ABSTRACT
El objetivo de este trabajo fue conocer la frecuencia y el perfil de sensibilidad in vitro de aislamientos del Complejo Candida parapsilosis provenientes de casos de candidemias. Se estudiaron 754 cepas (Periodo 2008-2011), de la Red de Vigilancia de Candidemia del Instituto Nacional de Higiene Rafael Rangel. La identificación de las cepas se realizó por pruebas fenotípicas. La sensibilidad in vitro a los antifúngicos se evaluó por el método de Etest® y se determinó la concentración mínima inhibitoria a anfotericina B (AB), caspofungina (CS), fluconazol (FZ), y voriconazol (VZ). Se calcularon los puntos de corte epidemiológicos (PCE) y los rangos de cepas salvajes (PS) para cada antifúngico. El 43,6% de las cepas (n=328) fueron identificadas como Complejo C. parapsilosis; todas fueron sensibles a AB y presentaron bajos porcentajes de resistencia a FZ (4,3%), VZ (1,2%) y CS (0,6%). Los PCE y los rangos de PS (en µg/mL) fueron: FZ: 2/0,03-2; VZ y AB: 0,06/0,002-0,06 y CS: 0,5/0,002-0,5 respectivamente. Los resultados de este estudio aportaron información importante sobre el comportamiento del Complejo C. parapsilosis frente a los antifúngicos más utilizados en el tratamiento de las candidemias.
The aim of this study was to determine the frequency and in vitro susceptibility profile of Candida parapsilosis Complex isolates from patients with candidemia. Seven hundred and fifty four (754) strains (Period 2008-2011), from the Candidemia Surveillance Network of the Instituto Nacional de Higiene Rafael Rangel were studied. The strains identification was performed by phenotypic methods. In vitro antifungal susceptibility was evaluated by the Etest® method and minimum inhibitory concentration for amphotericin B (AB), caspofungin (CS), fluconazole (FZ), and voriconazole (VZ) was determined. Epidemiological cut off values (ECV) and ranges for wild type strains (WT) were also calculated for each antifungal. Forty three point six (43.6%) of the isolates (n=328) belonged to C. parapsilosis Complex; all of them were susceptible to AB and showed low resistance percentages to FZ (4.3%), VZ (1.2%) and CS (0.6%). The ECV and WT strains ranges (in mcg/mL) were: FZ: 2/0.03-2; VZ and AB: 0.06/0.002-0.06 and CS: 0.5/0.002-0.5 respectively. The results of this study provided important information about the behavior of the C. parapsilosis Complex against the most commonly antifungal agents used for the treatment of candidemias.
ABSTRACT
Objective To analyze the genotype of varicella-zoster virus (VZV) strains isolated from patients with chickenpox or zoster and to differentiate them from Oka vaccine strain by molecular analysis. Methods In the present study, single nucleotide polymorphisms(SNP) based VZV genotypes were analyzed in 19 VZV isolates using the polymerase chain reaction and restriction fragment length polymorphisms analysis of DNA fragments of the open reading frames 38, 54, 62, and the 1t5 repeat region. Results The genotypes of 19 VZV isolates including two different groups with 52.7% of Pst Ⅰ+ Bgl Ⅰ+ R5A and 47.3% of Pst Ⅰ+ Bgl Ⅰ+ R5B, which is very different from those found in North America, Europe and Japan. All the Chinese isolates are wild-type strains with ORF62 Sma Ⅰ-. No Oka vaccine strains were revealed among the isolates. Conclusion Chinese VZV strains reported in this study showed different molecular characteristics from those circulating in Europe, North America and Japan. The SNPs in ORF62 and ORF38 may be used to distinguish VZV wild-type strains and vaccine strain in clinical isolates in China.