Five-Year National Surveillance of Invasive Candidiasis: Species Distribution and Azole Susceptibility from the China Hospital Invasive Fungal Surveillance Net (CHIF-NET) Study

Data on the epidemiology of invasive candidiasis (IC) and the antifungal susceptibility of Candida isolates in China are still limited. Here we report on surveillance for IC from the China Hospital Invasive Fungal Surveillance Net (CHIF-NET) study. Sixty-five tertiary hospitals collected 8,829 Candida isolates from 1 August 2009 to 31 July 2014. Matrix-assisted laser desorption ionization-time of flight mass spectrometry supplemented by ribosomal DNA sequencing was used to define the species, and the fluconazole and voriconazole susceptibilities were determined by the Clinical and Laboratory Standards Institute disk diffusion method. A total of 32 Candida species were identified. Candida albicans was the most common species (44.9%), followed by the C. parapsilosis complex (20.0%), C. tropicalis (17.2%), and the C. glabrata complex (10.8%), with other species comprising <3% of isolates. However, in candidemia, the proportion of cases caused by C. albicans was only 32.3%. C. albicans and C. parapsilosis complex isolates were susceptible to fluconazole and voriconazole (<6% resistance), while fluconazole and azole cross-resistance rates were high in C. tropicalis (13.3% and 12.9%, respectively), C. glabrata complex (18.7% and 14%, respectively), and uncommon Candida species (44.1% and 10.3%, respectively) isolates. Moreover, from years 1 to 5 of the study, there was a significant increase in the rates of resistance to fluconazole among C. glabrata complex isolates (12.2% to 24.0%) and to both fluconazole (5.7% to 21.0%) and voriconazole (5.7% to 21.4%) among C. tropicalis isolates (P < 0.01 for all comparisons). Geographic variations in the causative species and susceptibilities were noted. Our findings indicate that antifungal resistance has become noteworthy in China, and enhanced surveillance is warranted.