Excess Mortality, Hospital Stay, and Cost Due to Candidemia: A Case-Control Study Using Data From Population-Based Candidemia Surveillance

Procalcitonin as a marker of Candida species detection by blood culture and polymerase chain reaction in septic patients

Background

The aim of our study is to test procalcitonin (PCT) as surrogate marker of identification of Candida spp. by blood culture (BC) and real-time-polymerase chain reaction (PCR), whether alone or in association with bacteria, in septic patients.

Methods

We performed a single-centre retrospective study. We reviewed the clinical charts of patients with a diagnosis of severe sepsis or septic shock treated at our general intensive care unit from March 2009 to March 2013. We analysed all diagnostic episodes consisting of BC, real-time PCR assay and dosage of PCT. We registered age, sex, white blood count, sequential organ failure assessment score and type of admission between medical or surgical. When inclusion criteria were met more than once, we registered the new diagnostic episode as subsequent diagnostic episode. The diagnostic performance of PCT to predict Candida spp. identification alone or in mixed infections by either BC or PCR was tested using the receiver-operative characteristic curve. Logistic regression was constructed using presence of Candida spp. as the dependent variable.

Results

A total of 260 diagnostic episodes met the inclusion criteria. According to BC results classification, a significantly lower value of PCT was observed in Candida spp. BSI (0.99 ng/ml, 0.86 - 1.34) than in BSI caused by bacteria (16.7 ng/ml, 7.65 - 50.2) or in mixed infections (4.76 ng/ml, 2.98 - 6.08). Similar findings were observed considering PCR results. A cut-off of ≤ 6.08 ng/ml for PCT yielded a sensitivity of 86.8%, a specificity of 87.4%, a positive predictive value of 63.9%, a negative predictive value (NPV) of 96.3% and an area under the curve of 0.93 for Candida spp. identification by BC. A similar high NPV for a cut-off ≤ 6.78 ng/ml was observed considering the classification of diagnostic episodes according to PCR results, with an AUC of 0.85. A subsequent diagnostic episode was independently associated with Candida spp. detection either by BC or PCR.

Conclusion

PCT could represent a useful diagnostic tool to exclude the detection of Candida spp. by BC and PCR in septic patients.

Practical aspects of the management of patients with chronic hand eczema

Urgency. High prevalence ot hand eczema stipulates the urgency ot studies ot significant factors ot the torpid course ot this disease, which is a result ot the sensitizing power ot the pathogenic biota in most cases. Goal. Optimization ot the therapy ot true hand eczema associated with chronic paronychias. Materials and methods. The tollow-up study comprised 30 patients suttering trom true hand eczema associated with chronic paronychias who underwent clinical and laboratory examinations with the determination ot the severity ot eczema, skin contamination and level ot specitic anti-Candida antibodies. Results. The authors revealed an evident clinical and laboratory etticacy ot the monotherapy with the Triderm cream aimed at the elimination ot paronychias and hand eczema.

Histatin 5-spermidine conjugates have enhanced fungicidal activity and efficacy as a topical therapeutic for oral candidiasis

Oropharyngeal candidiasis (OPC) is caused by the opportunistic fungi Candida albicans and is prevalent in immunocompromised patients, individuals with dry mouth, or patients with prolonged antibiotic therapies that reduce oral commensal bacteria. Human salivary histatins, including histatin 5 (Hst 5), are small cationic proteins that are the major source of fungicidal activity of saliva. However, Hsts are rapidly degraded in vivo, limiting their usefulness as therapeutic agents despite their lack of toxicity. We constructed a conjugate peptide using spermidine (Spd) linked to the active fragment of Hst 5 (Hst 54-15), based upon our findings that C. albicans spermidine transporters are required for Hst 5 uptake and fungicidal activity. We found that Hst 54-15-Spd was significantly more effective in killing C. albicans and Candida glabrata than Hst 5 alone in both planktonic and biofilm growth and that Hst 54-15-Spd retained high activity in both serum and saliva. Hst 54-15-Spd was not bactericidal against streptococcal oral commensal bacteria and had no hemolytic activity. We tested the effectiveness of Hst 54-15-Spd in vivo by topical application to tongue surfaces of immunocompromised mice with OPC. Mice treated with Hst 54-15-Spd had significant clearance of candidal tongue lesions macroscopically, which was confirmed by a 3- to 5-log fold reduction of C. albicans colonies recovered from tongue tissues. Hst 54-15-Spd conjugates are a new class of peptide-based drugs with high selectivity for fungi and potential as topical therapeutic agents for oral candidiasis.

A novel renal epithelial cell in vitro assay to assess Candida albicans virulence

Candida albicans, an opportunistic fungal pathogen, can cause severe systemic infections in susceptible patient groups. Systemic candidiasis is mainly studied in the mouse intravenous challenge model, where progressive infection correlates with increased early renal chemokine levels. To develop a new in vitro assay to assess C. albicans virulence, which reflects the events occurring in the murine infection model, renal M-1 cortical collecting duct epithelial cells were evaluated as the early producers of cytokines in response to C. albicans. We show that renal epithelial cells respond only to live C. albicans cells capable of forming hyphae, producing chemokines KC and MIP-2, with levels correlating with epithelial cell damage. By assaying epithelial cell responses to strains of known virulence in the murine intravenous challenge model we demonstrate that renal epithelial cells can discriminate between virulent and attenuated strains. This simple, novel assay is a useful initial screen for altered virulence of C. albicans mutants or clinical isolates in vitro and provides an alternative to the mouse systemic infection model.

Effect of statin use on outcomes of adults with candidemia

Background

Statins have immunomodulatory properties and hinder Candida growth. However, it is unknown whether they may improve prognosis in patients with candidemia. We sought to determine the effect of prior statin use on the clinical outcomes of patients suffering candidemia.

Methods and Findings

Multicenter cohort study of hospitalized adults with candidemia between 2005 and 2011 in six hospitals in Spain, Brazil and Argentina. Of 326 candidemias, 44 (13.5%) occurred in statin users and 282 (86.5%) in statin non-users. The median value of APACHE II at candidemia diagnosis was similar between groups (18 vs. 16; p=.36). Candida albicans was the most commonly isolated species, followed by C. parapsilosis, C. tropicalis, C. glabrata, and C. krusei. There were no differences regarding appropriate empirical antifungal treatment. Statin users had a lower early (5 d) case-fatality rate than non-users (4.5 vs. 17%; p=.031). This effect was not observed with other cardiovascular drugs (aspirin, beta blockers and ACE inhibitors). Independent factor related to early case-fatality rate was APACHE II score (AOR, 1.08; 95% CI, 1.03–1.14; p=.002). An appropriate empirical antifungal therapy (AOR, 0.11; 95% CI, 0.04–0.26; p=<.001) and prior statin use were independently associated with lower early case-fatality (AOR, 0.17; 95% CI, 0.03–0.93; p=.041). Fourteen days (14d) and overall (30d) case-fatality rates were similar between groups (27% vs. 29%; p=0.77 and 40% vs. 44%; p=.66).

Conclusions

The use of statins might have a beneficial effect on outcomes of patients with candidemia. This hypothesis deserves further evaluation in randomized trials.

Nosocomial bloodstream infections due to Candida spp. in the USA: species distribution, clinical features and antifungal susceptibilities

Candida spp. are among the most frequent nosocomial pathogens, contributing significantly to morbidity and mortality. Longitudinal data on the epidemiology of Candida bloodstream infections (BSIs) are still limited. Isolates and clinical data from 1218 episodes of Candida BSI were prospectively collected from patients in 52 hospitals in the USA between 1998 and 2006. Susceptibilities to amphotericin B, flucytosine, fluconazole, posaconazole, voriconazole, anidulafungin, caspofungin and micafungin were determined for 1077 Candida isolates by the CLSI reference broth microdilution method using the recently published species-specific clinical breakpoints. Candida albicans was the most prevalent species (50.7%), followed by Candida parapsilosis (17.4%), Candida glabrata (16.7%) and Candida tropicalis (10.2%). The prevalence of non-albicans Candida spp. increased over time. Patients had a mean age of 51 years and a mean length of hospital stay prior to BSI of 22 days. The main underlying conditions were gastrointestinal (20.1%) and pulmonary (13.0%) diseases. Intravenous catheters (19.1%) and the urinary tract (8.0%) were the most frequently determined likely sources, whilst in the majority of patients (61.1%) no source could be identified. Overall mortality was 38.1%. Of the isolates studied, 0.8% of C. albicans, 100.0% of C. glabrata, 2.9% of C. parapsilosis and 4.9% of C. tropicalis were non-susceptible to fluconazole, and 0.6% of C. albicans, 5.0% of Candida krusei, 7.6% of C. parapsilosis and 9.8% of C. tropicalis were non-susceptible to voriconazole. All echinocandins showed good activity against most Candida spp., including the majority of C. parapsilosis isolates, but only 38.1% of C. glabrata tested susceptible to caspofungin.

Cranberry-derived proanthocyanidins prevent formation of Candida albicans biofilms in artificial urine through biofilm- and adherence-specific mechanisms

OBJECTIVES

Candida albicans is a common cause of nosocomial urinary tract infections (UTIs) and is responsible for increased morbidity and healthcare costs. Moreover, the US Centers for Medicare & Medicaid Services no longer reimburse for hospital-acquired catheter-associated UTIs. Thus, development of specific approaches for the prevention of Candida urinary infections is needed. Cranberry juice-derived proanthocyanidins (PACs) have efficacy in the prevention of bacterial UTIs, partially due to anti-adherence properties, but there are limited data on their use for the prevention and/or treatment of Candida UTIs. Therefore, we sought to systematically assess the in vitro effect of cranberry-derived PACs on C. albicans biofilm formation in artificial urine.

METHODS

C. albicans biofilms in artificial urine were coincubated with cranberry PACs at serially increasing concentrations and biofilm metabolic activity was assessed using the XTT assay in static microplate and silicone disc models.

RESULTS

Cranberry PAC concentrations of ≥16 mg/L significantly reduced biofilm formation in all C. albicans strains tested, with a paradoxical effect observed at high concentrations in two clinical isolates. Further, cranberry PACs were additive in combination with traditional antifungals. Cranberry PACs reduced C. albicans adherence to both polystyrene and silicone. Supplementation of the medium with iron reduced the efficacy of cranberry PACs against biofilms.

CONCLUSIONS

These findings indicate that cranberry PACs have excellent in vitro activity against C. albicans biofilm formation in artificial urine. We present preliminary evidence that cranberry PAC activity against C. albicans biofilm formation is due to anti-adherence properties and/or iron chelation.

Clinical practice guidelines for the management of invasive Candida infections in adults in the Middle East region: Expert panel recommendations

Invasive Candida infections contribute to significant morbidity and mortality in patients with healthcare-associated infections. They represent a major burden on the public health system, and are challenging to diagnose and treat. A multidisciplinary expert panel critically reviewed available evidence to provide consensus recommendations for the management of invasive Candida infections in the Middle East. Based on diagnosis, recommendations were provided for the management of Candida infections in non-neutropenic and neutropenic patients. Polyenes (amphotericin B-deoxycholate [AmB-d] and lipid formulations amphotericin B [LFAmB]), triazoles (fluconazole, itraconazole and voriconazole), echinocandins (caspofungin, anidulafungin, and micafungin) and flucytosine are the recommended categories of antifungal agents for treatment of Candida infections. Echinocandins are preferred for treatment of proven and suspected Candida infections, especially in critically ill patients or those with previous exposure to azoles. Recommendations were also provided for infections caused by specific Candida species as well as management of different disease conditions. The experts highlighted that the guidelines should be used along with clinical judgment. Given the paucity of published data from the region, research in the form of randomized clinical trials should be given priority.

Candida albicans VMA3 is necessary for V-ATPase assembly and function and contributes to secretion and filamentation

The vacuolar membrane ATPase (V-ATPase) is a protein complex that utilizes ATP hydrolysis to drive protons from the cytosol into the vacuolar lumen, acidifying the vacuole and modulating several key cellular response systems in Saccharomyces cerevisiae. To study the contribution of V-ATPase to the biology and virulence attributes of the opportunistic fungal pathogen Candida albicans, we created a conditional mutant in which VMA3 was placed under the control of a tetracycline-regulated promoter (tetR-VMA3 strain). Repression of VMA3 in the tetR-VMA3 strain prevents V-ATPase assembly at the vacuolar membrane and reduces concanamycin A-sensitive ATPase-specific activity and proton transport by more than 90%. Loss of C. albicans V-ATPase activity alkalinizes the vacuolar lumen and has pleiotropic effects, including pH-dependent growth, calcium sensitivity, and cold sensitivity. The tetR-VMA3 strain also displays abnormal vacuolar morphology, indicative of defective vacuolar membrane fission. The tetR-VMA3 strain has impaired aspartyl protease and lipase secretion, as well as attenuated virulence in an in vitro macrophage killing model. Repression of VMA3 suppresses filamentation, and V-ATPase-dependent filamentation defects are not rescued by overexpression of RIM8, MDS3, EFG1, CST20, or UME6, which encode positive regulators of filamentation. Specific chemical inhibition of Vma3p function also results in defective filamentation. These findings suggest either that V-ATPase functions downstream of these transcriptional regulators or that V-ATPase function during filamentation involves independent mechanisms and alternative signaling pathways. Taken together, these data indicate that V-ATPase activity is a fundamental requirement for several key virulence-associated traits in C. albicans.

Effect of jujube honey on Candida albicans growth and biofilm formation

BACKGROUND AND AIMS

Candida species, especially Candida albicans, are major fungal pathogens of humans that are capable of causing superficial mucosal infections and systemic infections in humans. The aim of this study was to evaluate the jujube (Zizyphus spina-christi) honey for its in vitro inhibitory activity against pre-formed biofilm and its interference with the biofilm formation of C. albicans.

METHODS

The XTT reduction assay, scanning electron microscopy (SEM) and atomic force microscopy (AFM) were employed to determine the inhibitory effect of Jujube honey on C. albicans biofilm. Changes in the infrared spectrum after treatment with honey were also determined by Fourier transform infrared (FTIR) spectroscopy.

RESULTS

Jujube honey affects biofilms by decreasing the size of mature biofilms and by disruption of their structure. At a concentration of 40% w/v, it interferes with formation of C. albicans biofilms and disrupts established biofilms. The SEM and AFM results indicated that this type of honey affected the cellular morphology of C. albicans and decreased biofilm thickness.

CONCLUSIONS

The present findings show that jujube honey has antifungal properties against C. albicans and has the ability to inhibit the formation of C. albicans biofilms and disrupt established biofilms.

Economic evaluation of voriconazole for the treatment of candidemia in Canadian adults

BACKGROUND

Candidemia is a common cause of nosocomial bloodstream infection. When selecting therapeutic treatments for candidemia, cost-effectiveness is an important consideration. The present study assessed the cost-effectiveness of voriconazole for the treatment of candidemia.

METHODS

A decision-analytical model was used for evaluating the cost-effectiveness of voriconazole compared with a regimen of conventional amphotericin B (CAB) followed by fluconazole (FLU) in the treatment of non-neutropenic patients diagnosed with candidemia in the Canadian setting, based on the Global Candidemia Study. The time frame of the model was 98 days (14 weeks). Model parameters were based primarily on clinical outcome, and resource use data collected from the clinical trial were used. Supplemental data were obtained from an independent panel of 12 Canadian experts for parameters not available from the clinical trial. Unit costs were collected from Canadian sources. The outcome variables selected in the study were the number of patients cured within 98 days, the number of patients surviving at 98 days and the number of patients avoiding toxicity. Incremental costs per outcome were calculated to compare the cost-effectiveness analyses (both probabilistic and one-way sensitivity analyses were performed).

RESULTS

The cost-effectiveness analysis demonstrated a difference of $1,121 in the total average cost of treatment with voriconazole ($70,489) versus CAB/FLU ($69,368). While the costs of voriconazole exceeded the costs of CAB/FLU, these costs were almost completely offset by lower hospitalization costs. While patients in both treatment arms experienced cure rates of 41%, both the percentage of patients surviving at day 98 (64.5% versus 58.2%) and the percentage of patients avoiding toxicity (64.5% versus 52.5%) were higher in the voriconazole arm. Accounting for differences in total costs and clinical outcomes, this analysis estimated an incremental cost per patient surviving at day 98 of $17,739, and an incremental cost per patient avoiding toxicity of $9,298. In the case of cost per patient cured, voriconazole had a higher cost ($1,121) than CAB/FLU. The results of the deterministic and probabilistic sensitivity analyses indicated that the model was robust.

CONCLUSIONS

Results of the decision-analytical model provided evidence to support the cost-effectiveness of voriconazole relative to a regimen of CAB/FLU in the treatment of non-neutropenic patients diagnosed with candidemia in the Canadian setting.

Candida krusei colonization in patients with gastrointestinal diseases

A total of 135 stomach samples from patients with gastrointestinal diseases and normal controls were examined for Helicobacter pylori infection and Candida colonization. Candida krusei was found in specimens from 20% bleeding, 52% ulcer, and 100% gastritis patients, whereas H. pylori infection rates were 82%, 35% and 30%, respectively, for the same groups of patients. C. krusei was not detected in stomach samples from normal controls.

The role of Candida albicans AP-1 protein against host derived ROS in in vivo models of infection

Candida albicans is a major fungal pathogen of humans, causing mucosal infections that are difficult to eliminate and systemic infections that are often lethal primarily due to defects in the host's innate status. Here we demonstrate the utility of Caenorhabditis elegans, a model host to study innate immunity, by exploring the role of reactive oxygen species (ROS) as a critical innate response against C. albicans infections. Much like a human host, the nematode's innate immune response is activated to produce ROS in response to fungal infection. We use the C. albicans cap1 mutant, which is susceptible to ROS, as a tool to dissect this physiological innate immune response and show that cap1 mutants fail to cause disease and death, except in bli-3 mutant worms that are unable to produce ROS because of a defective NADPH oxidase. We further validate the ROS-mediated host defense mechanism in mammalian phagocytes by demonstrating that chemical inhibition of the NADPH oxidase in cultured macrophages enables the otherwise susceptible cap1 mutant to resists ROS-mediated phagolysis. Loss of CAP1 confers minimal attenuation of virulence in a disseminated mouse model, suggesting that CAP1-independent mechanisms contribute to pathogen survival in vivo. Our findings underscore a central theme in the process of infection-the intricate balance between the virulence strategies employed by C. albicans and the host's innate immune system and validates C. elegans as a simple model host to dissect this balance at the molecular level.

Efficacy of micafungin in invasive candidiasis caused by common Candida species with special emphasis on non-albicans Candida species

The incidence of invasive candidiasis caused by non-albicans Candida (NAC) spp. is increasing. The aim of this analysis was to evaluate the efficacy of micafungin, caspofungin and liposomal amphotericin B in patients with invasive candidiasis and candidaemia caused by different Candida spp. This post hoc analysis used data obtained from two randomised phase III trials was conducted to evaluate the efficacy and safety of micafungin vs. caspofungin and micafungin vs. liposomal amphotericin B. Treatment success, clinical response, mycological response and mortality were evaluated in patients infected with C. albicans and NAC spp. Treatment success rates in patients with either C. albicans or NAC infections were similar. Outcomes were similar for micafungin, caspofungin and liposomal amphotericin B. Candida albicans was the most prevalent pathogen recovered (41.0%), followed by C. tropicalis (17.9%), C. parapsilosis (14.4%), C. glabrata (10.4%), multiple Candida spp. (7.3%) and C. krusei (3.2%). Age, primary diagnosis (i.e. candidaemia or invasive candidiasis), previous corticosteroid therapy and Acute Physiology and Chronic Health Evaluation II score were identified as potential predictors of treatment success and mortality. Micafungin, caspofungin and liposomal amphotericin B exhibit favourable treatment response rates that are comparable for patients infected with different Candida spp.

[Towards an early diagnosis of invasive candidiasis in the critically ill patient]

The management of invasive fungal infections in critically ill patients, from diagnosis to selection of the therapeutic protocol, is often a challenge. Early diagnosis and treatment are associated with a better prognosis, but apart from cases with positive cultures from blood or fluid/tissue biopsy, diagnosis is neither sensitive nor specific, and there is a need for specific markers in these diseases. Serodiagnostic assays such as mannan antigen, mannan antibodies, Candida albicans germ-tube antibodies or (1→3)-β-D-glucan detection, and molecular techniques for the detection of fungal-specific DNA have been developed with promising results in critical care settings. One of the main features in diagnosis is the evaluation of risk factors for infection, which will identify patients in need of preemptive or empirical treatment. Clinical scores were built from those risk factors. The combination of prediction rules and non-culture microbiological tools could be currently be the key to improving the diagnosis and prognosis of invasive fungal infections in critically ill patients.

Brazilian guidelines for the management of candidiasis - a joint meeting report of three medical societies: Sociedade Brasileira de Infectologia, Sociedade Paulista de Infectologia and Sociedade Brasileira de Medicina Tropical

Candida infections account for 80% of all fungal infections in the hospital environment, including bloodstream, urinary tract and surgical site infections. Bloodstream infections are now a major challenge for tertiary hospitals worldwide due to their high prevalence and mortality rates. The incidence of candidemia in tertiary public hospitals in Brazil is approximately 2.5 cases per 1000 hospital admissions. Due to the importance of this infection, the authors provide a review of the diversity of the genus Candida and its clinical relevance, the therapeutic options and discuss the treatment of major infections caused by Candida. Each topography is discussed with regard to epidemiological, clinical and laboratory diagnostic and therapeutic recommendations based on levels of evidence.

Management of candidaemia and invasive candidiasis in critically ill patients

Critically ill patients in the intensive care unit (ICU) are at increased risk of encountering bloodstream infections (BSIs) with Candida spp., associated with an elevated crude mortality rate. This supports the significance of early detection of infection and identification of the most effective management approach. A review of the various antifungal treatments and an evaluation of the diverse management approaches for invasive candidiasis in critically ill patients is necessary for guiding evidence-based decision-making. Different early detection schemes for invasive candidiasis are well documented in the literature. Other than the common use of blood cultures, new methods entail the use of risk prediction scores and biomarker tests. Regarding management strategies, different options are currently supported. These include prophylaxis, empirical therapy, pre-emptive therapy, and treatment of culture-documented infections. The choice of treatment is greatly dependent on several factors related to the patient and/or to the surrounding environment. Attention needs to be given to previous exposure to azoles, epidemiological data on dominant Candida spp. in local ICUs, severity of illness and associated morbidities. This paper summarises the most recent literature as well as the guidelines issued by the Infectious Diseases Society of America. The objective is to identify the best diagnosis and management approaches for serious Candida infections in critically ill patients. In addition, this article addresses an important aspect associated with managing candidaemia in critically ill patients pertaining to the decision for intravenous catheter removal.

Occurrence, presentation and treatment of candidemia

Candida is one of the most common causes of nosocomial bloodstream infections. Candidemia is not confined to hematological patients, intensive care units or abdominal surgery wards, but it is remarkably frequent in the internal medicine setting. High mortality associated with candidemia can be reduced by prompt, appropriate antifungal therapy. The epidemiology of species has been shifting toward non-albicans strains. Significant improvements in nonculture-based diagnostic methods, such as serological markers, have been made in recent years, and novel diagnostic techniques should be further studied to enable early pre-emptive therapy. Treatment guidelines indicate that echinocandins are at present the best choice for patients who are severely ill or possibly infected with fluconazole-resistant strains.

Invasive fungal infections in acute leukemia

Invasive fungal infection (IFI) is among the leading causes for morbidity, mortality, and economic burden for patients with acute leukemia. In the past few decades, the incidence of IFI has increased dramatically. The certainty of diagnosis of IFI is based on host factors, clinical evidence, and microbiological examination. Advancement in molecular diagnostic modalities (e.g. non-culture-based serum biomarkers such as β-glucan or galactomannan assays) and high-resolution radiological imaging has improved our diagnostic approach. The early use of these diagnostic tests assists in the early initiation of preemptive therapy. Nonetheless, the complexity of IFI in patients with leukemia and the limitations of these diagnostic tools still mandate astute clinical acumen. Its management has been further complicated by the increasing frequency of infection by non-Aspergillus molds (e.g. zygomycosis) and the emergence of drug-resistant fungal pathogens. In addition, even though the antifungal armamentarium has expanded rapidly in the past few decades, the associated mortality remains high. The decision to initiate antifungal treatment and the choice of anti-fungal therapy requires careful consideration of several factors (e.g. risk stratification, local fungal epidemiologic patterns, concomitant comorbidities, drug-drug interactions, prior history of antifungal use, overall cost, and the pharmacologic profile of the antifungal agents). In order to optimize our diagnostic and therapeutic management of IFI in patients with acute leukemia, further basic research and clinical trials are desperately needed.

Fungal diagnosis: how do we do it and can we do better?

BACKGROUND

Morbidity and mortality remain high for patients with invasive fungal infections (IFIs) despite an increasing number of antifungals and other treatments. Many studies indicate that delayed or inaccurate diagnosis and treatment are major causes of poor outcomes in patients with IFIs.

OBJECTIVE

The aim of the current paper is to provide a review of traditional and newer approaches to the diagnosis of IFIs, with a particular focus on invasive candidiasis (IC) and aspergillosis (IA). Recent studies from the author's institution are highlighted, along with an advancement in cryptococcal meningitis diagnosis that should improve the care of AIDS and its opportunistic infection in many developing countries.

FINDINGS

Currently available tools for the diagnosis of IFIs include traditional methods like histopathology, culture, and radiology, and newer antigen- and PCR-based diagnostic assays. Attempts have also been made to predict IFIs based on colonization or other factors, including genetic polymorphisms impacting IFI susceptibility in high-risk patients. Biopsy with histopathologic analysis is often not possible in patients suspected of pulmonary aspergillosis due to increased bleeding risk, and blood cultures for IC, IA, or other IFIs are hindered by poor sensitivity and slow turnaround time which delays diagnosis. Radiology is often used to predict IFI but suffers from inability to differentiate certain pathogens and does not generally provide certainty of IFI diagnosis. Newer antigen-based diagnostics for early diagnosis include the β-glucan assay for IFIs, galactomannan assay for IA, and a recent variation on the traditional cryptococcal antigen (CRAG) test with a Lateral Flow Assay for invasive cryptococcosis. PCR-based diagnostics represent additional tools with high sensitivity for the rapid diagnosis of IFIs, although better standardization of these methods is still required for their routine clinical use.

CONCLUSION

Better understanding of the strengths and weaknesses of currently available diagnostic tools, and further devising linked strategies to best implement them either alone or in combination, would greatly improve early and accurate diagnosis of IFIs and improve their successful management.

Multilocus sequence typing of Candida tropicalis shows the presence of different clonal clusters and fluconazole susceptibility profiles in sequential isolates from candidemia patients in Sao Paulo, Brazil

The profiles of 61 Candida tropicalis isolates from 43 patients (28 adults and 15 children) diagnosed with candidemia at two teaching hospitals in São Paulo, Brazil, were characterized by multilocus sequence typing (MLST). For the 14 patients who had bloodstream infections, 32 isolates were serially collected from their blood and/or catheters. Thirty-nine diploid sequence types (DSTs) were differentiated. According to the C. tropicalis MLST database (http://pubmlst.org/ctropicalis/), 36 DSTs and 23 genotypes identified from the 61 isolates had not previously been described. This report represents the first study to characterize sequential isolates of C. tropicalis from candidemia cases in South America. Microvariation in a single gene was found in the sequential isolates from 7 patients. The main polymorphisms occurred in the alleles of the XYR1 gene, specifically at nucleotide positions 215, 242, and 344. Macrovariation in six gene fragments was detected in the isolates from 3 patients. eBURST analysis added two new groups to this study (groups 6 and 18). Additionally, susceptibility tests indicate that 3 isolates were resistant to fluconazole. No correlation was found between the DSTs and susceptibility to fluconazole and/or selective antifungal pressure. Two patients were sequentially infected with resistant and susceptible strains. MLST is an important tool for studying the genetic diversity of multiple/sequential isolates of patients with candidemia, allowing the comparison of our data with those from other regions of the world, as well as allowing an analysis of the genetic relationship among several clones in sequential isolates from the same or different candidemia patient sites (blood or catheter).

The epidemiology of neonatal and pediatric candidemia in England and Wales, 2000-2009

BACKGROUND

There are few population-based studies on the epidemiology of neonatal and pediatric invasive Candida infections, despite their significant clinical impact on patients. This study aimed to describe the epidemiology of pediatric candidemia in England and Wales during a 10-year period as a means of quantifying the changing burden of infection and identifying emerging trends.

METHODS

National Health Service hospital microbiology laboratories in England and Wales routinely report clinically significant invasive infections electronically to the Health Protection Agency. Records of all positive blood cultures for Candida species in children aged <15 years between 2000 and 2009 inclusive were extracted for analysis.

RESULTS

During 2000 to 2009, 1473 childhood candidemia cases were reported in England and Wales (annual incidence, 1.52/100,000 person-years), with the highest rate in <1 year olds (n = 706; 11.0/100,000), followed by 1-4 year olds (n = 440; 1.77/100,000), 5-9 year olds (n = 168; 0.53/100,000) and 10-14 year olds (n = 159; 0.47/100,000). Incidence increased from 1.04 per 100,000 in 2000 to 2.09 per 100,000 in 2007 (P < 0.001) before falling to 1.53 per 100,000 in 2009 (P < 0.001). Candida species was reported in 89.6% (1320/1473) cases, with Candida albicans and Candida parapsilosis accounting for most infections in all age groups. There were no significant differences in species distribution by season or year of study and the proportion of non-albicans cases did not increase with time.

CONCLUSIONS

Pediatric candidemia rates are beginning to fall in England and Wales. C. albicans continues to account for most Candida bloodstream infections in all age groups with no evidence of increases in non-albicans species.

Nationwide study of candidemia, antifungal use, and antifungal drug resistance in Iceland, 2000 to 2011

Candidemia is often a life-threatening infection, with highly variable incidence among countries. We conducted a nationwide study of candidemia in Iceland from 2000 to 2011, in order to determine recent trends in incidence rates, fungal species distribution, antifungal susceptibility patterns, and concurrent antifungal consumption. A total of 208 infection episodes in 199 patients were identified. The average incidence during the 12 years was 5.7 cases/100,000 population/year, which was significantly higher than that from 1990 to 1999 (4.3/100,000/year; P = 0.02). A significant reduction in the use of blood cultures was noted in the last 3 years of the study, coinciding with the economic crisis in the country (P < 0.001). Age-specific incidence rates were highest among patients at the extremes of age, 20.7/100,000 for <1 year of age and 18.1/100,000 for >60 years, and varied by gender. Age-specific incidence among males >80 years old was 28.6/100,000/year, and it was 8.3/100,000/year for females in this age group (P = 0.028). The 30-day survival rate among adult patients remained unchanged compared to that from 1990 to 1999 (70.4% versus 69.5%, P = 0.97). Candida albicans was the predominant species (56%), followed by C. glabrata (16%) and C. tropicalis (13%). The species distribution remained stable compared to that from previous decades. Fluconazole use increased 2.4-fold from 2000 to 2011, with no increase in resistance. In summary, the incidence of candidemia in Iceland has continued to increase but may have reached a steady state, and no increase in antifungal drug resistance has been noted. Decreased use of blood cultures toward the end of the study may have influenced detection rates.

Microbiological profile of organisms causing bloodstream infection in critically ill patients

Background

Bloodstream infection (BSI) is the most frequent infection in critically ill patients. As BSI’s among patients in intensive care units (ICU’s) are usually secondary to intravascular catheters, they can be caused by both Gram-positive and Gram-negative microorganisms as well as fungi. Infection with multidrug-resistant (MDR) organisms is becoming more common, making the choice of empirical antimicrobial therapy challenging. The objective of this study is to evaluate the spectrum of microorganisms causing BSI’s in a Medical-Surgical Intensive Care Unit (MSICU) and their antimicrobial resistance patterns.

Methods

A prospective observational study among all adult patients with clinical signs of sepsis was conducted in a MSICU of an inner-city hospital in New York City between May 1, 2010 and May 30, 2011.

Results

A total of 722 adult patients with clinical signs of systemic inflammatory response syndrome (SIRS) and/or sepsis were admitted to the MSICU between May 1, 2010 and May 30, 2011. From those patients, 91 (12.6%) had one or more positive blood culture. A 122 isolates were identified: 72 (59%) were Gram-positive bacteria, 38 (31.1%) were Gram-negative organisms, and 12 (9.8%) were fungi. Thirteen (34.2%) Gram-negative organisms and 14 (19.4%) Gram-positive bacteria were classified as MDR.

Conclusions

Antimicrobial resistance, particularly among Gram-negative organisms, continues to increase at a rapid rate, especially in the ICU’s. Coordinated infection control interventions and antimicrobial stewardship policies are warranted in order to slow the emergence of resistance.

The PATH (Prospective Antifungal Therapy) Alliance® registry and invasive fungal infections: update 2012

The Prospective Antifungal Therapy Alliance (PATH Alliance®) performed prospective surveillance of invasive fungal infections (IFIs) among patients hospitalized at 25 medical centers in North America between 2004 and 2008, collecting information on the epidemiology, diagnosis, treatment, and mortality rates of IFIs. In total, 7526 IFIs were identified in 6845 patients. Candida spp. (73.4%) were the most common pathogens, followed by Aspergillus spp. (13.3%), and other yeasts (6.2%). Culture was the most frequently used diagnostic test in the majority of IFI categories. Most patients with invasive candidiasis were treated with fluconazole (48.3%) and the echinocandins (34.0%), while voriconazole (45.5%) was the main antifungal agent for invasive aspergillosis. The 12-week survival rate ranged from 37.5% for hematopoietic stem cell transplant recipients to ~75.0% for those with HIV/AIDS. In summary, the findings of the PATH Alliance® registry provide a better understanding of the epidemiology of a vast variety and large numbers of IFIs.

Species identification and antifungal susceptibility testing of Candida bloodstream isolates from population-based surveillance studies in two U.S. cities from 2008 to 2011

Between 2008 and 2011, population-based candidemia surveillance was conducted in Atlanta, GA, and Baltimore, MD. Surveillance had been previously performed in Atlanta in 1992 to 1993 and in Baltimore in 1998 to 2000, making this the first population-based candidemia surveillance conducted over multiple time points in the United States. From 2,675 identified cases of candidemia in the current surveillance, 2,329 Candida isolates were collected. Candida albicans no longer comprised the majority of isolates but remained the most frequently isolated species (38%), followed by Candida glabrata (29%), Candida parapsilosis (17%), and Candida tropicalis (10%). The species distribution has changed over time; in both Atlanta and Baltimore the proportion of C. albicans isolates decreased, and the proportion of C. glabrata isolates increased, while the proportion of C. parapsilosis isolates increased in Baltimore only. There were 98 multispecies episodes, with C. albicans and C. glabrata the most frequently encountered combination. The new species-specific CLSI Candida MIC breakpoints were applied to these data. With the exception of C. glabrata (11.9% resistant), resistance to fluconazole was very low (2.3% of isolates for C. albicans, 6.2% for C. tropicalis, and 4.1% for C. parapsilosis). There was no change in the proportion of fluconazole resistance between surveillance periods. Overall echinocandin resistance was low (1% of isolates) but was higher for C. glabrata isolates, ranging from 2.1% isolates resistant to caspofungin in Baltimore to 3.1% isolates resistant to anidulafungin in Atlanta. Given the increase at both sites and the higher echinocandin resistance, C. glabrata should be closely monitored in future surveillance.

Evaluation of four pretreatment procedures for MALDI-TOF MS yeast identification in the routine clinical laboratory

MALDI-TOF MS-based yeast identification requires a pretreatment step for which four are described in the literature, i.e., direct smear, fast formic acid and two complete formic acid/acetonitrile extractions. In this study we compared the impact of these procedures on the performance of MALDI-TOF MS-based yeast identification of samples from colonies grown on Sabouraud or chromogenic media. A total of 103 yeast isolates recovered from clinical samples were identified in parallel using the four pretreatment procedures. The proportions of both correct identifications (regardless of LogScore values) and of reliable identifications (i.e., correct identifications with a LogScore 2, as recommended by the manufacturer) obtained with the four techniques were compared. Even if the proportion of correct identifications exceeded 85% independent of the pretreatment procedure, results obtained with complete formic acid/acetonitril extractions of colonies grown on Sabouraud media were significantly superior to those with smear and fast formic acid extraction procedures. If one considers only reliable identifications, then both smear and fast formic acid extraction procedures yielded lower (<40%) correct identification rates than the use of the two complete extraction procedures (>77%) of portions of colonies on both Sabouraud and chromogenic media. The data would indicate that the direct smear and fast formic acid procedures cannot be recommended due to the LogScore values which were continually below those recommended by the manufacturer for biological validation. Thus, complete extraction methods are better suited for MALDI-TOF MS-based yeast identification in the clinical laboratory setting although they are more labor-intensive.

Accurate and rapid identification of Candida spp. frequently associated with fungemia by using PCR and the microarray-based Prove-it Sepsis assay

The rapid identification of microbes responsible for bloodstream infections (BSIs) allows more focused and effective therapies and outcomes. DNA sequence-based methods offer an opportunity for faster, accurate diagnosis and for effective therapy. As our objective of the study, the ability of the Prove-it Sepsis platform, already proven as a rapid PCR- and microarray-based assay for the majority of sepsis-causing bacteria, was extended to also rapidly identify clinically relevant yeasts in blood culture. The performance characteristics of this extended platform are described. We found that the extended diagnostic Prove-it Sepsis platform was found to be highly accurate when analyzing primary isolates, spiked blood cultures, nucleic acid extracts from a retrospective blood culture data set, and primary blood cultures. Comparison of the blood culture results from the Prove-it Sepsis platform with those from conventional culture-based methods or by gene sequencing demonstrated a sensitivity of 99% and a specificity of 98% for fungal targets (based on analysis of a total of 388 specimens). Total assay time was 3 h from DNA extraction to BSI diagnosis. These results extend the performance characteristics of the Prove-it platform for bacteria to the easy, rapid, and accurate detection and species identification of yeasts in positive blood cultures. Incorporation of this extended and rapid diagnostic platform into the tools for clinical patient management would allow possibly faster identification and more focused therapies for BSIs.

Is the incidence of candidemia caused by Candida glabrata increasing in Brazil? Five-year surveillance of Candida bloodstream infection in a university reference hospital in southeast Brazil

From 2006 to 2010, a retrospective study was conducted in a university referral tertiary care hospital to study the frequency and distribution of Candida species in different medical specialties. The use of mechanical ventilation, central venous catheter, and urinary catheter were recorded per 1,000 patient-days and the use of antifungals was calculated using defined daily dose (DDD). A total of 313 episodes were identified and the overall incidence was 0.54 (0.41-0.71) episodes per 1,000 patient-days. Candida albicans caused 44% of the overall episodes, followed by C. tropicalis (21.7%), C. parapsilosis (14.4%), C. glabrata (11.2%), and C. krusei (3.5%). The incidence of C. glabrata significantly increased from 2006-2010 (range: 4.8-23.5%) (P = 0.024). Candida glabrata was associated with malignancies (P = 0.004) and C. krusei with hematologic malignancies (P < 0.0001). The use of antifungals was higher in the hematology/bone marrow transplant units and represented 40% of all fluconazole prescription in the hospital. There was no correlation with the use of fluconazole and the increasing ratio of C. glabrata (r = 0.60). The use of invasive devices was significantly higher in the intensive care units (ICUs) than the medical and surgical emergencies units (P < 0.001). In contrast, the emergencies had higher incidence of candidemia (2-2.1 episodes/1,000 patient-days) than the ICUs (1.6 episodes 1,000 patient-days). Candida glabrata candidemia showed a significant increase in contrast to the current national literature where C. parapsilosis remained the most important non-C. albicans Candida species in Brazilian hospitals. Our findings suggested that the increasing incidence of C. glabrata was not associated with use of fluconazole and other risk factors might play an important role.

Canadian clinical practice guidelines for invasive candidiasis in adults

Candidemia and invasive candidiasis (C/IC) are life-threatening opportunistic infections that add excess morbidity, mortality and cost to the management of patients with a range of potentially curable underlying conditions. The Association of Medical Microbiology and Infectious Disease Canada developed evidence-based guidelines for the approach to the diagnosis and management of these infections in the ever-increasing population of at-risk adult patients in the health care system. Over the past few years, a new and broader understanding of the epidemiology and pathogenesis of C/IC has emerged and has been coupled with the availability of new antifungal agents and defined strategies for targeting groups at risk including, but not limited to, acute leukemia patients, hematopoietic stem cell transplants and solid organ transplants, and critical care unit patients. Accordingly, these guidelines have focused on patients at risk for C/IC, and on approaches of prevention, early therapy for suspected but unproven infection, and targeted therapy for probable and proven infection.

Changes in incidence and antifungal drug resistance in candidemia: results from population-based laboratory surveillance in Atlanta and Baltimore, 2008-2011

BACKGROUND

Candidemia is common and associated with high morbidity and mortality; changes in population-based incidence rates have not been reported.

METHODS

We conducted active, population-based surveillance in metropolitan Atlanta, Georgia, and Baltimore City/County, Maryland (combined population 5.2 million), during 2008-2011. We calculated candidemia incidence and antifungal drug resistance compared with prior surveillance (Atlanta, 1992-1993; Baltimore, 1998-2000).

RESULTS

We identified 2675 cases of candidemia with 2329 isolates during 3 years of surveillance. Mean annual crude incidence per 100 000 person-years was 13.3 in Atlanta and 26.2 in Baltimore. Rates were highest among adults aged ≥65 years (Atlanta, 59.1; Baltimore, 72.4) and infants (aged <1 year; Atlanta, 34.3; Baltimore, 46.2). In both locations compared with prior surveillance, adjusted incidence significantly declined for infants of both black and white race (Atlanta: black risk ratio [RR], 0.26 [95% confidence interval {CI}, .17-.38]; white RR: 0.19 [95% CI, .12-.29]; Baltimore: black RR, 0.38 [95% CI, .22-.64]; white RR: 0.51 [95% CI: .29-.90]). Prevalence of fluconazole resistance (7%) was unchanged compared with prior surveillance; 32 (1%) isolates were echinocandin-resistant, and 9 (8 Candida glabrata) were multidrug resistant to both fluconazole and an echinocandin.

CONCLUSIONS

We describe marked shifts in candidemia epidemiology over the past 2 decades. Adults aged ≥65 years replaced infants as the highest incidence group; adjusted incidence has declined significantly in infants. Use of antifungal prophylaxis, improvements in infection control, or changes in catheter insertion practices may be contributing to these declines. Further surveillance for antifungal resistance and efforts to determine effective prevention strategies are needed.

Assessment of candidemia-attributable mortality in critically ill patients using propensity score matching analysis

Introduction

Candidemia in critically ill patients is usually a severe and life-threatening condition with a high crude mortality. Very few studies have focused on the impact of candidemia on ICU patient outcome and attributable mortality still remains controversial. This study was carried out to determine the attributable mortality of ICU-acquired candidemia in critically ill patients using propensity score matching analysis.

Methods

A prospective observational study was conducted of all consecutive non-neutropenic adult patients admitted for at least seven days to 36 ICUs in Spain, France, and Argentina between April 2006 and June 2007. The probability of developing candidemia was estimated using a multivariate logistic regression model. Each patient with ICU-acquired candidemia was matched with two control patients with the nearest available Mahalanobis metric matching within the calipers defined by the propensity score. Standardized differences tests (SDT) for each variable before and after matching were calculated. Attributable mortality was determined by a modified Poisson regression model adjusted by those variables that still presented certain misalignments defined as a SDT > 10%.

Results

Thirty-eight candidemias were diagnosed in 1,107 patients (34.3 episodes/1,000 ICU patients). Patients with and without candidemia had an ICU crude mortality of 52.6% versus 20.6% (P < 0.001) and a crude hospital mortality of 55.3% versus 29.6% (P = 0.01), respectively. In the propensity matched analysis, the corresponding figures were 51.4% versus 37.1% (P = 0.222) and 54.3% versus 50% (P = 0.680). After controlling residual confusion by the Poisson regression model, the relative risk (RR) of ICU- and hospital-attributable mortality from candidemia was RR 1.298 (95% confidence interval (CI) 0.88 to 1.98) and RR 1.096 (95% CI 0.68 to 1.69), respectively.

Conclusions

ICU-acquired candidemia in critically ill patients is not associated with an increase in either ICU or hospital mortality.

Rapid redistribution of phosphatidylinositol-(4,5)-bisphosphate and septins during the Candida albicans response to caspofungin

We previously showed that phosphatidylinositol-(4,5)-bisphosphate [PI(4,5)P2] and septin regulation play major roles in maintaining Candida albicans cell wall integrity in response to caspofungin and other stressors. Here, we establish a link between PI(4,5)P2 signaling and septin localization and demonstrate that rapid redistribution of PI(4,5)P2 and septins is part of the natural response of C. albicans to caspofungin. First, we studied caspofungin-hypersusceptible C. albicans irs4 and inp51 mutants, which have elevated PI(4,5)P2 levels due to loss of PI(4,5)P2-specific 5'-phosphatase activity. PI(4,5)P2 accumulated in discrete patches, rather than uniformly, along surfaces of mutants in yeast and filamentous morphologies, as visualized with a green fluorescent protein (GFP)-pleckstrin homology domain. The patches also contained chitin (calcofluor white staining) and cell wall protein Rbt5 (Rbt5-GFP). By transmission electron microscopy, patches corresponded to plasma membrane invaginations that incorporated cell wall material. Fluorescently tagged septins Cdc10 and Sep7 colocalized to these sites, consistent with well-described PI(4,5)P2-septin physical interactions. Based on expression patterns of cell wall damage response genes, irs4 and inp51 mutants were firmly positioned within a group of caspofungin-hypersusceptible, septin-regulatory protein kinase mutants. irs4 and inp51 were linked most closely to the gin4 mutant by expression profiling, PI(4,5)P2-septin-chitin redistribution and other phenotypes. Finally, sublethal 5-min exposure of wild-type C. albicans to caspofungin resulted in redistribution of PI(4,5)P2 and septins in a manner similar to those of irs4, inp51, and gin4 mutants. Taken together, our data suggest that the C. albicans Irs4-Inp51 5'-phosphatase complex and Gin4 function upstream of PI(4,5)P2 and septins in a pathway that helps govern responses to caspofungin.

Effects of carbapenems and their combination with amikacin on murine gut colonisation by Candida albicans

Carbapenems are broad-spectrum antibiotics increasingly used for the treatment of severe infections. We evaluated the effects of four carbapenems given as monotherapies or in combination with amikacin on the level of gastrointestinal colonisation by Candida albicans in a previously established mouse model. Adult male Crl : CD1 (ICR) BR mice were fed chow containing C. albicans or regular chow. The mice fed with Candida chow had their gut colonised by the yeast. Both groups were subsequently given imipenem, meropenem, ertapenem, doripenem or their combination with amikacin or normal saline subcutaneously for 10 days. Stool cultures were performed immediately before, at the end and 1 week after discontinuation of treatment. Candida-colonised mice treated with the antibiotics had higher counts of the yeast in their stools than control C. albicans-colonised animals treated with saline. All four carbapenems and their combination with amikacin caused a significant increase in C. albicans concentration. Mice fed regular chow and treated with the study antibiotics or saline did not have any Candida in their stools. Dissemination of Candida was not detected in any animal. These data suggest that carbapenems and carbapenem plus amikacin induce substantial increases in the murine intestinal concentration of C. albicans.

Importance of pharmacokinetic considerations for selecting therapy in the treatment of invasive fungal infections

Invasive fungal infections continue to be a significant cause of morbidity and mortality among at-risk patients. Over the last decade, the epidemiology of invasive mycoses has been defined by increasing rates of infection caused by azole-resistant yeast (Candida glabrata, Candida krusei), Aspergillus, and in some centers, non-Aspergillus moulds, such as Fusarium species, Scedosporium species, and Mucorales. Early and appropriate antifungal therapy is crucial for a favorable clinical outcome. When selecting antifungal therapy--especially during the initial acute phases of treatment--spectrum of activity and pharmacokinetic characteristics are key treatment considerations. Important pharmacokinetic considerations for selecting antifungal therapy in the treatment of invasive fungal infections include drug-drug interactions and variability in adsorption that may limit efficacy during the early phase of treatment, poor oral availability, and variable tissue distribution. A patient's underlying condition and pharmacogenetics also may affect the pharmacokinetics of antifungal drugs, resulting in interpatient pharmacokinetic differences.

Length of stay and charges associated with health care-acquired bloodstream infections

BACKGROUND

Although many studies have examined outcomes of health care-associated bloodstream infections (HCABSIs), population-based estimates of length of stay (LOS) and costs have seldom been reported.

OBJECTIVES

Our objective was to generate US national estimates of LOS and costs associated with HCABSIs using the 2003 National Inpatient Sample (NIS).

METHODS

This study utilized a matched case-control design to estimate LOS and costs associated with HCABSIs based on the 2003 (NIS). A special set of ICD-9-CM codes was used to identify cases. A 1:1 matching procedure was used in which HCABSIs in patients were matched with uninfected patients based on age, sex, and admission diagnosis. We performed weighted analysis to construct population estimates and their standard deviations for LOS and total charges.

RESULTS

After applying the case finding criteria, 113,436 HCABSI cases were identified. The weighted mean LOS for HCABSIs cases was 16.0 days compared with 5.4 days for the control group (P < .001). The weighted mean total charges for patients with HCABSIs were $85,813 ($110,183 US in 2010) compared with $22,821 ($29,302 US in 2010) for uninfected patients (P < .001). We estimated that, in 2003, HCABSIs potentially cost the US economy nearly $29 billion ($37.24 billion US in 2010).

CONCLUSION

This study estimated the economic burden of HCABSIs on the US national economy. With some modifications, the annually published NIS data could be useful as a national surveillance tool for health care adverse events including HCABSIs.

Risk factors and outcomes of candidemia caused by biofilm-forming isolates in a tertiary care hospital

Background

Very few data exist on risk factors for developing biofilm-forming Candida bloodstream infection (CBSI) or on variables associated with the outcome of patients treated for this infection.

Methods and Findings

We identified 207 patients with CBSI, from whom 84 biofilm-forming and 123 non biofilm-forming Candida isolates were recovered. A case-case-control study to identify risk factors and a cohort study to analyze outcomes were conducted. In addition, two sub-groups of case patients were analyzed after matching for age, sex, APACHE III score, and receipt of adequate antifungal therapy. Independent predictors of biofilm-forming CBSI were presence of central venous catheter (odds ratio [OR], 6.44; 95% confidence interval [95% CI], 3.21–12.92) or urinary catheter (OR, 2.40; 95% CI, 1.18–4.91), use of total parenteral nutrition (OR, 5.21; 95% CI, 2.59–10.48), and diabetes mellitus (OR, 4.47; 95% CI, 2.03–9.83). Hospital mortality, post-CBSI hospital length of stay (LOS) (calculated only among survivors), and costs of antifungal therapy were significantly greater among patients infected by biofilm-forming isolates than those infected by non-biofilm-forming isolates. Among biofilm-forming CBSI patients receiving adequate antifungal therapy, those treated with highly active anti-biofilm (HAAB) agents (e.g., caspofungin) had significantly shorter post-CBSI hospital LOS than those treated with non-HAAB antifungal agents (e.g., fluconazole); this difference was confirmed when this analysis was conducted only among survivors. After matching, all the outcomes were still favorable for patients with non-biofilm-forming CBSI. Furthermore, the biofilm-forming CBSI was significantly associated with a matched excess risk for hospital death of 1.77 compared to non-biofilm-forming CBSI.

Conclusions

Our data show that biofilm growth by Candida has an adverse impact on clinical and economic outcomes of CBSI. Of note, better outcomes were seen for those CBSI patients who received HAAB antifungal therapy.