Caracterização de Candida spp isoladas de hemocultivo e aspectos clínicos de candidemia

Abstract

Increases in invasive infection by yeasts of the genus Candida constitute a serious public health issue. Worldwide, non-C. albicans Candida species have recently emerged as agents of candidemia. The purposes of this study were to describe the demographic and clinical characteristics of 32 patients with laboratory diagnosis of candidemia, identify the infective species, and determine their antifungal susceptibility profiles. The study was conducted at the teaching hospital of the Universidade Federal de Mato Grosso do Sul in Campo Grande, Mato Grosso do Sul state, Brazil, from March 2010 to March 2012. Fungal identification was based on phenotypic testing (CHROMagar Candida, microculture, auxanogram) and an automated Vitek 2 system. Minimum inhibitory concentrations of fluconazole, voriconazole, itraconazole, and amphotericin B were determined by broth microdilution, according to the M27-A3 document of the Clinical and Laboratory Standards Institute. PCR-RFLP was employed for differentiation of species in the Candida parapsilosis complex. Overall, C. albicans was the species most often isolated (34.4%), followed by the C. parapsilosis complex (21.9%), C. guilliermondii (15.6%), C. glabrata/C. tropicalis (12.5%), and C. krusei (3.1%). Non-C. albicans Candida species accounted for 65.6% of cases. Of the species pertaining to the C. parapsilosis complex, five isolates were C. parapsilosis stricto sensu and two were C. orthopsilosis. Most yeasts were sensitive to the antifungals tested. The susceptibility of all C. glabrata isolates was dose-dependent to fluconazole and all isolates proved itraconazole-resistant. Of five C. guilliermondii isolates, one was dose-dependently sensitive to fluconazole and all were dose-dependently susceptible to itraconazole. Candidemia incidence was higher (46.9%) among patients aged 60 years and older, as well as in critical groups, including those admitted to intensive care units (40.6%) or on hemodialysis (21.9%). Three patients acquired bloodstream infection related to central venous catheters. Of the 32 patients, 47% died. Multivariate analysis revealed an association between the higher number of deaths among patients with C. albicans bloodstream infection than among those infected with non-C. albicans Candida species (p ≤ 0.05). The study revealed an emergence of non-C. albicans Candida species—particularly the C. parapsilosis complex, C. guilliermondii, and C. glabrata—as agents of candidemia in the hospital investigated. PCR-RFLP proved useful in differentiating species of the C. parapsilosis complex.