Candida orthopsilosis fungemias in a Spanish tertiary care hospital: Incidence, epidemiology and antifungal susceptibility / Fungemias por Candida orthopsilosis en un hospital terciario español: incidencia, epidemiología y sensibilidad a antifúngicos

Background. Few studies exist on prevalence of fungemia by Candida orthopsilosis, with variable results. Aims. To study the incidence, epidemiology and antifungal susceptibility of C. orthopsilosis strains isolated from fungemias over two years at a tertiary hospital. Methods. Candidemia episodes between June 2007 and June 2009 in a university hospital (Puerta del Mar, Cádiz, Spain) were studied. The strains initially identified as Candida parapsilosis were genotypically screened for C. parapsilosis sensu stricto, C. orthopsilosis and Candida metapsilosis, and their antifungal susceptibility was evaluated. Results. In this period 52 cases of candidemia were documented. Of the 19 strains originally identified as C. parapsilosis, 13 were confirmed as C. parapsilosis sensu stricto and 6 as C. orthopsilosis. Of the 52 isolates, the most frequent species were Candida albicans (30.8%), C. parapsilosis sensu stricto (25%), C. orthopsilosis, Candida tropicalis and Candida glabrata in equal numbers (11.5%). C. orthopsilosis isolates were susceptible to amphotericin B, caspofungin, voriconazole and fluconazole, with no significant differences in MIC values with C. parapsilosis sensu stricto. The source of isolates of C. orthopsilosis were neonates (50%) and surgery (50%), and 100% were receiving parenteral nutrition; however C. parapsilosis sensu stricto was recovered primarily from patients over 50 years (69.2%) and 46.1% were receiving parenteral nutrition. Conclusions. These findings show that C. orthopsilosis should be considered as human pathogenic yeast and therefore its accurate identification is important. Despite our small sample size our study suggests that a displacement of some epidemiological characteristics previously attributed to C. parapsilosis to C. orthopsilosis may be possible (AU)

Antecedentes. Apenas se han publicado estudios sobre la prevalencia de los episodios de fungemia por Candida orthopsilosis, y sus resultados han sido variables. Objetivos. Examinar la incidencia, epidemiología y sensibilidad a antifúngicos de las cepas de C. orthopsilosis aisladas de fungemias en un periodo de 2 años en un hospital de asistencia terciaria. Métodos. Entre junio de 2007 y junio de 2009, en el Hospital Universitario Puerta del Mar (Cádiz, España) se estudiaron todos los episodios de fungemia. Las cepas identificadas inicialmente como Candida parapsilosis se genotipificaron para su clasificación como C. parapsilosis sensu stricto, C. orthopsilosis y Candida metapsilosis, y se testó su sensibilidad a los antifúngicos. Resultados. Durante este periodo, se documentaron 52 episodios de fungemia. De las 19 cepas identificadas originalmente como C. parapsilosis, 13 fueron C. parapsilosis sensu stricto, y 6 C. orthopsilosis. De los 52 aislamientos, las especies más frecuentes fueron Candida albicans (30,8%), C. parapsilosis sensu stricto (25%) y C. orthopsilosis (11,5%), y Candida tropicalis y Candida glabrata fueron aisladas en igual número. Todos los aislamientos de C. orthopsilosis fueron sensibles a anfotericina B, caspofungina, voriconazol y fluconazol, sin diferencias significativas en las concentraciones inhibitorias mínimas obtenidas con C. parapsilosis sensu stricto. Los aislamientos de C. orthopsilosis procedían de recién nacidos (50%) y de pacientes sometidos a cirugía (50%). El 100% de los pacientes recibía nutrición parenteral; sin embargo, el foco de C. parapsilosis sensu stricto procedía, ante todo, de pacientes de más de 50 años de edad (69,2%), y el 46,1% recibía nutrición parenteral. Conclusiones. Los resultados del presente estudio revelan que C. orthopsilosis debe considerarse una levadura patogénica para el ser humano y, por esta razón, es importante su identificación. A pesar del pequeño tamaño de la muestra, el presente estudio evidencia el desplazamiento a C. orthopsilosis de algunas características epidemiológicas atribuidas previamente a C. parapsilosis (AU)

Studying the influence of surface topography on bacterial adhesion using spatially organized microtopographic surface patterns.

The influence of surface topography on bacterial adhesion has been investigated using a range of spatially organized microtopographic surface patterns generated on polydimethylsiloxane (PDMS) and three unrelated bacterial strains. The results presented indicate that bacterial cells actively choose their position to settle, differentiating upper and lower areas in all the surface patterns evaluated. Such selective adhesion depends on the cells' size and shape relative to the dimensions of the surface topographical features and surface hydrophobicity/hydrophilicity. Moreover, it was found that all the topographies investigated provoke a significant reduction in bacterial adhesion (30-45%) relative to the smooth control samples regardless of surface hydrophobicity/hydrophilicity. This remarkable finding constitutes a general phenomenon, occurring in both Gram-positive and Gram-negative cells with spherical or rod shape, dictated by only surface topography. Collectively, the results presented in this study demonstrate that spatially organized microtopographic surface patterns represent a promising approach to controlling/inhibiting bacterial adhesion and biofilm formation.

Candida orthopsilosis fungemias in a Spanish tertiary care hospital: incidence, epidemiology and antifungal susceptibility.

BACKGROUND: Few studies exist on prevalence of fungemia by Candida orthopsilosis, with variable results. AIMS: To study the incidence, epidemiology and antifungal susceptibility of C. orthopsilosis strains isolated from fungemias over two years at a tertiary hospital. METHODS: Candidemia episodes between June 2007 and June 2009 in a university hospital (Puerta del Mar, Cádiz, Spain) were studied. The strains initially identified as Candida parapsilosis were genotypically screened for C. parapsilosis sensu stricto, C. orthopsilosis and Candida metapsilosis, and their antifungal susceptibility was evaluated. RESULTS: In this period 52 cases of candidemia were documented. Of the 19 strains originally identified as C. parapsilosis, 13 were confirmed as C. parapsilosis sensu stricto and 6 as C. orthopsilosis. Of the 52 isolates, the most frequent species were Candida albicans (30.8%), C. parapsilosis sensu stricto (25%), C. orthopsilosis, Candida tropicalis and Candida glabrata in equal numbers (11.5%). C. orthopsilosis isolates were susceptible to amphotericin B, caspofungin, voriconazole and fluconazole, with no significant differences in MIC values with C. parapsilosis sensu stricto. The source of isolates of C. orthopsilosis were neonates (50%) and surgery (50%), and 100% were receiving parenteral nutrition; however C. parapsilosis sensu stricto was recovered primarily from patients over 50 years (69.2%) and 46.1% were receiving parenteral nutrition. CONCLUSIONS: These findings show that C. orthopsilosis should be considered as human pathogenic yeast and therefore its accurate identification is important. Despite our small sample size our study suggests that a displacement of some epidemiological characteristics previously attributed to C. parapsilosis to C. orthopsilosis may be possible.

[Cell surface hydrophobicity as an indicator of other virulence factors in Candida albicans]. / La hidrofobicidad de la superficie celular como indicador de otros factores de virulencia en Candida albicans.

OBJECTIVE: To evaluate virulence factors involved in the adhesion process, such as cell surface hydrophobicity (CSH), adherence to plastic capacity, adherence capacity to buccal epithelial cells (BEC), and biofilm formation, in 17 strains of C. albicans isolated from bronchial aspirates of critically ill patients. METHOD: The CSH of the strains of C. albicans was determined using the MATH method, a microbial adhesion to hydrocarbons test. The study of adherence to plastic was performed in microtitre plates in accordance with Christensen's technique. Biofilm formation was studied in polystyrene microtitre plates, according to the method of Ramage. Adherence to BEC was evaluated by quantifying the percentage of adhered yeasts to cells. RESULTS: All the strains studied showed factors directly involved in adhesion, with variability in the degree of expression among them. Medium-high levels of CSH were found in 52.9% of the strains. The percentage of strains with high values in adherence to plastic was 35.3%. The most hydrophobic strains were the most adherent to plastic, with a correlation coefficient of 0.76. Of the 12 biofilm-producing strains, 6 were high producers. These strains had also high levels of CSH and adherence to plastic, with significant results. All the strains studied adhered to BEC, with results ranging widely from 45 to 157 yeasts/100 BEC, with no significant correlation with the rest of the parameters studied, although CSH was seen to be an indispensable prior requisite for adherence to cells. CONCLUSION: CSH is a variable characteristic in C. albicans and is directly related to adherence to plastic and biofilm formation. Ease in evaluating CSH permits its quantification, and could be used as an indicator of the presence of other determinants of pathogenicity.

Cellular surface hydrophobicity as an additional phenotypic criterion applied to differentiate strains of Candida albicans and Candida dubliniensis.

We have evaluated the cellular surface hydrophobicity (CSH) determination as an additional criterion to differentiate Candida albicans from Candida dubliniensis. Our results show that C. albicans when grown at 37 degrees C in Sabouraud is always hydrophilic, and C. dubliniensis presents high CSH levels.

Patogenicidad de enterococcus spp. características de 169 aislamientos hospitalarios / Enterococcus spp. pathogenicity. Characteristics of 169 hospital isolates

Fundamento: Conocer las características de los aislamientos hospitalarios de Enterococcus spp., analizando la importancia de este microorganismo, así como la resistencia a los antimicrobianos. Pacientes y métodos: Análisis retrospectivo de las historias clínicas de 169 pacientes con aislamiento de Enterococcus spp., seleccionados aleatoriamente en el Hospital Infanta Cristina de Badajoz. Se investigaron la edad, el sexo, las fechas de ingreso y de alta, los síntomas clínicos, los factores de riesgo, el tratamiento antibiótico previo, la evolución clínica y microbiológica, así como el tratamiento recomendado y el tratamiento prescrito. Se identificaron los microorganismos y se llevó a cabo antibiograma con paneles microScan Pos Combo 4I, leídos en un equipo Baxter WalkAway-40. Resultados: La especie más frecuentemente hallada fue Enterococcus faecalis. En 75 casos los aislamientos fueron polimicrobianos. Los enterococos se aislaron principalmente de infecciones urinarias (27 por ciento), infecciones cutáneas (20 por ciento), infecciones intraabdominales (14 por ciento) e infección de herida quirúrgica (14 por ciento). Como factor de riesgo destacó la existencia de catéter periférico. Todas las cepas de E. faecalis fueron sensibles a los glucopéptidos. Dos cepas de Enterococcus faecium no eran sensibles a vancomicina y una de ellas tampoco a teicoplanina. La mortalidad fue del 21-27,5 por ciento. Conclusiones: Enterococcus spp. se aísla con frecuencia en infecciones hospitalarias, pero aproximadamente en la mitad de los casos se encuentra asociado a otras bacterias. Por este motivo, no siempre es posible establecer su contribución patogénica. Las cepas aisladas, excepto dos cepas de E. faecium, son sensibles a vancomicina. Existe relación entre alta resistencia a aminoglucósidos y resistencia a fluoroquinolonas (AU)