, Venezuela, were studied. Chromogenic Medium Brilliance Candida Agar and Vitek-YBC were used for species identification. In addition, cultures were assessed using the traditional identification method. Susceptibility was determined by the diffusion method with fluconazole and voriconazole disks, according to the Clinical and Laboratory Standard Institute, Document M44-A2. Frequency of the Candida species was: C. parapsilosis 51.28%, C. tropicalis 15.38%, C. guilliermondii 11.54%, C. albicans 10.26% C. famata 6.41%, C. glabrata 3.85% and C. krusei 1.28%. Susceptibility was 96.15% and 100% for fluconazole and voriconazole, respectively. Three isolates identified as C. albicans, C. guilliermondii and C. krusei were resistant to fluconazole. These results suggest that fluconazole and voriconazole can be useful in the treatment of patients with candidemia; however, epidemiological surveillance and susceptibility pattern determination of Candida must be maintained

Candidemia em hospital terciário do nordeste do Brasil / Candidemia in a tertiary hospital in northeastern Brazil

Realizou-se um estudo observacional, prospectivo, de base laboratorial, para investigar a incidência de candidemia, distribuição de espécies e condições clínicas entre setembro 2003 e março 2004, em um hospital privado terciário em Recife, Nordeste do Brasil. Um caso de candidemia foi definido como isolamento de Candida spp de hemocultura. A taxa de incidência foi calculada por 1.000 admissões. Um total de 5.532 pacientes foram admitidos no hospital durante o período de estudo, e 1.745 culturas de sangue foram processadas. Foram observados 21 episódios de candidemia em 18 pacientes. A taxa de incidência de candidemia foi de 3,9 episódios por 1.000 admissões. Espécies não-albicans representaram mais de 50 por cento dos casos, predominando Candida parapsilosis (33 por cento) e Candida tropicalis (24 por cento). Onze (61 por cento) pacientes morreram. A incidência de candidemia foi mais alta que aquela observada em estudo multicêntrico brasileiro. Candidemia foi predominantemente causada por espécies não-albicans.

We conducted a prospective, observational, laboratory-based study on candidemia to investigate the incidence of candidemia, species distribution and clinical conditions between September 2003 and March 2004 in a private tertiary hospital in Recife, northeastern Brazil. Cases of candidemia were defined as occurrences of isolation of Candida spp from blood cultures. The incidence rate was calculated per 1,000 admissions. A total of 5,532 patients were admitted to the hospital during the study period, and 1,745 blood cultures were processed. Twenty-one episodes of candidemia were observed in 18 patients. The incidence rate of candidemia was 3.9 episodes per 1,000 admissions. Non-albicans species accounted for more than 50 percent of the cases, and Candida parapsilosis (33 percent) and Candida tropicalis (24 percent) predominated. Eleven (61 percent) patients died. The incidence of candidemia was higher than that observed in a Brazilian multicenter study. Candidemia was caused predominantly by non-albicans species.

Estudo comparativo da atividade antifúngica de cimentos endodônticos e do agregado de trióxido mineral (MTA) / Comparative study of the antifungal activity of endodontic sealers and mineral trioxide aggregate (MTA)

O objetivo deste estudo in vitro, foi avaliar a atividade antifúngica do ProRoot MTA (agregado de trióxido mineral) e de sete cimentos endodônticos contra as seguintes espécies: Candida albicans, Candida glabrata, Candida tropicalis e Saccharomyces cerevisiae. O teste de difusão em ágar foi o método utilizado. Placas de Petri contendo o meio triptcase-soja ágar foram inoculadas com cada espécie de fungo testada ou com saliva humana, representativa de uma cultura microbiana mista. Os resultados permitiram classificar os cimentos testados em ordem decrescente de eficácia antifúngica: Intrafil, AH Plus, Kerr Pulp Canal Sealer, Epiphany, MTA, Sealer 26, Acroseal e Roeko Seal. Nenhum material foi eficaz contra todas as espécies testadas.

Evaluation of biochemical and serological methods to identify and clustering yeast cells of oral Candida species by CHROMagar test, SDS-PAGE and ELISA

The purpose of this work was to evaluate biochemical and serological methods to characterize and identify Candida species from the oral cavity. The strains used were five Candida species previously identified: C. albicans, C. guilliermondii, C. parapsilosis, C. krusei, C. tropicalis, and Kluyveromyces marxianus, as a negative control. The analyses were conducted through the SDS-PAGE associated with statistical analysis using software, chromogenic medium, and CHROMagar Candida (CA), as a differential medium for the isolation and presumptive identification of clinically important yeasts and an enzyme-linked immunoabsorbent assay (ELISA), using antisera produced against antigens from two C. albicans strains. This method enabled the screening of the three Candida species: C. albicans, C. tropicalis, and C. Krusei, with 100% of specificity. The ELISA using purified immunoglobulin G showed a high level of cross-reaction against protein extracts of Candida species. The SDS-PAGE method allowed the clustering of species-specific isolates using the Simple Matching coefficient, S SM = 1.0. The protein profile analysis by SDS-PAGE increases what is known about the taxonomic relationships among oral yeasts. This methodology showed good reproducibility and allows collection of useful information for numerical analysis on information relevant to clinical application, and epidemiological and systematical studies.

Este trabalho teve o propósito de avaliar métodos bioquímicos e sorológicos para serem aplicados na caracterização e identificação de linhagens do gênero Candida isoladas da cavidade bucal. As cepas empregadas representam cinco espécies de Candida previamente identificadas: C. albicans, C. guilliermondii, C. parapsilosis, C. krusei e C. tropicalis, utilizando como controle negativo Kluyveromyces marxianus. Foram empregadas as técnicas de gel de poliacrilamida (SDS-PAGE) associado à análise estatística em software, CHROMagar Candida (CA), meio cromogênico diferencial descrito para o isolamento e identificação presuntiva de leveduras de importância clínica e um ensaio de imunoabsorção ligado a enzima (ELISA), utilizando antissoro produzido contra extratos protéicos de uma linhagem-padrão de Candida e um isolado de cavidade oral de C. albicans. O método mostrou-se adequado para a identificação presuntiva de C. albicans, C. tropicalis e C. krusei, com 100% de sensibilidade e especificidade, com base na coloração e textura das colônias. O método de ELISA utilizando imunoglobulinas G purificadas apresentou alto teor de reação cruzada com as outras espécies de Candida estudadas. A análise do perfil protéico por SDS-PAGE permitiu agrupar os isolados da cavidade oral por intermédio do coeficiente "Simple Matching", S SM = 1,0. Os perfis protéicos analisados por SDS-PAGE ampliam os conhecimentos sobre as relações taxonômicas de leveduras isoladas da cavidade oral. Esta metodologia demonstra boa reprodutibilidade e origina informações úteis para aplicação clínica e estudos que envolvem a sistemática e a epidemiologia.