Surveillance of the prevalence, antibiotic susceptibility, and genotypic characterization of invasive candidiasis in a teaching hospital in China between 2006 to 2011

Abstract

BackgroundInvasive candidiasis is an important nosocomial infection associated with high mortality among immunosuppressive or critically ill patients. We described the incidence of invasive candidiasis in our hospital over 6 years and showed the antifungal susceptibility and genotypes of the isolated yeast.MethodThe yeast species were isolated on CHROMagar Candida medium and identified using an yeast identification card, followed by analysis of the D1/D2 domain of 26S rDNA. The susceptibilities of the isolates to flucytosine, amphotericin B, fluconazole, itraconazole, and voriconazole were tested using the ATB FUNGUS 3 system, and that to caspofungin was tested using E-test strips. C. albicans was genotyped using single-strand conformation polymorphism of CAI (Candida albicans I) microsatellite DNA combined with GeneScan data.ResultsFrom January 2006 to December 2011, a total of 259 isolates of invasive Candida spp. were obtained from 253 patients, among them 6 patients had multiple positive samples. Ninety-one stains were from blood and 168 from sterile fluids, accounting for 6.07% of all pathogens isolated in our hospital. Most of these strains were C. albicans (41.29% in blood/59.06% in sterile body fluids), followed by C. tropicalis (18.06%/25.72%), C. parapsilosis (17.42%/5.43%), C. glabrata (11.61%/3.99%) and other Candida spp. (11.61%/5.80%). Most Candida spp. were isolated from the ICU. The new species-specific CLSI candida MIC breakpoints were applied to these date. Resistance to fluconazole occurred in 6.6% of C. albicans isolates, 10.6% of C. tropicalis isolates and 15.0% of C. glabrata isolates. For the 136 C. albicans isolates, 54 CAI patterns were recognized. The C. albicans strains from blood or sterile body fluids showed no predominant CAI genotypes. C. albicans isolates from different samples from the same patient had the same genotype.ConclusionsInvasive candidiasis has been commonly encountered in our hospital in the past 6 years, with increasing frequency of non-C. albicans. Resistance to fluconazole was highly predictive of resistance to voriconazole. CAI SSCP genotyping showed that all C. albicans strains were polymorphic. Invasive candidiasis were commonly endogenous infection.

In Vitro Antidrug Susceptibility Testing of Candida Species Isolated from Aseptic Body Fluids

“…Candida infection rates in the departments of ICU and Urology were most predominant (34.9% and 30.2%, respectively), which is consistent with the distributions reported in the US (25). This is possible because the patients in ICUs may be immunocompromised or critically ill, and they were more likely to be infected with Candida.…”

“…It may be because of prescribing habits in clinics; fluconazole was not commonly used to treat the infections of the bloodstream and other sterile sites. Some surveillance had shown that resistance to fluconazole was highly predictive of resistance to voriconazole (25,29). In this regard, we found that 16 out of 20 fluconazole-resistant C. albicans were cross-resistant to itraconazole.…”

Application of caspofungin in China compared with amphotericin B and fluconazole

“…Candida and invasive aspergillosis, which are typical fungi, are responsible for serious levels of morbidity and mortality. It is reported that the mortality rate of invasive aspergillosis infection is >30% in China, similar with other countries and districts 6–8…”

Sensitive and rapid RT-qPCR quantification of pathogenic Candida species in human blood

“…Candida albicans is the most common species isolated (Li et al, 2013;Pfaller et al, 2010Pfaller et al, , 2011Rodloff et al, 2011;Takakura et al, 2004), and non-albicans Candida species (NACs), including Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei, which are less sensitive than C. albicans to azole antifungal drugs, are isolated at the next-highest frequencies; together with C. albicans they account for more than 90% of Candida bloodstream infections (Hajjeh et al, 2004;Pfaller and Diekema, 2007). The occurrence of NAC bloodstream infections is increasing in several regions (Chang et al, 2008;Li et al, 2013;Pfaller and Diekema, 2007;Pfaller et al, 2010;Rodloff et al, 2011;Takakura et al, 2004). In addition, differences in causative Candida species among age groups have been reported, with higher occurrences of C. glabrata bloodstream infections in the elderly and of C. parapsilosis and C. tropicalis infections in neonates (Juyal et al, 2013;Malani et al, 2005).…”