Actividad antifúngica y perfil de seguridad del producto natural derivado del aceite de maravilla ozonizado (AMO3) en dermatofitos / In vitro antifungal susceptibility, in vivo antifungal activity and security from a natural product obtained from sunrise oil (AMO3) against dermatophytes

This work studied safety and antifungal activity of ozonized sunflower oil (AMO3) against dermatophytes. AMO3 was prepared through a new original process that modifies the oil before ozonation by alcoholic catalytic esterification. Susceptibility was studied in 41 dermatophytes by agar diffusion and broth microdilution tests. The experimental model to assess the topical safety of the oil included 60 CF1 mice divided in three groups that were treated with vaseline (control), 1 percent AMO3 and 50 percent AMO3 (overdose), respectively. Then, experimental dermatophytosis was induced in CF1 mice. Seventy-five individuals were selected and divided in 5 groups that were treated once a day with placebo, cream with 1 percent, 2 percent and 3 percent AMO3 plus an untreated control group. This new natural product showed antifungal activity against all strains studied. The MIC ranged between was 0,125 and 1 percent, while minimum fungicidal concentration (MFC) was 2 percent. The application of vaseline and AMO3 1 percent and 50 percent did not produce clinical or histopathological lesions. The mice with dermatophytosis that were treated with 1 percent, 2 percent and 3 percent AMO3 showed 100 percent clinical cure and 94 percent average mycological cure, exceeding placebo and control groups (p < 0,05). This product exhibits high antifungal activity and could be a safe alternative for ringworm topical treatment.

Se evaluó la seguridad y actividad antifúngica del aceite de maravilla ozonizado (AMO3) frente a dermatofitos. AMO3 se generó a través de un proceso original que implica modificación del aceite previa ozonización por esterificación catalítica con alcohol. La sensibilidad fue estudiada en 41 dermatofitos por difusión en agar y microdilución en caldo. El modelo experimental para evaluar tópicamente la seguridad del aceite, incluyó 60 ratones CF1, formando tres grupos a los cuales se les aplicó respectivamente vaselina (control), AMO3 1 por ciento y AMO3 50 por ciento (sobredosis). Luego, se indujo derma-tofitosis experimental en ratones CF1, seleccionando 75 individuos divididos en cinco grupos tratados una vez al día con placebo, crema con AMO3 al 1 por ciento, 2 por ciento y 3 por ciento, más un grupo control sin tratamiento. Este nuevo producto natural presentó actividad antifúngica frente a todas las cepas estudiadas. La CIM fluctuó entre 0,125 y 1 por ciento mientras la concentración fungicida mínima (CFM) fue de 2 por ciento. La aplicación de AMO3 no generó lesiones clínicas ni histopatológicas. Los ratones con dermatofitosis tratados con AMO3 presentaron 100 por ciento de cura clínica y 94 por ciento de promedio en cura micológica, siendo superior al grupo control y placebo (P < 0,05). Este producto muestra elevada actividad antimicótica y podría ser una alternativa segura para tratamiento tópico de dermatofitosis.

Susceptibilidad in vitro a anidulafungina en 100 cepas de especies de Candida aisladas previo a la introducción de esta equinocandina en Chile / In vitro andulafungin susceptibility of 100 of Candida strains obtained previously to the introduction of this echinocandin in Chile

Fungi, particularly yeasts, have become important opportunistic pathogens that can be resistant to antifungal agents or develop resistance. To address this problem, new molecules such as echinocandins, have been developed. Susceptibility to anidulafungin was studied in yeasts isolated previous to the introduction of this drug in Chile. One hundred strains of different yeast species isolated from invasive fungal infections during 2007 and 2008 were studied. Susceptibility testing of anidulafungin was performed by broth microdilution according to CLSI. All strains were susceptible to anidulafungin. MIC50 and MIC90 were 0.125 µg/mL and 1 µg/mL, respectively. Compared to other yeasts, C. parapsilosis showed a slight increase in the MICs for anidulafungin (MIC50, 1 µg/mL, MIC90, 2 µg/mL), but remained within the susceptible range. Both, fluconazole resistant (8) and dose dependant susceptible strains (16) were susceptible to anidulafungin. In vitro, this echinocandin appears to be an effective therapeutic alternative.

Los hongos, especialmente las levaduras, se han transformado en importantes patógenos oportunistas y algunos de ellos tienen o desarrollan resistencia a los antifúngicos. Para enfrentar esta problemática se han desarrollado nuevas moléculas, como las equinocandinas. Este trabajo evaluó la susceptibilidad in vitro a anidula-fungina en levaduras obtenidas previo a la incorporación de este antifúngico en Chile. Para ello, se seleccionaron 100 cepas de diversas especies aisladas de enfermedad fúngica invasora durante los años 2007 y 2008 en Chile, a las cuales se les midió la susceptibilidad in vitro por micro-dilución en caldo para anidulafungina según CLSI. Todas las cepas fueron sensibles a anidulafungina con CIM50 y CIM90 de 0,125 µg/mL y 1 µg/mL, respectivamente. Se detectó un ligero aumento de las CIM en C. parapsilosis respecto a las otras levaduras (CIM50 de 1 µg/mL y CIM90 de 2 µg/mL) considerándose estos valores en el rango de sensibilidad. La correlación de la susceptibilidad frente a fluconazol evidenció que cepas resistentes (n: 8) y sensibles dosis dependientes (n: 16) fueron sensibles a anidulafungina. Esta equinocandina aparece, in vitro, como una alternativa terapeutica efectiva frente a las levaduras aisladas en nuestros pacientes.

Infección rinosinusal por Scedosporium apiospermum en un hospedero inmunocompetente / Scedosporium apiospermum rhinosinusal infection in an immunocompetent host

Scedosporium species can cause colonization, superficial and deep localized infection or systemic disease, espe-cially in irnmunocompromised hosts. We report a case of localized infection due to Scedosporium apiospermum in a 47 year oíd woman, with previous nasal surgery. She consulted for recurrent mucopurulent post-nasal discharge not responding to antibiotics. Computed tomography showed opacification of right maxillary sinus. Surgery was performed to removed abnormal tissue from sinus; biopsy revealed chronic sinusitis with aggregate of tightly packed hyphae suggestive of filamentous fungi. The microbiology fungal culture reported Scedosporium apiospermum.

Las infecciones por Scedosporium sp pueden traducirse en colonización, infecciones localizadas superficiales y profundas, o enfermedad diseminada. Presentamos un caso clínico de infección rinosinusal por Scedosporium apiospermum en una paciente de 47 años, con antecedente de cirugía por cuerpo extraño en la fosa nasal derecha. Consultó por descarga posterior muco-purulenta y recurrente, sin respuesta a tratamiento antibacteriano. Las imágenes de cavidades paranasales mostraron opacidad del seno maxilar derecho. Se realizó cirugía de remoción de contenido sinusal cuyo estudio histológico reveló sinusitis crónica erosiva, colonias de hongos con morfología sugerente de hongo filamentoso y desarrollo de S. apiospermum en el cultivo.

Endocarditis verrucosa secundaria a saccharomyces cerevisiae: caso clínico / Saccharomyces cerevisiae endocarditis in a preterm infant: report of one case

We report a preterm infant with 30 weeks of gestation, that received broad spectrum antimicrobials during the first days of life. At nine days of life, the infant appeared with abdominal distension and hematochezia. A systolic murmur with changing auscultatory features also appeared. An echocardiography showed an atrial vegetation. A yeast, that was identified as the emergent pathogen Saccharomyces cerevisiae appeared in two blood cultures. Treatment with amphotericin B was started, the dose was adjusted calculating the minimal inhibitory concentration of amphotericin B, and measuring plasma levels of the antimicrobial. Therefore the minimal effective dose was prescribed, avoiding its deleterious effects. After 14 days of antifungal therapy, a new echocardiography showed a reduction in the size of the atrial vegetation. At 35 days, it disappeared and amphotericin B was discontinued. On the outpatient follow up, the infant has shown a normal growth and a normal cardiac auscultation

Vigilancia de la resistencia de levaduras a antifúngicos / Surveillane of antifungal drugs resistance in yeasts

Las infecciones fúngicas invasoras han aumentado en forma explosiva en los últimos 20 años. Desde la década de los 90 se ha observado un cambio continuo en el patrón etiológico de estas micosis, donde las especies del género candida son los principales agentes. Además, en los últimos años se evidencia cada vez con mayor frecuencia, el aislamiento de levaduras menos sensibles o resistentes a los antifúngicos. El objetivo de la presente publicación es revisar los antecedentes de resistencia en levaduras, tanto en el exterior como en nuestro medio y enfatizar la necesidad de mantener una red de vigilancia de resistencia

¿Es aplicable el sistema de vigilancia epidemiológica de las infecciones intrahospitalarias que recomienda el CDC-americano (sistema NNIS) en un hospital chileno? / Application of the national nosocomial infections surveillance system recommended by the CDC, in a Chilean hospital

Background: The National Nosocomial Infections Surveillance System (NNIS system) is the method for surveying nosocomial infections used by the Centers for Disease Control (CDC). This strategy allows the comparison of different hospitals, using rate adjustments. In Chile, this system is not used. Aim: To report the application of this system in a tertiary reference hospital in Chile. Materials and methods: We performed a six months prospective cohort study. The active surveillance was carried out by using the intensive care unit and surgery components of the NNIS system. Tabulation and analysis of the data were done according to the NNIS system. In a parallel prevalence study, we determined the NNIS system sensitivity to detect nosocomial infections. Results: A total of 492 patients were followed with a global nosocomial infection rate of 14 per cent, for discharged patients. The calculated sensitivity and specificity of the system was 84.2 and 97 per cent respectively. In the intensive care unit, 45 of 169 patients had nosocomial infections, with an adjusted rate of 2.8 per cent for mean hospitalization time and severity of illness. In the cardiovascular and thoracic surgical units, 216 and 107 procedures were surveyed, respectively. The global rates of nosocomial infections were 7.4 and 7.5 per cent, respectively. The adjusted rates according to risk factors were 0.9 and 2.3 per cent, respectively. Conclusions: These data indicate that the surgical units had surgical site infections rates similar to those reported by the CDC. Nosocomial infections rates in Chile can be compared with rates observed in other countries. The epidemiological data collected can be useful to focus intervention or preventive strategies