ABSTRACT
Antecedentes. Las estrategias terapéuticas actuales poseen una limitada eficacia para erradicar biopelículas de Candida formadas en la superficie de los dispositivos biomédicos. Pocos estudios han evaluado la eficacia de los antifúngicos sobre biopelículas de Candida tropicalis. Objetivos. Evaluar la actividad de la anfotericina B (AMB) y la anidulafungina (AND), solas y combinadas, sobre biopelículas de C. tropicalis desarrolladas en superficies de politetrafluoroetileno (teflón - PTFE) y titanio mediante ensayos de letalidad-tiempo. Métodos. Los ensayos se realizaron en un CDC Biofilm Reactor sobre biopelículas de 24h de maduración formadas en discos de PTFE y titanio. Las concentraciones ensayadas fueron 40mg/l para AMB y 8mg/l para AND, tanto para su uso por separado como combinadas. Tras 24, 48 y 72h de exposición a los antifúngicos se determinaron las ufc/cm2 mediante agitación vorticial y cultivo cuantificado previa sonicación. Resultados. AMB redujo las células viables adheridas a PTFE y titanio en más de un 99%, y AND lo hizo en un 89,3% en PTFE y 96,8% en titanio. La combinación AMB+AND fue menos activa que la AMB sola tanto en PTFE (descenso en ufc/cm2 de 3,09 Log10vs. 1,08 en la combinación) como en titanio (4,51 vs. 1,53 en la combinación), siendo la interacción indiferente en ambas superficies. Conclusiones. AMB es más activa que AND sobre biopelículas de C. tropicalis. La eficacia sobre las biopelículas es mayor en el titanio. La combinación AMB+AND es menos eficaz que AMB sola en ambas superficies (AU)
Background. Current therapeutic strategies have a limited efficacy against Candida biofilms that form on the surfaces of biomedical devices. Few studies have evaluated the activity of antifungal agents against Candida tropicalis biofilms. Objectives. To evaluate the activity of amphotericin B (AMB) and anidulafungin (AND), alone and in combination, against C. tropicalis biofilms developed on polytetrafluoroethylene (teflon -PTFE) and titanium surfaces using time-kill assays. Methods. Assays were performed using the CDC Biofilm Reactor equipped with PTFE and titanium disks with C. tropicalis biofilms after 24h of maturation. The concentrations assayed were 40mg/l for AMB and 8mg/l for AND, both alone and combined. After 24, 48 and 72h of exposure to the antifungals, the cfu/cm2 was determined by a vortexing-sonication procedure. Results. AMB reduced biofilm viable cells attached to PTFE and titanium by ≥99% and AND by 89.3% on PTFE and 96.8% on titanium. The AMB+AND combination was less active than AMB alone, both on PTFE (decrease of cfu/cm2 3.09 Log10vs. 1.08 when combined) and titanium (4.51 vs. 1.53 when combined), being the interaction irrelevant on both surfaces. Conclusions. AMB is more active than AND against C. tropicalis biofilms. Yeast killing rates are higher on titanium than on PTFE surfaces. The combination of AMB plus AND is less effective than AMB alone on both surfaces (AU)
Subject(s)
Humans , Candida tropicalis , Candida tropicalis/isolation & purification , Amphotericin B/metabolism , Amphotericin B/therapeutic use , Biofilms/classification , Biofilms , Polytetrafluoroethylene/analysis , Mortality , Antifungal Agents/analysis , Antifungal Agents/metabolism , Antifungal Agents/therapeutic use , Data Analysis/methodsABSTRACT
BACKGROUND: Current therapeutic strategies have a limited efficacy against Candida biofilms that form on the surfaces of biomedical devices. Few studies have evaluated the activity of antifungal agents against Candida tropicalis biofilms. OBJECTIVES: To evaluate the activity of amphotericin B (AMB) and anidulafungin (AND), alone and in combination, against C. tropicalis biofilms developed on polytetrafluoroethylene (teflon -PTFE) and titanium surfaces using time-kill assays. METHODS: Assays were performed using the CDC Biofilm Reactor equipped with PTFE and titanium disks with C. tropicalis biofilms after 24h of maturation. The concentrations assayed were 40mg/l for AMB and 8mg/l for AND, both alone and combined. After 24, 48 and 72h of exposure to the antifungals, the cfu/cm2 was determined by a vortexing-sonication procedure. RESULTS: AMB reduced biofilm viable cells attached to PTFE and titanium by ≥99% and AND by 89.3% on PTFE and 96.8% on titanium. The AMB+AND combination was less active than AMB alone, both on PTFE (decrease of cfu/cm2 3.09 Log10vs. 1.08 when combined) and titanium (4.51 vs. 1.53 when combined), being the interaction irrelevant on both surfaces. CONCLUSIONS: AMB is more active than AND against C. tropicalis biofilms. Yeast killing rates are higher on titanium than on PTFE surfaces. The combination of AMB plus AND is less effective than AMB alone on both surfaces.
ABSTRACT
Dermatophytes are a group of closely related fungi that have keratinase and can therefore cause infections in keratinised human and animal tissues (skin, hair and nails), leading to a disease known as dermatophytosis. This group is composed by the genera Epidermophyton, Trichophyton and Microsporum, forming an approximated total of 40 species. Depending on the source of the keratin used, dermatophytes can be divided in geophilic (soil), zoophilic (animals) and anthropophilic (human), with soil, some animals and humans being their primary habitats. Many dermatophytes can be present in both anamorphic (asexual state) or imperfect and teleomorphic state (with sexual reproduction) or perfect fungi. Anamorphic states (genera Epidermophyton, Microsporum and Trichophyton ) belong to the Hyphomycetes and phylum Deuteromycota class and teleomorphic states (the majority of geophilic and zoophilic species of Microsporum and Trichophyton) are classified in the teleomorphic genus Arthroderma, order Onygenales, phylum Ascomycota, and are usually found in their anamorphic state. Dermatophytes have a worldwide distribution, being responsible for most of the skin mycoses in both healthy and immunocompromised patients. The diagnosis and treatment of dermatophytosis are well known by most microbiologists and scientists in general. However, we describe recent techniques for their diagnosis and up-to-date treatments. The main purpose of this review is to provide a detailed description of the three genera of dermatophytes, with special mention of Epidermophyton floccosum, a object of the SEIMC's mycology quality control (M-2/09).
Subject(s)
Dermatomycoses/diagnosis , Dermatomycoses/drug therapy , Arthrodermataceae/classification , HumansABSTRACT
Los dermatofitos son un grupo de hongos, estrechamente relacionados entre sí, que poseen queratinasa y, por ello, son capaces de causar infecciones en tejidos queratinizados (piel, pelo y uñas) del hombre y animales, denominadas dermatofitosis. Según la procedencia de la queratina que utilizan, los dermatofitos se clasifican en geofílicos (suelo), zoofílicos (animales) y antropofílicos (hombre), siendo el suelo, algunos animales y el hombre sus respectivos reservorios naturales. Pertenecen a este grupo los géneros Epidermophyton, Microsporum y Trichophyton, constituyendo un total aproximado de 40 especies. Muchos dermatofitos pueden presentarse en la naturaleza en estado anamorfo (con reproducción asexual) o imperfecto y teleomorfo (con reproducción sexual) o perfecto. Los estados anamorfos (géneros Epidermophyton, Microsporum y Trichophyton) pertenecen a la clase Hyphomycetes del filum Deuteromycota (hongos imperfectos) y los estados teleomorfos (mayoría de especies zoofílicas y geofílicas de Microsporum y Trichophyton) están clasificados en el género teleomórfico Arthroderma, orden Onygenales y filum Ascomycota. Habitualmente los encontraremos como anamorfos. La distribución de los dermatofitos es universal, siendo responsables de la mayoría de las infecciones fúngicas superficiales, tanto en personas sanas como en pacientes inmunocomprometidos. El diagnóstico y tratamiento de las dermatofitosis son sobradamente conocidos por la gran mayoría de los microbiólogos; no obstante, se citarán técnicas novedosas para su diagnóstico, así como tratamientos actualizados. El (..)) (AU)
Dermatophytes are a group of closely related fungi that have keratinase and can therefore cause infections in keratinised human and animal tissues (skin, hair and nails), leading to a disease known as dermatophytosis. This group is composed by the genera Epidermophyton, Trichophyton and Microsporum, forming an approximated total of 40 species. Depending on the source of the keratin used, dermatophytes can be divided in geophilic (soil), zoophilic (animals) and anthropophilic (human), with soil, some animalsand humans being their primary habitats. Many dermatophytes can be present in both anamorphic (asexualstate) or imperfect and teleomorphic state (with sexual reproduction) or perfect fungi. Anamorphic states(genera Epidermophyton, Microsporum and Trichophyton ) belong to the Hyphomycetes and phylum Deuteromycota class and teleomorphic states (the majority of geophilic and zoophilic species of Microsporum and Trichophyton) are classified in the teleomorphic genus Arthroderma, order Onygenales, phylum Ascomycota, and are usually found in their anamorphic state. Dermatophytes have a worldwide distribution, being responsible for most of the skin mycoses in both healthy and immunocompromised patients. The diagnosis and treatment of dermatophytosis are well known by most microbiologists and scientists in general. However, we describe recent techniques for their diagnosis and up-to-date treatments. The main purpose of this review is to provide a detailed description of the three genera of dermatophytes, with special mention of Epidermophyton floccosum, a object of the SEIMCs mycology quality control (M-2/09) (AU)
