Characterization of the Candida parapsilosis complex in East China: species distribution differs among cities

Abstract

Candida parapsilosis, which was previously considered to be a complex of three genetically distinct groups, has emerged as a significant agent of nosocomial infections. Recently, this complex was separated into three species: C. parapsilosis sensu stricto, C. orthopsilosis and C. metapsilosis. In China, data pertaining to these fungi are limited. In this study, we examined 57 isolates of members of the C. parapsilosis complex collected from four cities in East China, i.e., Nanjing (n = 22), Nanchang (n = 20), Shanghai (n = 12) and Jinan (n = 3). C. parapsilosis sensu stricto represented 71.9% of all isolates, while C. metapsilosis accounted for the remaining 28.1%. C. orthopsilosis could not be identified. A significantly high prevalence of C. metapsilosis was observed in strains recovered from Nanchang, 60% (12/20) of the isolates were C. metapsilosis. Sequence analysis of internal transcribed spacer region revealed two unevenly distributed genotypes among the C. metapsilosis strains. A PCR-restriction fragment length polymorphism assay was described for rapid identification. The strains were susceptible to fluconazole, voriconazole, amphoterincin B and micafungin. Six (15%) isolates of C. parapsilosis sensu stricto and three (18.8%) of C. metapsilosis were found to be dose-dependent susceptible to itraconazole. C. parapsilosis sensu stricto strains were less susceptible to micafungin than C. metapsilosis.