Comparative Evaluation of the BD Phoenix Yeast ID Panel and Remel RapID Yeast Plus System for Yeast Identification

Becton Dickinson Phoenix Yeast ID Panel was compared to the Remel RapID Yeast Plus System using 150 recent clinical yeast isolates and the API 20C AUX system to resolve discrepant results. The concordance rate between the Yeast ID Panel and the RapID Yeast Plus System (without arbitration) was 93.3% with 97.3% (146/150) and 95.3% (143/150) of the isolates correctly identified by the Becton Dickinson Phoenix and the Remel RapID, respectively, with arbitration.

SUSCEPTIBILITY TEST FOR FUNGI: CLINICAL AND LABORATORIAL CORRELATIONS IN MEDICAL MYCOLOGY

During recent decades, antifungal susceptibility testing has become standardized and nowadays has the same role of the antibacterial susceptibility testing in microbiology laboratories. American and European standards have been developed, as well as equivalent commercial systems which are more appropriate for clinical laboratories. The detection of resistant strains by means of these systems has allowed the study and understanding of the molecular basis and the mechanisms of resistance of fungal species to antifungal agents. In addition, many studies on the correlation of in vitro results with the outcome of patients have been performed, reaching the conclusion that infections caused by resistant strains have worse outcome than those caused by susceptible fungal isolates. These studies have allowed the development of interpretative breakpoints for Candida spp. and Aspergillus spp., the most frequent agents of fungal infections in the world. In summary, antifungal susceptibility tests have become essential tools to guide the treatment of fungal diseases, to know the local and global disease epidemiology, and to identify resistance to antifungals.

Temporal Trends of the Clinical, Resource Use and Outcome Attributes of ICU-Managed Candidemia Hospitalizations: A Population-Level Analysis

BACKGROUND

There are mixed findings on the longitudinal patterns of the incidence of intensive care unit (ICU)-managed candidemia, with scarcity of reports on the corresponding evolving patterns of patients' clinical characteristics and outcomes. No population-level data were reported on the temporal trends of the attributes, care and outcomes of ICU-managed adults with candidemia.

METHODS

The Texas Inpatient Public Use Data File was used to identify hospitalizations aged 18 years or older with a diagnosis of candidemia and ICU admission (C-ICU hospitalizations) between 2001 and 2010. Temporal trends of the demographics, clinical features, use of healthcare resources, and short-term outcomes were examined. Average annual percent changes (AAPCs) were derived.

RESULTS

C-ICU hospitalizations (n = 7,552) became (AAPC) increasingly younger (age ≥ 65 years: -1.0%/year). The Charslon comorbidity index rose 4.2%/year, while the mean number of organ failures (OFs) increased by 8.2%/year, with a fast rise in the rate of those developing ≥ 3 OFs (+15.5%/year). Between 2001 and 2010, there was no significant change in utilization of mechanical ventilation and new hemodialysis among C-ICU hospitalizations with reported respiratory and renal failures (68.9% vs. 73.3%, P = 0.3653 and 15.5% vs. 21.8%, P = 0.8589, respectively). Hospital length of stay or total hospital charges remained unchanged during study period. Hospital mortality decreased between 2001 and 2010 from 39.3% to 23.8% (-5.2%/year). The majority of hospital survivors (61.6%) were discharged to another facility, and increasingly to long-term acute care hospitals, with routine home discharge decreasing to 11% by 2010.

CONCLUSIONS

C-ICU hospitalizations demonstrated increasing comorbidity burden and rising development of OF, and matching rise in use of selected life-support interventions, though with unchanged in-hospital fiscal impact. There has been marked decrease in hospital mortality, but survivors had substantial residual morbidity with the majority discharged increasingly to another post-acute care facility.

Antifungal Susceptibility in Serum and Virulence Determinants of Candida Bloodstream Isolates from Hong Kong

Candida bloodstream infections (CBI) are one of the most common nosocomial infections globally, and they account for a high mortality rate. The increasing global prevalence of drug-resistant Candida strains has also been posing a challenge to clinicians. In this study, we comprehensively evaluated the biofilm formation and production of hemolysin and proteinase of 63 CBI isolates derived from a hospital setting in Hong Kong as well as their antifungal susceptibility both in the presence and in the absence of human serum, using standard methodology. Candida albicans was the predominant species among the 63 CBI isolates collected, and non-albicans Candida species accounted for approximately one third of the isolates (36.5%). Of them, Candida tropicalis was the most common non-albicans Candida species. A high proportion (31.7%) of the CBI isolates (40% of C. albicans isolates, 10% of C. tropicalis isolates, 11% of C. parapsilosis isolates, and 100% of C. glabrata isolates) were found to be resistant to fluconazole. One of the isolates (C. tropicalis) was resistant to amphotericin B. A rising prevalence of drug-resistance CBI isolates in Hong Kong was observed with reference to a previous study. Notably, all non-albicans Candida species, showed increased hemolytic activity relative to C. albicans, whilst C. albicans, C. tropicalis, and C. parapsilosis exhibited proteinase activities. Majority of the isolates were capable of forming mature biofilms. Interestingly, the presence of serum distorted the yeast sensitivity to fluconazole, but not amphotericin B. Taken together, our findings demonstrate that CBI isolates of Candida have the potential to express to varying extent their virulence attributes (e.g., biofilm formation, hemolysin production, and proteinase activity) and these, together with perturbations in their antifungal sensitivity in the presence of serum, may contribute to treatment complication in candidemia. The effect of serum on antifungal activity warrants further investigations, as it has direct clinical relevance to the treatment outcome in subjects with candidemia.

Exploring the thiazole scaffold for the identification of new agents for the treatment of fluconazole resistant Candida

Cyclohexyliden- and 2-methylcyclohexyliden-hydrazo-4-arylthiazoles were synthesized and tested as antifungal agents. All compounds exhibited minimal inhibitory concentration (MIC) values comparable with those of fluconazole (FLC). Moreover, some compounds showed fungicidal activity at low concentration. Worth noting five out of nine compounds were active towards Candida albicans 25 FLC resistant isolated from clinical specimens. The cellular toxicity was evaluated and none of the compounds is toxic at the MIC. On the basis of our data we can conclude that these derivatives are promising agents for the treatment of resistant C. albicans.

Systemic antifungal therapy for proven or suspected invasive candidiasis: the AmarCAND 2 study

Background

In the context of recent guidelines on invasive candidiasis (IC), how French intensive care units (ICUs) are managing IC?

Methods

This is a prospective observational multicenter cohort study. During 1 year (2012–2013), 87 French ICUs enrolled consecutive patients with suspected or proven IC (SIC or PIC) and receiving systemic antifungal therapy (SAT). Data were collected up to 28 days after inclusion.

Results

We studied 835 patients, 291 with PIC and 544 with SIC. At SAT initiation, patients with SIC were significantly more severe (SAPS II 50.1 ± 18.7 vs. 46.2 ± 18.0). Severe sepsis or septic shock prompted to initiate empiric SAT in 70 % of SIC. Within 4 days in median, the initial SAT was modified in 49 % of patients with PIC vs. 33 % patients with SIC. Modifications were most often motivated by mycological results, and de-escalation was the most frequent change. Regarding compliance to IC management guidelines, echinocandin was used for 182 (62.5 %) patients with PIC, and 287 (52.7 %) of those with SIC; central venous catheter was removed in 87 (54.3 %) of patients with candidaemia, and 43 of the remaining patients received echinocandin; and de-escalation was undertaken after 5 days of SAT in 142 patients, after 10 days in 13 patients. As 20.6 % of SIC were secondarily documented, 403/835 (48 %) patients had finally a proven IC. Candida albicans was the main pathogen (65.3 %), then Candida glabrata (15.9 %). The 28-day mortality rates were 40.0 % in candidaemia, 25.4 % in cIAI, and 26.7 % in deep-seated candidiasis. In the overall population of patients with proven IC, four independent prognostic factors were identified: immunosuppression (Odds Ratio (OR) = 1.977: 1.03–3.794 95 % confidence interval (CI), p = 0.04), age (OR = 1.035; 1.017–1.053 95 % CI; p < 0.001), SAPS >46 on ICU admission (OR = 2.894; 1.81–4.626 95 % CI; p < 0.001), and surgery just before or during ICU stay (OR = 0.473; 0.29–0.77 95 % CI; p < 0.001).

Conclusion

When SAT is initiated in French ICUs, the IC is ultimately proven for 48 % of patients. Empiric SAT is initiated in severely ill ICU patients. The initial SAT is often adapted, with de-escalation to fluconazole when possible. Mortality rate remains high.

Electronic supplementary material

The online version of this article (doi:10.1186/s13613-015-0103-7) contains supplementary material, which is available to authorized users.

Antifungal Susceptibility Patterns of Candida Species Recovered from Endotracheal Tube in an Intensive Care Unit

Aims. Biofilms formed by Candida species which associated with drastically enhanced resistance against most antimicrobial agents. The aim of this study was to identify and determine the antifungal susceptibility pattern of Candida species isolated from endotracheal tubes from ICU patients. Methods. One hundred forty ICU patients with tracheal tubes who were intubated and mechanically ventilated were surveyed for endotracheal tube biofilms. Samples were processed for quantitative microbial culture. Yeast isolates were identified to the species level based on morphological characteristics and their identity was confirmed by PCR-RFLP. Antifungal susceptibility testing was determined according to CLSI document (M27-A3). Results. Ninety-five strains of Candida were obtained from endotracheal tubes of which C. albicans (n = 34; 35.7%) was the most frequently isolated species followed by other species which included C. glabrata (n = 24; 25.2%), C. parapsilosis (n = 16; 16.8%), C. tropicalis (n = 12; 12.6%), and C. krusei (n = 9; 9.4%). The resulting MIC90 for all Candida species were in increasing order as follows: caspofungin (0.5 μg/mL); amphotericin B (2 μg/mL); voriconazole (8.8 μg/mL); itraconazole (16 μg/mL); and fluconazole (64 μg/mL). Conclusion. Candida species recovered from endotracheal tube are the most susceptible to caspofungin.

Posttreatment Antifungal Resistance among Colonizing Candida Isolates in Candidemia Patients: Results from a Systematic Multicenter Study

The prevalence of intrinsic and acquired resistance among colonizing Candida isolates from patients after candidemia was investigated systematically in a 1-year nationwide study. Patients were treated at the discretion of the treating physician. Oral swabs were obtained after treatment. Species distributions and MIC data were investigated for blood and posttreatment oral isolates from patients exposed to either azoles or echinocandins for <7 or ≥ 7 days. Species identification was confirmed using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and internal transcribed spacer (ITS) sequencing, susceptibility was examined by EUCAST EDef 7.2 methodology, echinocandin resistance was examined by FKS sequencing, and genetic relatedness was examined by multilocus sequence typing (MLST). One hundred ninety-three episodes provided 205 blood and 220 oral isolates. MLST analysis demonstrated a genetic relationship for 90% of all paired blood and oral isolates. Patients exposed to azoles for ≥ 7 days (n = 93) had a significantly larger proportion of species intrinsically less susceptible to azoles (particularly Candida glabrata) among oral isolates than among initial blood isolates (36.6% versus 12.9%; P < 0.001). A similar shift toward species less susceptible to echinocandins among 85 patients exposed to echinocandins for ≥ 7 days was not observed (4.8% of oral isolates versus 3.2% of blood isolates; P > 0.5). Acquired resistance in Candida albicans was rare (<5%). However, acquired resistance to fluconazole (29.4%; P < 0.05) and anidulafungin (21.6%; P < 0.05) was common in C. glabrata isolates from patients exposed to either azoles or echinocandins. Our findings suggest that the colonizing mucosal microbiota may be an unrecognized reservoir of resistant Candida species, especially C. glabrata, following treatment for candidemia. The resistance rates were high, raising concern in general for patients exposed to antifungal drugs.

Secular Trends in Utilization of Critical Care Services Among Candidemia-Associated Hospitalizations: A Population-Based Cohort Study

Background

The incidence of candidemia continues to rise in recent years. Candidemic patients often require care in an intensive care unit (ICU) and can consume substantial resources. However, there are no contemporary longitudinal population-level data on the incidence patterns of ICU utilization among patients with candidemia in the United States.

Methods

The Texas Inpatient Public Use Data File was used to identify hospitalized patients aged ≥ 18 years for the years 2001 - 2010. Hospitalizations with candidemia were identified by presence of an International Classification of Diseases, Ninth Revision, Clinical Modification Code 112.5. The annual rates of ICU admission among candidemia hospitalizations were examined. The annual incidence of candidemia hospitalizations with admission to ICU (C-ICU) was evaluated using the United States Census data, and was also benchmarked against the number of all hospitalizations and hospitalizations with ICU admission, overall and for age-specific strata.

Results

There were 11,544 hospitalizations with candidemia, including 7,552 (65.4%) with C-ICU. Between 2001 and 2010, the rate of C-ICU among hospitalizations with candidemia increased from 60.2% to 68.0%, and the incidence of C-ICU increased by 91%, rising from 2.73 to 5.21 per 100,000 population. When benchmarked against hospital admissions and ICU admissions, the following changes were noted between 2001 and 2010 in the incidence of C-ICU: 1.61 vs. 3.34 per 10,000 hospitalizations, and 8.33 vs. 13.77 per 10,000 hospitalizations with ICU admission. The incidence of C-ICU rose rapidly during the first half of the last decade, while plateauing during the remainder of study period. There has been marked difference in the rate of rise in the incidence of C-ICU among examined age strata, being highest among the 18 - 44 year group.

Conclusions

ICU care occurred in the majority of candidemia hospitalizations. The incidence of C-ICU rose nearly two-fold during study period, but the rise plateaued during the second half of the last decade. Substantial heterogeneity was noted in the rate of rise in the incidence of C-ICU across examined age groups. Further study in other populations is required to corroborate our findings and examine the sources of the observed trends.

Demonstration of Therapeutic Equivalence of Fluconazole Generic Products in the Neutropenic Mouse Model of Disseminated Candidiasis

Some generics of antibacterials fail therapeutic equivalence despite being pharmaceutical equivalents of their innovators, but data are scarce with antifungals. We used the neutropenic mice model of disseminated candidiasis to challenge the therapeutic equivalence of three generic products of fluconazole compared with the innovator in terms of concentration of the active pharmaceutical ingredient, analytical chemistry (liquid chromatography/mass spectrometry), in vitro susceptibility testing, single-dose serum pharmacokinetics in infected mice, and in vivo pharmacodynamics. Neutropenic, five week-old, murine pathogen free male mice of the strain Udea:ICR(CD-2) were injected in the tail vein with Candida albicans GRP-0144 (MIC = 0.25 mg/L) or Candida albicans CIB-19177 (MIC = 4 mg/L). Subcutaneous therapy with fluconazole (generics or innovator) and sterile saline (untreated controls) started 2 h after infection and ended 24 h later, with doses ranging from no effect to maximal effect (1 to 128 mg/kg per day) divided every 3 or 6 hours. The Hill’s model was fitted to the data by nonlinear regression, and results from each group compared by curve fitting analysis. All products were identical in terms of concentration, chromatographic and spectrographic profiles, MICs, mouse pharmacokinetics, and in vivo pharmacodynamic parameters. In conclusion, the generic products studied were pharmaceutically and therapeutically equivalent to the innovator of fluconazole.

Impact of antifungal prescription on relative distribution and susceptibility of Candida spp. - Trends over 10 years

INTRODUCTION

The incidence of Candida spp. infections is worrisome, particularly in critically ill patients. Previous reports suggested that increasing use of antifungal therapy might affect resistance profiles of invasive strains. The study objective was to describe the distribution resistance profile of Candida spp. strains, and to correlate it with antifungal consumptions within one ICU.

METHOD

Antifungal drug consumption was measured as the number of defined daily doses per 1000 hospital days. The distribution of Candida spp. over a 10 year period 2004-2013 and the MICs of antifungal drugs over 2007-2013 were determined. Time series analyses were performed.

RESULTS

Of 2403 identified Candida spp. from 5360 patients, Candida albicans predominated (53.1%), followed by Candida glabrata (16.2%), Candida parapsilosis (7.9%) and Candida tropicalis (7.5%). C. parapsilosis increased from 5.7% in 2004 to 8.4% in 2013 (P = 0.02). The increase in caspofungin use is correlated with the increase in caspofungin MICs of C. parapsilosis (P = 0.01), C. glabrata (P = 0.001) and C. albicans (P = 0.02). Polyenes consumption correlated with an increase in amphotericin B MICs of C. glabrata (P = 0.04).

CONCLUSION

Previous history of antifungal prescription within an ICU influences Candida species distribution and susceptibility profile to antifungal agents. The significant selective pressure exerted by caspofungin and amphotericin B on C. glabrata is a concern.

Biofilm formation is a risk factor for mortality in patients with Candida albicans bloodstream infection-Scotland, 2012-2013

Bloodstream infections caused by Candida species remain a significant cause of morbidity and mortality in hospitalized patients. Biofilm formation by Candida species is an important virulence factor for disease pathogenesis. A prospective analysis of patients with Candida bloodstream infection (n = 217) in Scotland (2012–2013) was performed to assess the risk factors associated with patient mortality, in particular the impact of biofilm formation. Candida bloodstream isolates (n = 280) and clinical records for 157 patients were collected through 11 different health boards across Scotland. Biofilm formation by clinical isolates was assessed in vitro with standard biomass assays. The role of biofilm phenotype on treatment efficacy was also evaluated in vitro by treating preformed biofilms with fixed concentrations of different classes of antifungal. Available mortality data for 134 patients showed that the 30-day candidaemia case mortality rate was 41%, with predisposing factors including patient age and catheter removal. Multivariate Cox regression survival analysis for 42 patients showed a significantly higher mortality rate for Candida albicans infection than for Candida glabrata infection. Biofilm-forming ability was significantly associated with C. albicans mortality (34 patients). Finally, in vitro antifungal sensitivity testing showed that low biofilm formers and high biofilm formers were differentially affected by azoles and echinocandins, but not by polyenes. This study provides further evidence that the biofilm phenotype represents a significant clinical entity, and that isolates with this phenotype differentially respond to antifungal therapy in vitro. Collectively, these findings show that greater clinical understanding is required with respect to Candida biofilm infections, and the implications of isolate heterogeneity.

Echinocandin resistance: an emerging clinical problem?

PURPOSE OF REVIEW

Echinocandin resistance in Candida is a great concern, as the echinocandin drugs are recommended as first-line therapy for patients with invasive candidiasis. Here, we review recent advances in our understanding of the epidemiology, underlying mechanisms, methods for detection and clinical implications.

RECENT FINDINGS

Echinocandin resistance has emerged over the recent years. It has been found in most clinically relevant Candida spp., but is most common in C. glabrata with rates exceeding 10% at selected institutions. It is most commonly detected after 3-4 weeks of treatment and is associated with a dismal outcome. An extensive list of mutations in hot spot regions of the genes encoding the target has been characterized and associated with species and drug-specific loss of susceptibility. The updated antifungal susceptibility testing reference methods identify echinocandin-resistant isolates reliably, although the performance of commercial tests is somewhat more variable. Alternative technologies are being developed, including molecular detection and matrix-assisted laser desorption ionization-time of flight.

SUMMARY

Echinocandin resistance is increasingly encountered and its occurrence makes susceptibility testing essential, particularly in patients with prior exposure. The further development of rapid and user-friendly commercially available susceptibility platforms is warranted. Antifungal stewardship is important in order to minimize unnecessary selection pressure.

Combination of fluconazole with silver nanoparticles produced by Fusarium oxysporum improves antifungal effect against planktonic cells and biofilm of drug-resistant Candida albicans

Silver nanoparticles (AgNPs) have been extensively studied because of their anti-microbial potential. Here, we evaluated the effect of biologically synthesized silver nanoparticles (AgNPbio) alone and in combination with fluconazole (FLC) against planktonic cells and biofilms of FLC-resistant Candida albicans AgNPbio exhibited a fungicidal effect, with a minimal inhibitory concentration (MIC) and fungicidal concentration ranging from 2.17 to 4.35 μg/ml. The combination of AgNPbio and FLC reduced the MIC of FLC around 16 to 64 times against planktonic cells of allC. albicans There was no significant inhibitory effect of AgNPbio on biofilm cells. However, FLC combined with AgNPbio caused a significant dose-dependent decrease in the viability of both initial and mature biofilm. All concentrations of AgNPbio, alone or in combination with FLC, were not cytotoxic to mammalian cells.The results highlight the effectiveness of the combination of AgNPbio with FLC against FLC-resistant C. albicans.

Twenty-two years of candidaemia surveillance: results from a Norwegian national study

Several studies have reported an increased incidence of candidaemia and a redistribution of species, with a decrease in the number of Candida albicans isolates. In Norway, a prospective, national surveillance study of candidaemia has been ongoing since 1991. Data from the period 1991-2003 have been published previously. The aim of this study was to follow up the incidence, species distribution and antifungal susceptibility of Candida species isolates from blood cultures in the period 2004-2012, and compare them with the corresponding findings from the period 1991-2003. Blood culture isolates of Candida species from all medical microbiological laboratories in Norway were identified and susceptibility tested at the Norwegian Mycological Reference Laboratory. A total of 1724 isolates were recovered from 1653 patients in the period 2004-2012. Comparison of the two periods showed that the average incidence of candidaemia episodes per 100 000 inhabitants increased from 2.4 (1991-2003) to 3.9 (2004-2012). The increase in incidence in the latter period was significantly higher in patients aged >40 years (p 0.001), and a marked increase was observed in patients aged >60 years (p < 0.001). In conclusion, the average incidence in Norway over a period of 22 years modestly increased from 2.4 to 3.9 per 100,000 inhabitants, this being mainly accounted for by candidaemia in the elderly. The species distribution was stable, and the rate of acquired resistance was low.

Multidrug-resistant Trichosporon: an unusual fungal sepsis in preterm neonates

We report a cluster of three extremely-low birth weight (ELBW), preterm neonates who developed late-onset sepsis (LOS) by Trichosporon asahii within a span of 1 week period. Two of these cases had the initial diagnosis of respiratory distress syndrome and the third one was admitted for low birth weight and prematurity. Initial sepsis screen was negative and blood culture was sterile in all. Late-onset sepsis was developed after the first week of life and the presenting features were lethargy, feeding intolerance, bleeding manifestations, positive sepsis screen and severe thrombocytopaenia. The isolates were sensitive to voriconazole but resistant to both amphotericin-B and fluconazole on all occasions. All the infants were treated with liposomal amphotericin-B before the availability of culture reports but the clinical deterioration was rapid and all three neonates succumbed to death before we could procure voriconazole. The source of the outbreak could not be identified from multiple surface cultures from the unit and screening of the health care staffs. We emphasise the need for high index of suspicion for unusual fungal pathogens, resistant to conventional antifungal drugs while treating preterm neonates with LOS.

Biliary amphotericin B pharmacokinetics and pharmacodynamics in critically ill liver transplant recipients receiving treatment with amphotericin B lipid formulations

Fungal cholangitis is a potentially life-threatening condition. As amphotericin B (AmB) has a broad antimycotic spectrum, in this study its biliary penetration and activity was determined in two patients treated with liposomal AmB (L-AmB) and in one patient receiving AmB colloidal dispersion (ABCD). Biliary and plasma AmB levels were quantified by high-performance liquid chromatography after purification by solid-phase extraction. For assessment of biliary AmB activity, isolates of Candida albicans, Candida tropicalis, Candida glabrata and Candida krusei were incubated in porcine bile at AmB concentrations of 0.025-5.00 mg/L. In addition, patient bile samples retrieved for AmB quantification were inoculated with the same Candida strains. Biliary AmB concentrations were lower and displayed a slower rise and decline than plasma levels. The highest penetration ratio, as expressed by the ratio between the area under the AmB concentration-time curve in bile and plasma (liberated AmB) over the sampling period (AUC0-n bile/AUC0-n LI plasma), was 0.28. Proliferation of C. albicans and C. tropicalis in bile was similar to that in culture medium, whereas growth of C. glabrata was diminished and proliferation of C. krusei was absent in bile. In comparison with culture medium, AmB activity decreased in spiked porcine bile. In all but one patient bile sample, fungal growth was delayed or lacking even when AmB was not detectable. However, no fungicidal effect was observed in patient bile at AmB concentrations up to 1.28 mg/L. Thus, a reliable response of fungal cholangitis to treatment with L-AmB or ABCD cannot be anticipated.

Are the Conventional Commercial Yeast Identification Methods Still Helpful in the Era of New Clinical Microbiology Diagnostics? A Meta-Analysis of Their Accuracy

Accurate identification of pathogenic species is important for early appropriate patient management, but growing diversity of infectious species/strains makes the identification of clinical yeasts increasingly difficult. Among conventional methods that are commercially available, the API ID32C, AuxaColor, and Vitek 2 systems are currently the most used systems in routine clinical microbiology. We performed a systematic review and meta-analysis to estimate and to compare the accuracy of the three systems, in order to assess whether they are still of value for the species-level identification of medically relevant yeasts. After adopting rigorous selection criteria, we included 26 published studies involving Candida and non-Candida yeasts that were tested with the API ID32C (674 isolates), AuxaColor (1,740 isolates), and Vitek 2 (2,853 isolates) systems. The random-effects pooled identification ratios at the species level were 0.89 (95% confidence interval [CI], 0.80 to 0.95) for the API ID32C system, 0.89 (95% CI, 0.83 to 0.93) for the AuxaColor system, and 0.93 (95% CI, 0.89 to 0.96) for the Vitek 2 system (P for heterogeneity, 0.255). Overall, the accuracy of studies using phenotypic analysis-based comparison methods was comparable to that of studies using molecular analysis-based comparison methods. Subanalysis of studies conducted on Candida yeasts showed that the Vitek 2 system was significantly more accurate (pooled ratio, 0.94 [95% CI, 0.85 to 0.99]) than the API ID32C system (pooled ratio, 0.84 [95% CI, 0.61 to 0.99]) and the AuxaColor system (pooled ratio, 0.76 [95% CI, 0.67 to 0.84]) with respect to uncommon species (P for heterogeneity, <0.05). Subanalysis of studies conducted on non-Candida yeasts (i.e., Cryptococcus, Rhodotorula, Saccharomyces, and Trichosporon) revealed pooled identification accuracies of ≥98% for the Vitek 2, API ID32C (excluding Cryptococcus), and AuxaColor (only Rhodotorula) systems, with significant low or null levels of heterogeneity (P > 0.05). Nonetheless, clinical microbiologists should reconsider the usefulness of these systems, particularly in light of new diagnostic tools such as matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry, which allow for considerably shortened turnaround times and/or avoid the requirement for additional tests for species identity confirmation.

Tipping the balance both ways: drug resistance and virulence in Candida glabrata

Among existing fungal pathogens, Candida glabrata is outstanding in its capacity to rapidly develop resistance to currently used antifungal agents. Resistance to the class of azoles, which are still widely used agents, varies in proportion (from 5 to 20%) depending on geographical area. Moreover, resistance to the class of echinocandins, which was introduced in the late 1990s, is rising in several institutions. The recent emergence of isolates with acquired resistance to both classes of agents is a major concern since alternative therapeutic options are scarce. Although considered less pathogenic than C. albicans, C. glabrata has still evolved specific virulence traits enabling its survival and propagation in colonized and infected hosts. Development of drug resistance is usually associated with fitness costs, and this notion is documented across several microbial species. Interestingly, azole resistance in C. glabrata has revealed the opposite. Experimental models of infection showed enhanced virulence of azole-resistant isolates. Moreover, azole resistance could be associated with specific changes in adherence properties to epithelial cells or innate immunity cells (macrophages), both of which contribute to virulence changes. Here we will summarize the current knowledge on C. glabrata drug resistance and also discuss the consequences of drug resistance acquisition on the balance between C. glabrata and its hosts.

Isavuconazole, micafungin, and 8 comparator antifungal agents' susceptibility profiles for common and uncommon opportunistic fungi collected in 2013: temporal analysis of antifungal drug resistance using CLSI species-specific clinical breakpoints and proposed epidemiological cutoff values

The in vitro activities of isavuconazole, micafungin, and 8 comparator antifungal agents were determined for 1613 clinical isolates of fungi (1320 isolates of Candida spp., 155 of Aspergillus spp., 103 of non-Candida yeasts, and 35 non-Aspergillus molds) collected during a global survey conducted in 2013. The vast majority of the isolates of the 21 different species of Candida, with the exception of Candida glabrata (MIC90, 2 μg/mL), Candida krusei (MIC90, 1 μg/mL), and Candida guilliermondii (MIC90, 8 μg/mL), were inhibited by ≤0.25 μg/mL of isavuconazole. C. glabrata and C. krusei were largely inhibited by ≤1 μg/mL of isavuconazole. Resistance to fluconazole was seen in 0.5% of Candida albicans isolates, 11.1% of C. glabrata isolates, 2.5% of Candida parapsilosis isolates, 4.5% of Candida tropicalis isolates, and 20.0% of C. guilliermondii isolates. Resistance to the echinocandins was restricted to C. glabrata (1.3-2.1%) and C. tropicalis (0.9-1.8%). All agents except for the echinocandins were active against 69 Cryptococcus neoformans isolates, and the triazoles, including isavuconazole, were active against the other yeasts. Both the mold active triazoles as well as the echinocandins were active against 155 Aspergillus spp. isolates belonging to 10 species/species complex. In general, there was low resistance levels to the available systemically active antifungal agents in a large, contemporary (2013), global collection of molecularly characterized yeasts and molds. Resistance to azoles and echinocandins was most prominent among isolates of C. glabrata, C. tropicalis, and C. guilliermondii.

Antifungal susceptibility profiles of bloodstream yeast isolates by Sensititre YeastOne over nine years at a large Italian teaching hospital

Sensititre YeastOne (SYO) is an affordable alternative to the Clinical and Laboratory Standards Institute (CLSI) reference method for antifungal susceptibility testing. In this study, the MICs of yeast isolates from 1,214 bloodstream infection episodes, generated by SYO during hospital laboratory activity (January 2005 to December 2013), were reanalyzed using current CLSI clinical breakpoints/epidemiological cutoff values to assign susceptibility (or the wild-type [WT] phenotype) to systemic antifungal agents. Excluding Candida albicans (57.4% of all isolates [n = 1,250]), the most predominant species were Candida parapsilosis complex (20.9%), Candida tropicalis (8.2%), Candida glabrata (6.4%), Candida guilliermondii (1.6%), and Candida krusei (1.3%). Among the non-Candida species (1.9%), 7 were Cryptococcus neoformans and 17 were other species, mainly Rhodotorula species. Over 97% of Candida isolates were susceptible (WT phenotype) to amphotericin B and flucytosine. Rates of susceptibility (WT phenotype) to fluconazole, itraconazole, and voriconazole were 98.7% in C. albicans, 92.3% in the C. parapsilosis complex, 96.1% in C. tropicalis, 92.5% in C. glabrata, 100% in C. guilliermondii, and 100% (excluding fluconazole) in C. krusei. The fluconazole-resistant isolates consisted of 6 C. parapsilosis complex isolates, 3 C. glabrata isolates, 2 C. albicans isolates, 2 C. tropicalis isolates, and 1 Candida lusitaniae isolate. Of the non-Candida isolates, 2 C. neoformans isolates had the non-WT phenotype for susceptibility to fluconazole, whereas Rhodotorula isolates had elevated azole MICs. Overall, 99.7% to 99.8% of Candida isolates were susceptible (WT phenotype) to echinocandins, but 3 isolates were nonsusceptible (either intermediate or resistant) to caspofungin (C. albicans, C. guilliermondii, and C. krusei), anidulafungin (C. albicans and C. guilliermondii), and micafungin (C. albicans). However, when the intrinsically resistant non-Candida isolates were included, the rate of echinocandin nonsusceptibility reached 1.8%. In summary, the SYO method proved to be able to detect yeast species showing antifungal resistance or reduced susceptibility.

Ibuprofen potentiates the in vivo antifungal activity of fluconazole against Candida albicans murine infection

Candida albicans is the most prevalent cause of fungemia worldwide. Its ability to develop resistance in patients receiving azole antifungal therapy is well documented. In a murine model of systemic infection, we show that ibuprofen potentiates fluconazole antifungal activity against a fluconazole-resistant strain, drastically reducing the fungal burden and morbidity. The therapeutic combination of fluconazole with ibuprofen may constitute a new approach for the management of antifungal therapeutics to reverse the resistance conferred by efflux pump overexpression.

Epidemiology, management, and outcome of invasive fungal disease in patients undergoing hematopoietic stem cell transplantation in China: a multicenter prospective observational study

The China Assessment of Antifungal Therapy in Hematological Disease study, the first large-scale observational study of invasive fungal disease (IFD) in China, enrolled 1401 patients undergoing hematopoietic stem cell transplantation (HSCT) (75.2% allogeneic and 24.8% autologous) at 31 hospitals across China. The overall incidence of proven or probable IFD was 7.7% (108 of 1401); another 266 cases (19.0%) were possible IFD. After allogeneic or autologous HSCT, the incidence of proven/probable IFD was 8.9% (94 of 1053) and 4.0% (14 of 348), respectively. Some cases (14 of 108) developed during conditioning before transplantation. The cumulative incidence of proven/probable IFD increased steeply in the first month after transplantation and after 6 months, the incidence was significantly higher in allogeneic than it was in autologous transplant recipients (9.2% versus 3.5%; P = .001) and when stem cells were derived from cord blood or bone marrow and peripheral blood (P = .02 versus other sources). Independent risk factors for proven/probable IFD in allogeneic HSCT were diabetes, HLA-matched unrelated donor, prolonged severe neutropenia (absolute neutrophil count > 500/mm(3) for >14 days), and immunosuppressants (odds ratio, 2.0 to 3.4 for all). Antifungal prophylaxis was independently protective (P = .01). Previous IFD and prolonged severe neutropenia were significant independent risk factors among autologous transplantation patients (P < .01, P = .04, respectively). In total, 1175 (83.9%) patients received antifungal prophylaxis (91.6% triazoles) and 514 (36.7%) were treated in the hospital with therapeutic antifungals (89.1% triazoles; median 27 days). Empirical, pre-emptive, and targeted antifungals were used in 82.3%, 13.6%, and 4.1% of cases, respectively. Overall mortality (13.4%; 188 deaths) was markedly higher in patients with proven (5 of 16; 31.3%), probable (20 of 92; 21.7%), or possible (61 of 266; 22.9%) IFD; allogeneic (171 of 1053; 16.2%) rather than autologous (17 of 348; 4.9%) HSCT and was significantly higher in patients receiving pre-emptive (18.6%) rather than empirical (6.1%) or targeted (9.5%) antifungal therapy (P = .002). Improvements in the selection and timing of prophylactic antifungals would be welcome. Health care providers should remain alert to the increased risk of IFD and associated mortality in allogeneic HSCT recipients and the ongoing risk of IFD even after discharge from the hospital.

Antifungal susceptibilities of bloodstream isolates of Candida species from nine hospitals in Korea: application of new antifungal breakpoints and relationship to antifungal usage

We applied the new clinical breakpoints (CBPs) of the Clinical and Laboratory Standards Institute (CLSI) to a multicenter study to determine the antifungal susceptibility of bloodstream infection (BSI) isolates of Candida species in Korea, and determined the relationship between the frequency of antifungal-resistant Candida BSI isolates and antifungal use at hospitals. Four hundred and fifty BSI isolates of Candida species were collected over a 1-year period in 2011 from nine hospitals. The susceptibilities of the isolates to four antifungal agents were determined using the CLSI M27 broth microdilution method. By applying the species-specific CBPs, non-susceptibility to fluconazole was found in 16.4% (70/428) of isolates, comprising 2.6% resistant and 13.8% susceptible-dose dependent isolates. However, non-susceptibility to voriconazole, caspofungin, or micafungin was found in 0% (0/370), 0% (0/437), or 0.5% (2/437) of the Candida BSI isolates, respectively. Of the 450 isolates, 72 (16.0%) showed decreased susceptibility to fluconazole [minimum inhibitory concentration (MIC) ≥4 μg/ml]. The total usage of systemic antifungals varied considerably among the hospitals, ranging from 190.0 to 7.7 defined daily dose per 1,000 patient days, and fluconazole was the most commonly prescribed agent (46.3%). By Spearman’s correlation analysis, fluconazole usage did not show a significant correlation with the percentage of fluconazole resistant isolates at hospitals. However, fluconazole usage was significantly correlated with the percentage of fluconazole non-susceptible isolates (r = 0.733; P = 0.025) or the percentage of isolates with decreased susceptibility to fluconazole (MIC ≥4 μg/ml) (r = 0.700; P = 0.036) at hospitals. Our work represents the first South Korean multicenter study demonstrating an association between antifungal use and antifungal resistance among BSI isolates of Candida at hospitals using the new CBPs of the CLSI.

Epidemiology of echinocandin resistance in Candida

Echinocandins are the newest antifungal agents approved for use in treating Candida infections in the US. They act by interfering with 1,3-β-D-glucan synthase and therefore disrupt cell wall production and lead to Candida cell death. There is no intrinsic resistance to echinocandins among Candida species, and isolates from historic collections archived before the release of the echinocandins show no resistance. Resistance to the echinocandins remains low among most Candida species and ranges overall from 0-1%. Among isolates of Candida glabrata, the proportion of resistant isolates is higher and has been reported to be as high as 13.5% in at least one hospital. Antifungal resistance is due to specific amino acid mutations in the Fksp subunit(s) of the 1,3-β-D-glucan synthase protein which are localized to one of two hotspots. These mutations are being recognized in isolates from patients who have failed echinocandin therapy, and often lead to a poor outcome. While the future looks bright for the echinocandins against most Candida species, C. glabrata remains a species of concern and resistance rates of C. glabrata to the echinocandins should be monitored closely.

Comparison of the probability of target attainment of anidulafungin against Candida spp. in patients with acute leukaemia

This study aimed to investigate the probability of target attainment (PTA) of various anidulafungin dosing regimens against Candida spp. in patients with acute leukaemia. A Monte Carlo simulation was performed using a previously published population pharmacokinetic model. The following dosing scenarios were evaluated: 200 mg loading dose (LD) on Day 1 then 100 mg daily (manufacturer's recommended dosing regimen); 200 mg LD on Day 1 then 100 mg every 48 h (q48 h); and 200 mg q48 h, 200 mg every 72 h (q72 h) and 300 mg q72 h. For each dosing regimen, free drug concentrations were calculated to evaluate the effect of 99% protein binding. The PTA at various pharmacodynamic (PD) targets was determined as the percentage of subjects who achieved a free drug area under the plasma concentration-time curve over the minimum inhibitory concentration ratio (ƒAUC/MIC) or a free drug maximum plasma concentration over the minimum inhibitory concentration ratio (ƒC(max)/MIC) above the PD targets. PTA expectation values were then calculated for each dosing regimen. The currently recommended dosing regimen of anidulafungin was not optimal for invasive candidiasis in patients with acute leukaemia. Alternate dosing strategies with higher doses and extended dosing intervals (intermittent dosing) achieved better target attainment. This is the first study to optimise therapy with anidulafungin using Monte Carlo simulation. These results provide a rationale in support of future clinical investigation of intermittent dosing of anidulafungin.

Worrisome trends in incidence and mortality of candidemia in intensive care units (Paris area, 2002-2010)

Purpose

To analyze trends in incidence and mortality of candidemia in intensive care units (ICUs) vs. non-ICU hospitalized patients and to determine risk factors for infection by specific species and for death.

Methods

Active hospital-based surveillance program of incident episodes of candidemia due to common species in 24 tertiary care hospitals in the Paris area, France between October 2002 and September 2010.

Results

Among 2,507 adult cases included, 2,571 Candida isolates were collected and species were C. albicans (56 %), C. glabrata (18.6 %), C. parapsilosis (11.5 %), C. tropicalis (9.3 %), C. krusei (2.9 %), and C. kefyr (1.8 %). Candidemia occurred in ICU in 1,206 patients (48.1 %). When comparing ICU vs. non-ICU patients, the former had significantly more frequent surgery during the past 30 days, were more often preexposed to fluconazole and treated with echinocandin, and were less frequently infected with C. parapsilosis. Risk factors and age remained unchanged during the study period. A significant increased incidence in the overall population and ICU was found. The odds of being infected with a given species in ICU was influenced by risk factors and preexposure to fluconazole and caspofungin. Echinocandins initial therapy increased over time in ICU (4.6 % first year of study, to 48.5 % last year of study, p < 0.0001). ICU patients had a higher day-30 death rate than non-ICU patients (odds ratio [OR] 2.12; 95 % confidence interval [CI] 1.66–2.72; p < 0.0001). The day-30 and early (<day 8) death rates increased over time in ICU (from 41.5 % the first to 56.9 % the last year of study (p = 0.001) and 28.7–38.8 % (p = 0.0292), respectively). Independent risk factors for day-30 death in ICU were age, arterial catheter, Candida species, preexposure to caspofungin, and lack of antifungal therapy at the time of blood cultures results (p < 0.05).

Conclusions

The availability of new antifungals and the publication of numerous guidelines did not prevent an increase of candidemia and death in ICU patients in the Paris area.

Activity of echinocandins and triazoles against a contemporary (2012) worldwide collection of yeast and moulds collected from invasive infections

In this study, 1717 fungal clinical isolates causing invasive fungal infections were evaluated against nine antifungal agents using Clinical and Laboratory Standards Institute (CLSI) reference broth microdilution methods. The isolates comprised 1487 Candida spp., 109 Aspergillus spp., 86 non-Candida yeasts (including 52 isolates of Cryptococcus neoformans) and 35 rare moulds obtained during 2012 from 72 hospitals worldwide. Echinocandin resistance among Candida spp. was low, and resistance rates to anidulafungin, caspofungin and micafungin varied from 0.0% to 2.8% among different species. Echinocandin-resistant Candida glabrata were shown to have fks mutations (fks2 HS1 F659Y, F659del, S663F and S663P), and fluconazole resistance was also observed in those strains. One Candida krusei and one Candida dubliniensis had L701M or S645P fks1 mutations, respectively. Candida tropicalis and C. glabrata had higher fluconazole resistance rates of 6.1% and 6.9%, respectively, compared with other Candida spp. Fluconazole-resistant C. tropicalis were collected in five countries (USA, China, Germany, Belgium and Thailand). Voriconazole was active against all Candida spp., inhibiting 91.2-99.7% of isolates using species-specific breakpoints. All agents except for the echinocandins and posaconazole were active against Cr. neoformans. Triazoles were active against other yeasts [MIC90 (minimum inhibitory concentration encompassing 90% of isolates tested), 2μg/mL]. The echinocandins and the mould-active triazoles were active against Aspergillus [MIC/MEC90 (minimum effective concentration encompassing 90% of isolates tested) range, 0.015-2μg/mL], but the activity of these agents was limited against uncommon mould species (MIC/MEC90 range, 4μg/mL to >16μg/mL).

Species distribution and in vitro antifungal susceptibility profiles of yeast isolates from invasive infections during a Portuguese multicenter survey

This is the first Portuguese multicenter observational and descriptive study that provides insights on the species distribution and susceptibility profiles of yeast isolates from fungemia episodes. Ten district hospitals across Portugal contributed by collecting yeast isolates from blood cultures and answering questionnaires concerning patients' data during a 12-month period. Molecular identification of cryptic species of Candida parapsilosis and C. glabrata complex was performed. The susceptibility profile of each isolate, considering eight of the most often used antifungals, was determined. Both Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) protocols were applied. The incidence of 240 episodes of fungemia was 0.88/1,000 admissions. Fifteen different species were found, with C. albicans (40 %) being the most prevalent, followed by C. parapsilosis (23 %) and C. glabrata (13 %). Most isolates were recovered from patients admitted to surgical wards or intensive care units, with 57 % being males and 32 % aged between 41 and 60 years. For both the CLSI and EUCAST protocols, the overall susceptibility rates ranged from 74 to 97 % for echinocandins and from 84 to 98 % for azoles. Important resistance rate discrepancies between protocols were observed in C. albicans and C. glabrata for echinocandins and in C. parapsilosis and C. tropicalis for azoles. Death associated with fungemia occurred in 25 % of the cases, with more than half of C. glabrata infections being fatal. The great number of Candida non-albicans is noteworthy despite a relatively low antifungal resistance rate. Studies like this are essential in order to improve empirical treatment guidelines.

Isavuconazole and nine comparator antifungal susceptibility profiles for common and uncommon Candida species collected in 2012: application of new CLSI clinical breakpoints and epidemiological cutoff values

The in vitro activity of isavuconazole and nine antifungal comparator agents was assessed using reference broth microdilution methods against 1,421 common and uncommon species of Candida from a 2012 global survey. Isolates were identified using CHROMagar, biochemical methods and sequencing of ITS and/or 28S regions. Candida spp. were classified as either susceptible or resistant and as wild type (WT) or non-WT using CLSI clinical breakpoints or epidemiological cutoff values, respectively, for the antifungal agents. Isolates included 1,421 organisms from 21 different species of Candida. Among Candida spp., resistance to all 10 tested antifungal agents was low (0.0-7.9 %). The vast majority of each species of Candida, with the exception of Candida glabrata, Candida krusei, and Candida guilliermondii (modal MICs of 0.5 µg/ml), were inhibited by ≤0.12 µg/ml of isavuconazole (99.0 %; range 94.3 % [Candida tropicalis] to 100.0 % [Candida lusitaniae and Candida dubliniensis]). C. glabrata, C. krusei, and C. guilliermondii were largely inhibited by ≤1 µg/ml of isavuconazole (89.7, 96.9 and 92.8 %, respectively). Decreased susceptibility to isavuconazole was most prominent with C. glabrata where the modal MIC for isavuconazole was 0.5 µg/ml for those strains that were SDD to fluconazole or WT to voriconazole, and was 4 µg/ml for those that were either resistant or non-WT to fluconazole or voriconazole, respectively. In conclusion, these data document the activity of isavuconazole and generally the low resistance levels to the available antifungal agents in a large, contemporary (2012), global collection of molecularly characterized species of Candida.

Species distribution and antifungal susceptibility profile of Candida isolates from bloodstream infections in Lima, Peru

Yeast identification and in vitro susceptibility testing provide helpful information for appropriate administration of antifungal treatments; however, few reports from the Latin American region have been published. The aim of this study was to identify the species present in isolates from bloodstream infections diagnosed in nine hospitals in Lima, Peru and to determine their in vitro susceptibility to four antifungal drugs. We tested and identified 153 isolates collected between October 2009 and August 2011 using standard methods. PCR and PCR-RFLP assays were performed to distinguish Candida albicans from Candida dubliniensis and to identify species of the Candida parapsilosis and Candida glabrata complexes. Antifungal susceptibility testing for fluconazole, anidulafungin and voriconazole was performed using the CSLI M27-A3 method, and amphotericin B susceptibility was determined using the Etest method. The most frequently isolated species were: C. albicans (61; 39.9 %), C. parapsilosis (43; 28.1 %), C. tropicalis (36; 23.5%) and C. glabrata (8; 5.2 %). The overall susceptibility rates were 98.0 %, 98.7 %, 98.0 % and 97.4 % for amphotericin B, fluconazole, voriconazole and anidulafungin, respectively. No isolate was resistant to more than one drug. These results showed that the rate of resistance to four antifungal drugs was low among Candida bloodstream isolates in Lima, Peru.

Regional data analysis of Candida non-albicans strains collected in United States medical sites over a 6-year period, 2006-2011

Limited data are available on temporal and geographic variation of occurrence and antifungal resistance of non-C. albicans Candida species (non-CA-CSP) from the USA. The objective of this study was to evaluate the occurrence and antifungal resistance of 1694 isolates of non-CA-CSP collected during the period 2006-2011. Isolates were recovered in 33 hospitals located in four regions: Northcentral, North-east, South-east and West and tested using CLSI reference broth microdilution methods. Non-CA-CSP represented 55.6% of all Candida. C. glabrata was most predominant (39-42% of non-CA-CSP). Infections due to C. glabrata, C. krusei and C. dubliniensis increased over the 6 years. Anidulafungin (3.6%) and caspofungin (5.7%) resistance were prominent among C. glabrata from the North-east and West regions respectively. Resistance to micafungin was detected in 2.0% and 2.9% of C. glabrata from the West and North-east regions respectively. Echinocandin resistance was low, except for C. dubliniensis. Azole resistance was most prominent among C. glabrata from the South-east (13.6% fluconazole R) and the West (18.0%). Cross-resistance among three tested azoles was observed in C. glabrata from all regions. Whereas differences in species distribution and antifungal R varied across geographic regions, there was little evidence of temporal increase in resistance to azoles or echinocandins in the monitored non-CA-CSP.

Longer incubation times for yeast fungemia: importance for presumptive treatment

Isolation rates of Candida glabrata at ≤2 days were 8.9% and 34.8% at >2 days; for Cryptococcus neoformans, they were 0.9% and 8.6%, respectively (1741 fungemia analyzed). An incubation time >2 days supports candins as presumptive treatment for C. glabrata, keeping in mind the risk of Cryptococcus fungemia.

Epidemiology, species distribution and outcome of nosocomial Candida spp. bloodstream infection in Shanghai

Background

Yeasts, mostly Candida, are important causes of bloodstream infections (BSI), responsible for significant mortality and morbidity among hospitalized patients. The epidemiology and species distribution vary from different regions. The goals of this study were to report the current epidemiology of Candida BSI in a Shanghai Teaching Hospital and estimate the impact of appropriate antifungal therapy on the outcome.

Methods

From January 2008 to December 2012, all consecutive patients who developed Candida BSI at Ruijin University Hospital were enrolled. Underlying diseases, clinical severity, species distribution, antifungal therapy and its impact on the outcome were analyzed.

Results

A total of 121 episodes of Candida BSI were identified, with an incidence of 0.32 episodes/1,000 admissions (0.21 in 2008 and 0.42 in 2012) The proportion of candidemia caused by non-albicans species (62.8%), including C. parapsilosis (19.8%), C. tropicalis (14.9%), C. glabrata (7.4%), C. guilliermondii (5.8%), C. sake (5.0%) was higher than that of candidemia caused by C. albicans (37.2%). The overall crude 28-day mortality was 28.1% and significantly reduced with appropriate empiric antifungal therapy administered within 5 days (P = 0.006). Advanced age (OR 1.04; P = 0.014), neutropenia < 500/mm³ (OR 17.44; P < 0.001) were independent risk factors for 28-day mortality, while appropriate empiric antifungal therapy (OR 0.369; P = 0.035) was protective against 28-day mortality.

Conclusion

The epidemiology of candidemia in Shanghai differed from that observed in Western countries. Appropriate empiric antifungal therapy influenced the short-term survival.

In vitro antifungal susceptibility of Candida glabrata to caspofungin and the presence of FKS mutations correlate with treatment response in an immunocompromised murine model of invasive infection

It has been argued that the in vitro activity of caspofungin (CSP) is not a good predictor of the outcome of echinocandin treatment in vivo. We evaluated the in vitro activity of CSP and the presence of FKS mutations in the hot spot 1 (HS1) region of the FKS1 and FKS2 genes in 17 Candida glabrata strains with a wide range of MICs. The efficacy of CSP against systemic infections from each of the 17 strains was evaluated in a murine model. No HS1 mutations were found in the eight strains showing MICs for CSP of ≤ 0.5 μg/ml, but they were present in eight of the nine strains with MICs of ≥ 1 μg/ml, i.e., three in the FKS1 gene and five in the FKS2 gene. CSP was effective for treating mice infected with strains with MICs of ≤ 0.5 μg/ml, showed variable efficacy in animals challenged with strains with MICs of 1 μg/ml, and did not work in those with strains with MICs of >1 μg/ml. In addition, mutations, including one reported for the first time, were found outside the HS1 region in the FKS2 gene of six strains with different MICs, but their presence did not influence drug efficacy. The in vitro activity of CSP was compared with that of another echinocandin, anidulafungin, suggesting that the MICs of both drugs, as well as mutations in the HS1 regions of the FKS1 and FKS2 genes, are predictive of outcome.

What's new in the clinical and diagnostic management of invasive candidiasis in critically ill patients

Invasive candidiasis (IC) is a severe complication in the ICU setting. A high proportion of ICU patients become colonized with Candida species, but only 5-30 % develop IC. Progressive colonization and major abdominal surgery are well-known risk factors for Candida infection. IC is difficult to predict and early diagnosis remains a major challenge. In addition, microbiological documentation often occurs late in the course of infection. Delays in initiating appropriate treatment have been associated with increased mortality. In an attempt to decrease Candida-related mortality, an increasing number of critically ill patients without documented IC receive empirical systemic antifungal therapy, leading to concern for antifungal overuse. Scores/predictive rules permit the stratification and selection of IC high-risk patients who may benefit from early antifungal therapy. However, they have a far better negative predictive value than positive predictive value. New IC biomarkers [mannan, anti-mannan, (1,3)-β-D-glucan, and polymerase chain reaction] are being increasingly used to enable earlier diagnosis and, ideally, to provide prognostic information and/or therapeutic monitoring. Although reasonably sensitive and specific, these techniques remain largely investigational, and their clinical usefulness has yet to be established.