Adequacy of empirical antifungal therapy and effect on outcome among patients with invasive Candida species infections

Risk prediction for invasive candidiasis

Over past few years, treatment of invasive candidiasis (IC) has evolved from targeted therapy to prophylaxis, pre-emptive and empirical therapy. Numerous predisposing factors for IC have been grouped together in various combinations to design risk prediction models. These models in general have shown good negative predictive value, but poor positive predictive value. They are useful in selecting the population which is less likely to benefit from empirical antifungal therapy and thus prevent overuse of antifungal agents. Current article deals with various risk prediction models for IC and their external validation studies.

[Evaluation of the VITEK 2 system (AST-YSO1 cards) for antifungal susceptibility testing against different Candida species]

The aim of this investigation was to evaluate the results of antifungal susceptibility for various Candida species using the Vitek 2 semi-automated system (AST-YSO1 cards, bioMérieux), and to compare them with those obtained by the CLSI (Clinical and Laboratory Standards Institute) broth microdilution reference method (Document M27-A3,2008). The essential agreement (EA) was > 90%, except for Candida glabrata against voriconazole (VCZ); and for Candida krusei against fluconazole (FCZ). The overall categorical agreement (CA) was > 90% when FCZ was evaluated and 89.5% at 24h and 80.7% at 48 h for VCZ. The average time for obtaining results was 15.5h. Minor errors were 7.8% at 24h and 6.1% at 48 h for FCZ, and 10.5% at 24h and 19.3% at 48 h for VCZ. There was only one very major error for FCZ against Candida parapsilosis and no major errors were observed. For amphotericin B, only three isolates showed MICs ≥ 2 μg/ml. The Vitek 2 system detected the MIC value for various Candida species and showed excellent agreement with the reference method proposed by the CLSI.

Empirical antifungal therapy with an echinocandin in critically-ill patients: prospective evaluation of a pragmatic Candida score-based strategy in one medical ICU

Background

Invasive candidiasis (IC) is a life-threatening ICU-acquired infection. A strong correlation between time to antifungal therapy (AFT) administration and outcome has been established. Empirical therapy benefit should be balanced with the risk of echinocandin overuse. We assessed therefore a decision rule that aimed at guiding empirical therapy.

Methods

A 45-month prospective cohort study in a teaching medical ICU. All of the patients with suspected IC (uncontrolled sepsis despite broad spectrum antibiotics without any bacterial proven infection in patients with Candida score ≥ 3 points including multifocal Candida sp. colonization) were eligible. The primary endpoint was proven IC diagnosis (i.e., candidemia) following treatment onset. Timing of AFT administration was also investigated in those latter patients. Antifungal therapy step-down and discontinuation was done according to international guidelines in patients with candidemia. Otherwise, echinocandin discontinuation was encouraged in patients without proven IC, excepting when a clinical improvement was achieved without any other explanation that antifungals initiation (i.e., probable IC). In addition, a survival multivariate analysis using a Cox model was conducted.

Results

Fifty-one patients were given an echinocandin with respect to our decision rule. Among them, candidemia was diagnosed thereafter in 9 patients. Over the same period, antifungal therapy was triggered by candidemia announcement (i.e., definite therapy) in 12 patients who did not fulfill criteria for empirical therapy before. Time elapsed from candidemia onset to echinocandin therapy initiation was shortened (0.4 [0.5] vs. 2.4 [2.8] hours; p = 0.04) when it was given empirically. In addition, 18 patients clinically improved under empirical antifungal therapy without any obvious other explanation, despite IC remained unproven. Moreover, echinocandin exposure duration was independently related to survival in those patients. Over the same period, our predefined criteria for empirical therapy were overruled in 55 cases. None of them develop IC thereafter. Finally, Our decision rule allowed IC early recognition of proven/probable IC with sensitivity, specificity, positive and negative predictive value of 69.2%, 82.1%, 69.2% and 82.1%, respectively.

Conclusion

Implementation of pragmatic guidelines for empirical AFT based on CS and fungal colonization assessment could be useful in selecting patients who really benefit from an echinocandin.

Impact of therapeutic strategies on the prognosis of candidemia in the ICU

OBJECTIVES

To determine the epidemiology of Candida bloodstream infections, variables influencing mortality, and antifungal resistance rates in ICUs in Spain.

DESIGN

Prospective, observational, multicenter population-based study.

SETTING

Medical and surgical ICUs in 29 hospitals distributed throughout five metropolitan areas of Spain.

PATIENTS

Adult patients (≥ 18 yr) with an episode of Candida bloodstream infection during admission to any surveillance area ICU from May 2010 to April 2011.

INTERVENTIONS

Candida isolates were sent to a reference laboratory for species identification by DNA sequencing and susceptibility testing using the methods and breakpoint criteria promulgated by the European Committee on Antimicrobial Susceptibility Testing. Prognostic factors associated with early (0-7 d) and late (8-30 d) mortality were analyzed using logistic regression modeling.

MEASUREMENTS AND MAIN RESULTS

We detected 773 cases of candidemia, 752 of which were included in the overall cohort. Among these, 168 (22.3%) occurred in adult ICU patients. The rank order of Candida isolates was as follows: Candida albicans (52%), Candida parapsilosis (23.7%), Candida glabrata (12.7%), Candida tropicalis (5.8%), Candida krusei (4%), and others (1.8%). Overall susceptibility to fluconazole was 79.2%. Cumulative mortality at 7 and 30 days after the first episode of candidemia was 16.5% and 47%, respectively. Multivariate analysis showed that early appropriate antifungal treatment and catheter removal (odds ratio, 0.27; 95% CI, 0.08-0.91), Acute Physiology and Chronic Health Evaluation II score (odds ratio, 1.11; 95% CI, 1.04-1.19), and abdominal source (odds ratio, 8.15; 95% CI, 1.75-37.93) were independently associated with early mortality. Determinants of late mortality were age (odds ratio, 1.04; 95% CI, 1.01-1.07), intubation (odds ratio, 7.24; 95% CI, 2.24-23.40), renal replacement therapy (odds ratio, 6.12; 95% CI, 2.24-16.73), and primary source (odds ratio, 2.51; 95% CI, 1.06-5.95).

CONCLUSIONS

Candidemia in ICU patients is caused by non-albicans species in 48% of cases, C. parapsilosis being the most common among these. Overall mortality remains high and mainly related with host factors. Prompt adequate antifungal treatment and catheter removal could be critical to decrease early mortality.

An Observational Study on Early Empiric versus Culture-Directed Antifungal Therapy in Critically Ill with Intra-Abdominal Sepsis

Objective. To compare early empiric antifungal treatment with culture-directed treatment in critically ill patients with intra-abdominal sepsis. Methods. A prospective observational cohort study was conducted between August 2010 and July 2011, on SICU patients admitted after surgery for gastrointestinal perforation, bowel obstruction or ischemia, malignancy and anastomotic leakages. Patients who received antifungal treatment within two days of sepsis onset were compared to patients who received culture-directed antifungal treatment in terms of mortality rate and clinical improvement. Patients' demographics, comorbidities, severity-of-illness scores, and laboratory results were systematically collected and analysed. Results. Thirty-three patients received early empiric and 19 received culture-directed therapy. Of these, 30 from the early empiric group and 18 from culture-directed group were evaluable and analysed. Both groups had similar baseline characteristics and illness severity. Patients on empiric antifungal use had significantly lower 30-day mortality (P = 0.03) as well as shorter median time to clinical improvement (P = 0.025). Early empiric antifungal therapy was independently associated with survival beyond 30 days (OR 0.131, 95% CI: 0.018 to 0.966; P = 0.046). Conclusion. Early empiric antifungal therapy in surgical patients with intra-abdominal sepsis was associated with reduced mortality and warrants further evaluation in randomised controlled trials.

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.

Propargyl-linked antifolates are dual inhibitors of Candida albicans and Candida glabrata

Species of Candida, primarily C. albicans and with increasing prevalence, C. glabrata, are responsible for the majority of fungal bloodstream infections that cause morbidity, especially among immune compromised patients. While the development of new antifungal agents that target the essential enzyme, dihydrofolate reductase (DHFR), in both Candida species would be ideal, previous attempts have resulted in antifolates that exhibit inconsistencies between enzyme inhibition and antifungal properties. In this article, we describe the evaluation of pairs of propargyl-linked antifolates that possess similar physicochemical properties but different shapes. All of these compounds are effective at inhibiting the fungal enzymes and the growth of C. glabrata; however, the inhibition of the growth of C. albicans is shape-dependent with extended para-linked compounds proving more effective than compact, meta-linked compounds. Using crystal structures of DHFR from C. albicans and C. glabrata bound to lead compounds, 13 new para-linked compounds designed to inhibit both species were synthesized. Eight of these compounds potently inhibit the growth of both fungal species with three compounds displaying dual MIC values less than 1 μg/mL. Analysis of the active compounds shows that shape and distribution of polar functionality is critical in achieving dual antifungal activity.

Distinct inflammatory mediator patterns characterize infectious and sterile systemic inflammation in febrile neutropenic hematology patients

Background

Invasive infections and sterile tissue damage can both give rise to systemic inflammation with fever and production of inflammatory mediators. This makes it difficult to diagnose infections in patients who are already inflamed, e.g. due to cell and tissue damage. For example, fever in patients with hematological malignancies may depend on infection, lysis of malignant cells, and/or chemotherapy-induced mucosal damage. We hypothesized that it would be possible to distinguish patterns of inflammatory mediators characterizing infectious and non-infectious causes of inflammation, respectively. Analysis of a broad range of parameters using a multivariate method of pattern recognition was done for this purpose.

Methods

In this prospective study, febrile (>38°C) neutropenic patients (n = 42) with hematologic malignancies were classified as having or not having a microbiologically defined infection by an infectious disease specialist. In parallel, blood was analyzed for 116 biomarkers, and 23 clinical variables were recorded for each patient. Using O-PLS (orthogonal projection to latent structures), a model was constructed based on these 139 variables that could separate the infected from the non-infected patients. Non-discriminatory variables were discarded until a final model was reached. Finally, the capacity of this model to accurately classify a validation set of febrile neutropenic patients (n = 10) as infected or non-infected was tested.

Results

A model that could segregate infected from non-infected patients was achieved based on discrete differences in the levels of 40 variables. These variables included acute phase proteins, cytokines, measures of coagulation, metabolism, organ stress and iron turn-over. The model correctly identified the infectious status of nine out of ten subsequently recruited febrile neutropenic hematology patients.

Conclusions

It is possible to separate patients with infectious inflammation from those with sterile inflammation based on inflammatory mediator patterns. This strategy could be developed into a decision-making tool for diverse clinical applications.

Invasive candidiasis in intensive care unit; consensus statement from an Iranian panel of experts, July 2013

Invasive candidiasis (IC) is associated with high mortality in intensive care unit (ICU) patients. Timely diagnosis of this potentially fatal condition remains a challenge; on the other hand, the criteria for initiating empirical antifungal therapy in critically ill patients are not well defined in different patient population and ICU settings. Alongside the international guidelines, reaching regional and local consensus on diagnosis and management of IC in ICU setting is essential. This report summarizes our present status of IC management in ICU, considered by a group of Iranian experts in the fields of intensive care and infectious diseases. A round table of 17 experts was held to review the available data and discuss the optimal treatment strategies for IC in critical care setting. Comparative published data on the management of IC were analytically reviewed and the commonly asked questions about the management of IC in ICU were isolated. These questions were interactively discussed by the panel and audience responses were taken to consolidate point-to-point agreement with the panel arriving at consensus in many instances. The responses indicated that patients’ risk stratification, clinical discretion, fungal diagnostic techniques and the empirical therapy for IC are likely to save more patients. Treatment options were recommended to be based on the disease severity, prior azole exposure, and the presence of suspected azole-resistant Candida species. This report was reviewed, edited and discussed by all participants to include further evidence-based insights. The panel expects such endorsed recommendations to be soon formulated for implementation across the country.

Micafungin: an evidence-based review of its place in therapy

Invasive fungal infections have increased throughout the world. Many of these infections occur in patients with multiple comorbidities who are receiving medications with the potential for interactions with antifungal therapy that could lead to renal and hepatic dysfunction. The second marketed echinocandin, micafungin, was approved in 2005 for the treatment of esophageal candidiasis and prophylaxis of invasive Candida infections in patients undergoing hematopoietic stem cell transplantation. The indication for use was later expanded to include candidemia, acute disseminated candidiasis, Candida abscesses, and peritonitis. Like other echinocandins it is fungicidal against Candida species, including those that are polyene- and azole-resistant and fungistatic against Aspergillus species. Its formulation is by the intravenous route only and it is dosed once daily without a loading dose as 85% of the steady state concentration is achieved after three daily doses. It has a favorable tolerability profile with no significant drug interactions and does not need adjustment for renal or hepatic insufficiency.

An Italian consensus for invasive candidiasis management (ITALIC)

INTRODUCTION

Invasive candidiasis (IC) has primarily been studied in intensive care unit (ICU) patients, although, in reality, a vast majority of these infections occur outside of the ICU. The recent publication of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) guidelines also deal with the non-ICU population, but many uncertainties remain on the management of IC, particularly in non-critically ill patients.

METHODS

The Italian Society of Antimicrobial Therapy, Società Italiana di Terapia Antimicrobica (SITA), produced practical, hospital-wide recommendations on the management of Candida infection in non-immunocompromised patients in the hospital ward.

RESULTS AND DISCUSSION

Our focus is on patient stratification in terms of risk factors for IC and of clinical severity, emphasising a high index of suspicion to ensure early diagnosis, early treatment and de-escalation when a patient is clinically stable, in order to optimise resource allocation.

Candidemia in the critically ill: initial therapy and outcome in mechanically ventilated patients

Background

Mortality among critically ill patients with candidemia is very high. We sought to determine whether the choice of initial antifungal therapy is associated with survival among these patients, using need for mechanical ventilatory support as a marker of critical illness.

Methods

Cohort analysis of outcomes among mechanically ventilated patients with candidemia from the 24 North American academic medical centers contributing to the Prospective Antifungal Therapy (PATH) Alliance registry. Patients were included if they received either fluconazole or an echinocandin as initial monotherapy.

Results

Of 5272 patients in the PATH registry at the time of data abstraction, 1014 were ventilated and concomitantly had candidemia, with 689 eligible for analysis. 28-day survival was higher among the 374 patients treated initially with fluconazole than among the 315 treated with an echinocandin (66% versus 51%, P < .001). Initial fluconazole therapy remained associated with improved survival after adjusting for non-treatment factors in the overall population (hazard ratio .75, 95% CI .59–.96), and also among patients with albicans infection (hazard ratio .62, 95% CI .44–.88). While not statistically significant, fluconazole appeared to be associated with higher mortality among patients infected with glabrata (HR 1.13, 95% CI .70–1.84).

Conclusions

Among ventilated patients with candidemia, those receiving fluconazole as initial monotherapy were significantly more likely to survive than those treated with an echinocandin. This difference persisted after adjustment for non-treatment factors.

The "de-escalation concept" and antibiotic de-escalation: a missed opportunity?

"De-escalation therapy" is a term that suggests the need to reduce the spectrum or the number of antibiotics formerly prescribed for critical patients, upon clinical improvement and/or microorganism recovery. The major goal of this concept is the use of broad-spectrum antibiotic agents as initial drugs of choice for severe patients, instead of "reserving" the most potent agents after an inadequate clinical response, or after the microorganism is recovered. Despite possible commercial concerns and an unproven but possible relationship with enhancing global antibiotic use, the concept was correct and in accordance with scientific evidence. However, the "de-escalation" component of the concept is very seldom reported, and no large clinical trial on this issue is available until today. To definitely put in practice this concept, comparative large trials must be designed and sponsored to insert this strategy at the same level of evidence of wide initial empiric antibiotic treatments.

Treatment of invasive candidiasis in the elderly: a review

Fungi are major causes of infections among immunocompromised or hospitalized patients with serious underlying diseases and comorbidities. Candida species remain the most important cause of opportunistic infections worldwide, affecting predominantly patients over 65 years old, while they are considered to be the fourth most common cause of nosocomial bloodstream infections. The rapidly growing elderly population has specific physiological characteristics, which makes it susceptible to colonization and subsequent infection due to Candida species. Comorbidities and multidrug use should be taken into account any time the therapeutic regimen is under consideration. Different classes of antifungal drugs are available for the treatment of invasive fungal infections but echinocandins, apart from their activity against resistant strains (Candida glabrata and Candida krusei), seem to be safe, with limited adverse events and minimal drug-drug interactions in comparison to the other regimens. Therefore, these agents are strongly recommended when dealing with elderly patients suffering from an invasive form of Candida infection.

Comparative study of the prevalence of sepsis in patients admitted to dermatology and internal medicine wards

BACKGROUND

Sepsis is a common cause of morbidity and mortality among hospitalized patients. The prevalence of this condition has increased significantly in different parts of the world. Patients admitted to dermatology wards often have severe loss of skin barrier and use systemic corticosteroids, which favor the development of sepsis.

OBJECTIVES

To evaluate the prevalence of sepsis among patients admitted to a dermatology ward compared to that among patients admitted to an internal medicine ward.

METHODS

It is a cross-sectional, observational, comparative study that was conducted at Hospital Santa Casa de Belo Horizonte. Data were collected from all patients admitted to four hospital beds at the dermatology and internal medicine wards between July 2008 and July 2009. Medical records were analyzed for the occurrence of sepsis, dermatologic diagnoses, comorbidities, types of pathogens and most commonly used antibiotics.

RESULTS

We analyzed 185 medical records. The prevalence of sepsis was 7.6% among patients admitted to the dermatology ward and 2.2% (p = 0.10) among those admitted to the internal medicine ward. Patients with comorbidities, diabetes mellitus and cancer did not show a higher incidence of sepsis. The main agent found was Staphylococcus aureus, and the most commonly used antibiotics were ciprofloxacin and oxacillin. There was a significant association between sepsis and the use of systemic corticosteroids (p <0.001).

CONCLUSION

It becomes clear that epidemiological studies on sepsis should be performed more extensively and accurately in Brazil so that efforts to prevent and treat this serious disease can be made more effectively.

Rapid antifungal susceptibility testing by matrix-assisted laser desorption ionization-time of flight mass spectrometry analysis

The widespread use of antifungal agents, which is likely to expand with their enhanced availability, has promoted the emergence of drug-resistant strains. Antifungal susceptibility testing (AFST) is now an essential procedure for guiding appropriate antifungal therapy. Recently, we developed a matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS)-based method that enables the detection of fungal isolates with reduced echinocandin susceptibility, relying on the proteome changes that are detectable after a 15-h exposure of fungal cells to serial drug concentrations. Here, we describe a simplified version of this approach that facilitates discrimination of the susceptible and resistant isolates of Candida albicans after a 3-h incubation in the presence of "breakpoint" level drug concentrations of the echinocandin caspofungin (CSF). Spectra at concentrations of 0 (null), 0.03 (intermediate), and 32 (maximal) μg/ml of CSF were used to create individual composite correlation index (CCI) matrices for 65 C. albicans isolates, including 13 fks1 mutants. Isolates are then classified as susceptible or resistant to CSF if the CCI values of spectra at 0.03 and 32 μg/ml are higher or lower, respectively, than the CCI values of spectra at 0.03 and 0 μg/ml. In this way, the drug resistance of C. albicans isolates to echinocandin antifungals can be quickly assessed. Furthermore, the isolate categorizations determined using MALDI-TOF MS-based AFST (ms-AFST) were consistent with the wild-type and mutant FKS1 genotypes and the AFST reference methodology. The ms-AFST approach may provide a rapid and reliable means of detecting emerging antifungal resistance and accelerating the initiation of appropriate antifungal treatment.

[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.

Echinocandin and triazole antifungal susceptibility profiles for clinical opportunistic yeast and mold isolates collected from 2010 to 2011: application of new CLSI clinical breakpoints and epidemiological cutoff values for characterization of geographic and temporal trends of antifungal resistance

The SENTRY Antimicrobial Surveillance Program monitors global susceptibility and resistance rates of newer and established antifungal agents. We report the echinocandin and triazole antifungal susceptibility patterns for 3,418 contemporary clinical isolates of yeasts and molds. The isolates were obtained from 98 laboratories in 34 countries during 2010 and 2011. Yeasts not presumptively identified by CHROMagar, the trehalose test, or growth at 42°C and all molds were sequence identified using internal transcribed spacer (ITS) and 28S (yeasts) or ITS, translation elongation factor (TEF), and 28S (molds) genes. Susceptibility testing was performed against 7 antifungals (anidulafungin, caspofungin, micafungin, fluconazole, itraconazole, posaconazole, and voriconazole) using CLSI methods. Rates of resistance to all agents were determined using the new CLSI clinical breakpoints and epidemiological cutoff value criteria, as appropriate. Sequencing of fks hot spots was performed for echinocandin non-wild-type (WT) strains. Isolates included 3,107 from 21 Candida spp., 146 from 9 Aspergillus spp., 84 from Cryptococcus neoformans, 40 from 23 other mold species, and 41 from 9 other yeast species. Among Candida spp., resistance to the echinocandins was low (0.0 to 1.7%). Candida albicans and Candida glabrata that were resistant to anidulafungin, caspofungin, or micafungin were shown to have fks mutations. Resistance to fluconazole was low among the isolates of C. albicans (0.4%), Candida tropicalis (1.3%), and Candida parapsilosis (2.1%); however, 8.8% of C. glabrata isolates were resistant to fluconazole. Among echinocandin-resistant C. glabrata isolates from 2011, 38% were fluconazole resistant. Voriconazole was active against all Candida spp. except C. glabrata (10.5% non-WT), whereas posaconazole showed decreased activity against C. albicans (4.4%) and Candida krusei (15.2% non-WT). All agents except for the echinocandins were active against C. neoformans, and the triazoles were active against other yeasts (MIC90, 2 μg/ml). The echinocandins and triazoles were active against Aspergillus spp. (MIC90/minimum effective concentration [MEC90] range, 0.015 to 2 μg/ml), but the echinocandins were not active against other molds (MEC90 range, 4 to >16 μg/ml). Overall, echinocandin and triazole resistance rates were low; however, the fluconazole and echinocandin coresistance among C. glabrata strains warrants continued close surveillance.

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.

ESCMID* guideline for the diagnosis and management of Candida diseases 2012: non-neutropenic adult patients

This part of the EFISG guidelines focuses on non-neutropenic adult patients. Only a few of the numerous recommendations can be summarized in the abstract. Prophylactic usage of fluconazole is supported in patients with recent abdominal surgery and recurrent gastrointestinal perforations or anastomotic leakages. Candida isolation from respiratory secretions alone should never prompt treatment. For the targeted initial treatment of candidaemia, echinocandins are strongly recommended while liposomal amphotericin B and voriconazole are supported with moderate, and fluconazole with marginal strength. Treatment duration for candidaemia should be a minimum of 14 days after the end of candidaemia, which can be determined by one blood culture per day until negativity. Switching to oral treatment after 10 days of intravenous therapy has been safe in stable patients with susceptible Candida species. In candidaemia, removal of indwelling catheters is strongly recommended. If catheters cannot be removed, lipid-based amphotericin B or echinocandins should be preferred over azoles. Transoesophageal echocardiography and fundoscopy should be performed to detect organ involvement. Native valve endocarditis requires surgery within a week, while in prosthetic valve endocarditis, earlier surgery may be beneficial. The antifungal regimen of choice is liposomal amphotericin B +/- flucytosine. In ocular candidiasis, liposomal amphotericin B +/- flucytosine is recommended when the susceptibility of the isolate is unknown, and in susceptible isolates, fluconazole and voriconazole are alternatives. Amphotericin B deoxycholate is not recommended for any indication due to severe side effects.

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.

Optimizing antifungal choice and administration

BACKGROUND

The antifungal armamentarium includes a number of drug classes and agents within each class. Successful IFI management depends on optimal matching of drug choice with the individual patient and causative pathogen, and maximizing effectiveness of the selected drug through appropriate dosing and toxicity management.

OBJECTIVE

This review is intended to provide a brief overview of key factors involved in optimizing antifungal choice and administration for patients with invasive fungal infections (IFIs).

FINDINGS

Antifungals differ in spectrum of activity, and these differences are critical when selecting the antifungal most likely to provide success for a patient with an IFI. When the species has not yet been identified, an analysis of regional epidemiology and risk factors can provide clues as to the most likely pathogen. For severely immunocompromised patients, a fungicidal agent may be preferred over a fungistatic agent, although more research is needed in this area. Triazoles, particularly itraconazole and posaconazole, exhibit great interpatient pharmacokinetic variability related to absorption. Steps can be taken to maximize absorption when using these agents. Voriconazole concentration is affected by polymorphisms in the major metabolic enzyme, cytochrome P450 2C19. Triazoles, and to a lesser extent other antifungals, are also subject to drug-drug interactions, which needs to be considered when selecting a particular antifungal agent for use in a severely ill patient on polypharmacy. Therapeutic drug monitoring may be a useful adjunct for patients receiving itraconazole, voriconazole, or posaconazole. When the IFI involves a pharmacologically protected site, such as the central nervous system (CNS) or eye, 5-fluorocytosine, fluconazole, or voriconazole are generally preferred. Echinocandin penetration is typically inadequate for IFIs of the CNS or eye. Antifungal agents also differ in their toxicity profiles, and these issues also need to be considered and managed when making an antifungal choice.

CONCLUSION

Successful management of IFIs relies in part on the accurate selection of an antifungal agent for the infection. Drug characteristics can help in the selection of drug therapy. These characteristics include the drug's spectrum of activity, pharmacokinetics, pharmacodynamics, toxicity profile, and distribution to the infection site. Matching the drug profile to the patient and fungal species contribute to optimal management of infection.

Invasive candidiasis in intensive care units in China: a multicentre prospective observational study

OBJECTIVES

To describe the epidemiology, microbiology and management of invasive Candida infection (ICI) in intensive care units (ICUs) in China.

METHODS

A multicentre, prospective, observational study in 67 hospital ICUs across China. Patients were ≥18 years old with clinical signs of infection and at least one of the following diagnostic criteria: (i) histopathological, cytopathological or microscopic confirmation of yeast cells from a normally sterile site; (ii) at least one peripheral blood culture positive for Candida; and (iii) positive Candida culture from a normally sterile site. The China-SCAN study is registered with ClinicalTrials.gov (NCT T01253954).

RESULTS

ICI incidence was 0.32% (306 patients/96,060 ICU admissions) and median time between ICU admission and diagnosis was 10.0 days. Candida albicans was the most prevalent single isolate (41.8% of patients), although non-albicans species accounted for the majority of infections. Diagnostic confirmation was based solely on at least one positive blood culture in 290 (94.8%) cases. Treatment was initiated after diagnostic confirmation in 166/268 (61.9%) patients. Triazoles (62.7%) and echinocandins (34.2%) were the most commonly used antifungal agents; first-line therapy was typically fluconazole (37.7%). The median duration of antifungal therapy was 14 days. The mortality rate was 36.6% (112/306); the median time between diagnosis and death was 14.5 days. Mortality was higher in older individuals, those with solid tumours, those with recent invasive mechanical ventilation and those with a higher sequential organ failure assessment score at diagnostic confirmation. Susceptibility to first-line antifungals was associated with lower mortality than dose-dependent susceptibility or complete resistance (P=0.008).

CONCLUSIONS

More infections were caused by non-albicans than Candida albicans strains. The majority of patients were treated only after diagnostic confirmation, rather than empirically. First-line antifungal susceptibility was associated with lower mortality.

Comparison of three different commercial PCR assays for the detection of pathogens in critically ill sepsis patients

INTRODUCTION

The high mortality rate associated with sepsis necessitates a timely identification of the causative organism in order to optimize antimicrobial therapy. PCR assays are increasingly being used for this purpose. The aim of this study was to compare three commercially available PCR systems for the diagnosis of systemic infections.

PATIENTS AND METHODS

In a prospective observational study, a broad-range (SepsiTest®; Molzym, Bremen, Germany) and two multiplex PCR assays (VYOO®; SIRS-Lab, Jena, Germany and LightCycler® SeptiFast; Roche, Mannheim, Germany) were compared to blood cultures with respect to the clinical course of 50 critically ill patients with sepsis, severe sepsis or septic shock.

RESULTS

Pathogens were detected by PCR in 12 % (SepsiTest®), 10 % (VYOO®) and 14 % (LightCycler® SeptiFast) of samples and in 26 % by blood culture. Negative results were obtained using all four methods in 32 samples (64 %) and 3 (6 %) samples were positive in all tests. Upon consideration of additional diagnostic findings and the clinical course, eight (16 %) of the positive blood culture results were deemed clinically relevant. All three PCR assays could also identify the causative organism (or a specific gene thereof) in three of these eight positive blood cultures, whereas for five of the eight, all three PCR assays were negative. In one patient with a negative blood culture, the SepsiTest®, VYOO® and LightCycler® SeptiFast assays were positive for Streptococcus species. The PCR assays appeared to be less susceptible than blood cultures to false-positive results arising from contamination with coagulase-negative staphylococcal organisms.

CONCLUSION

There was some variability between the three PCR assays tested and the corresponding blood cultures with regards to the type of pathogen detected. The three PCR assays appeared to be less susceptible to false-positive results than blood cultures.

In vitro susceptibilities of yeast species to fluconazole and voriconazole as determined by the 2010 National China Hospital Invasive Fungal Surveillance Net (CHIF-NET) study

We conducted active, laboratory-based surveillance for isolates from patients with invasive infections across China from August 2009 to July 2010. DNA sequencing methods were used to define species, and susceptibility to fluconazole and voriconazole was determined by the Clinical and Laboratory Standards Institute M44-A2 disk diffusion method but using up-to-date clinical breakpoints or epidemiological cutoff values. Candida spp. made up 90.5% of the 814 yeast strains isolated, followed by Cryptococcus neoformans (7.7%) and other non-Candida yeast strains (1.7%). Bloodstream isolates made up 42.9% of the strains, isolates from ascitic fluid made up 22.1%, but pus/tissue specimens yielded yeast strains in <5% of the cases. Among the Candida isolates, Candida albicans was the most common species from specimens other than blood (50.1%) but made up only 23% of the bloodstream isolates (P < 0.001). C. parapsilosis complex species were the most common Candida isolates from blood (33.2%). Uncommon bloodstream yeast strains included Trichosporon spp., C. pelliculosa, and the novel species C. quercitrusa, reported for the first time as a cause of candidemia. Most (>94%) of the isolates of C. albicans, C. tropicalis, and the C. parapsilosis complex were susceptible to fluconazole and voriconazole, as were all of the Trichosporon strains; however, 12.2% of the C. glabrata sensu stricto isolates were fluconazole resistant and 17.8% had non-wild-type susceptibility to voriconazole. Seven C. tropicalis strains were cross-resistant to fluconazole and voriconazole; six were from patients in the same institution. Resistance to fluconazole and voriconazole was seen in 31.9% and 13.3% of the uncommon Candida and non-Candida yeast strains, respectively. Causative species and azole susceptibility varied with the geographic region. This study provided clinically useful data on yeast strains and their antifungal susceptibilities in China.

Aggressive versus conservative initiation of antimicrobial treatment in critically ill surgical patients with suspected intensive-care-unit-acquired infection: a quasi-experimental, before and after observational cohort study

BACKGROUND

Antimicrobial treatment in critically ill patients can either be started as soon as infection is suspected or after objective data confirm an infection. We postulated that delaying antimicrobial treatment of patients with suspected infections in the surgical intensive care unit (SICU) until objective evidence of infection had been obtained would not worsen patient mortality.

METHODS

We did a 2-year, quasi-experimental, before and after observational cohort study of patients aged 18 years or older who were admitted to the SICU of the University of Virginia (Charlottesville, VA, USA). From Sept 1, 2008, to Aug 31, 2009, aggressive treatment was used: patients suspected of having an infection on the basis of clinical grounds had blood cultures sent and antimicrobial treatment started. From Sept 1, 2009, to Aug 31, 2010, a conservative strategy was used, with antimicrobial treatment started only after objective findings confirmed an infection. Our primary outcome was in-hospital mortality. Analyses were by intention to treat.

FINDINGS

Admissions to the SICU for the first and second years were 762 and 721, respectively, with 101 patients with SICU-acquired infections during the aggressive year and 100 patients during the conservative year. Compared with the aggressive approach, the conservative approach was associated with lower all-cause mortality (13/100 [13%] vs 27/101 [27%]; p=0·015), more initially appropriate therapy (158/214 [74%] vs 144/231 [62%]; p=0·0095), and a shorter mean duration of therapy (12·5 days [SD 10·7] vs 17·7 [28·1]; p=0·0080). After adjusting for age, sex, trauma involvement, acute physiology and chronic health evaluation (APACHE) II score, and site of infection, the odds ratio for the risk of mortality in the aggressive therapy group compared with the conservative therapy group was 2·5 (95% CI 1·5-4·0).

INTERPRETATION

Waiting for objective data to diagnose infection before treatment with antimicrobial drugs for suspected SICU-acquired infections does not worsen mortality and might be associated with better outcomes and use of antimicrobial drugs.

FUNDING

National Institutes of Health.

β-D-glucan surveillance with preemptive anidulafungin for invasive candidiasis in intensive care unit patients: a randomized pilot study

BACKGROUND

Invasive candidiasis (IC) is a devastating disease. While prompt antifungal therapy improves outcomes, empiric treatment based on the presence of fever has little clinical impact. Β-D-Glucan (BDG) is a fungal cell wall component detectable in the serum of patients with early invasive fungal infection (IFI). We evaluated the utility of BDG surveillance as a guide for preemptive antifungal therapy in at-risk intensive care unit (ICU) patients.

METHODS

Patients admitted to the ICU for ≥ 3 days and expected to require at least 2 additional days of intensive care were enrolled. Subjects were randomized in 3:1 fashion to receive twice weekly BDG surveillance with preemptive anidulafungin in response to a positive test or empiric antifungal treatment based on physician preference.

RESULTS

Sixty-four subjects were enrolled, with 1 proven and 5 probable cases of IC identified over a 2.5 year period. BDG levels were higher in subjects with proven/probable IC as compared to those without an IFI (117 pg/ml vs. 28 pg/ml; p<0.001). Optimal assay performance required 2 sequential BDG determinations of ≥ 80 pg/ml to define a positive test (sensitivity 100%, specificity 75%, positive predictive value 30%, negative predictive value 100%). In all, 21 preemptive and 5 empiric subjects received systemic antifungal therapy. Receipt of preemptive antifungal treatment had a significant effect on BDG concentrations (p< 0.001). Preemptive anidulafungin was safe and generally well tolerated with excellent outcome.

CONCLUSIONS

BDG monitoring may be useful for identifying ICU patients at highest risk to develop an IFI as well as for monitoring treatment response. Preemptive strategies based on fungal biomarkers warrant further study.

TRIAL REGISTRATION

Clinical Trials.gov NCT00672841.

Empiric antifungal therapy and outcomes in extremely low birth weight infants with invasive candidiasis

OBJECTIVE

To assess the impact of empiric antifungal therapy for invasive candidiasis on subsequent outcomes in premature infants.

STUDY DESIGN

This was a cohort study of infants with a birth weight ≤ 1000 g receiving care at Neonatal Research Network sites. All infants had at least one positive culture for Candida. Empiric antifungal therapy was defined as receipt of a systemic antifungal on the day of or the day before the first positive culture for Candida was drawn. We created Cox proportional hazards and logistic regression models stratified on propensity score quartiles to determine the effect of empiric antifungal therapy on survival, time to clearance of infection, retinopathy of prematurity, bronchopulmonary dysplasia, end-organ damage, and neurodevelopmental impairment (NDI).

RESULTS

A total of 136 infants developed invasive candidiasis. The incidence of death or NDI was lower in infants who received empiric antifungal therapy (19 of 38; 50%) compared with those who had not (55 of 86; 64%; OR, 0.27; 95% CI, 0.08-0.86). There was no significant difference between the groups for any single outcome or other combined outcomes.

CONCLUSION

Empiric antifungal therapy was associated with increased survival without NDI. A prospective randomized trial of this strategy is warranted.

Progress in antifungal susceptibility testing of Candida spp. by use of Clinical and Laboratory Standards Institute broth microdilution methods, 2010 to 2012

Antifungal susceptibility testing of Candida has been standardized and refined and now may play a useful role in managing Candida infections. Important new developments include validation of 24-h reading times for all antifungal agents and the establishment of species-specific epidemiological cutoff values (ECVs) for the systemically active antifungal agents and both common and uncommon species of Candida. The clinical breakpoints (CBPs) for fluconazole, voriconazole, and the echinocandins have been revised to provide species-specific interpretive criteria for the six most common species. The revised CBPs not only are predictive of clinical outcome but also provide a more sensitive means of identifying those strains with acquired or mutational resistance mechanisms. This brief review serves as an update on the new developments in the antifungal susceptibility testing of Candida spp. using Clinical and Laboratory Standards Institute (CLSI) broth microdilution (BMD) methods.

Echinocandin resistance due to simultaneous FKS mutation and increased cell wall chitin in a Candida albicans bloodstream isolate following brief exposure to caspofungin

Echinocandins are first-line agents for treating severe invasive candidiasis. Glucan synthase gene (FKS1) mutations lead to echinocandin resistance but the role of enhanced chitin expression is not well recognized in clinical isolates. We report a case of bloodstream Candida albicans infection with both Fks1 hotspot mutation and elevated cell wall chitin.

Assessment of accuracy of identification of pathogenic yeasts in microbiology laboratories in the United kingdom

Rapid, accurate identification of yeast isolates from clinical samples has always been important given their innately variable antifungal susceptibility profiles. Recently, this has become paramount with the proposed introduction of species-specific interpretive breakpoints for MICs obtained in yeast antifungal susceptibility tests (M. A. Pfaller, D. Andes, D. J. Diekema, A. Espinel-Ingroff, D. Sheehan, and CLSI Subcommittee for Antifungal Susceptibility Testing, Drug Resist. Updat. 13:180-195, 2010). Here, we present the results of a 12-month evaluation of the accuracy of identifications that accompany yeast isolates submitted to the Mycology Reference Laboratory (United Kingdom) for either confirmation of identity or susceptibility testing. In total, 1,781 yeast isolates were analyzed, and the robustness of prior identifications obtained in microbiology laboratories throughout the United Kingdom was assessed using a combination of culture on chromogenic agar, morphology on cornmeal agar, and molecular identification by pyrosequencing. Over 40% of isolates (755) were submitted without any suggested identification. Of those isolates with a prior identification, 100 (9.7%) were incorrectly identified. Error rates ranged from 5.2% (for organisms submitted for antifungal susceptibility testing) to 18.2% (for organisms requiring confirmation of identity) and varied in a strictly species-specific manner. At least 50% of identification errors would be likely to affect interpretation of MIC data, with a possible impact on patient management. In addition, 2.3% of submitted cultures were found to contain mixtures of at least two yeast species. The vast majority of mixtures had gone undetected in the referring laboratory and would have impacted the interpretation of antifungal susceptibility profiles and patient management. Some of the more common misidentifications are discussed according to the identification method employed, with suggestions for avoiding such misinterpretations.

[Clinical features of critically ill patients with invasive fungal infection]

BACKGROUND

Invasive fungal infection (IFI) is an entity that encompasses different types of infections caused by different types of those fungi pathogenic for humans. In the setting of critically ill patients with multiple and often-concurrent risk factors and comorbidities the most common are those caused by the Candida and Aspergillus species. Among the characteristics of IFI in critically ill patients, three aspects can be highlighted: those related to the host (e.g.: risk factors, clinical severity), those related with the pathogen (sensitivity, virulence), or those concerning antifungal treatment (spectrum, features PK / PD, safety, interactions). The fungus that most often causes an IFI in critically ill patients is Candida; the most common type infections are candidemia, Candida peritonitis and catheter-related infections. In recent years new antifungal treatments have expanded the therapeutic options, with echinocandins as a clear choice, often the first in the latest guidelines in critically ill patients with IFI.

CASE REPORT

We report the case of a critically ill patient having the most common risk factors, multiple organ dysfunction and development of an IFI. The complexity of establishing an antifungal treatment from the moment of its inception, its setting, and the considerations of the different therapeutic possibilities according to organ dysfunction of the patient are discussed. The antifungal treatment options mentioned in the current guidelines and recommendations are also evaluated.

CONCLUSIONS

The most common fungal infection in critically ill patients is invasive candidiasis, with candidemia or candida peritonitis being the most frequent clinical presentations. Candins have brought new possibilities for treating these complex patients due to their good safety profile and clinical efficacy.

An observational study on the epidemiological and mycological profile of Candidemia in ICU patients

Background

This study aimed to analyze the epidemiological and mycological profile of candidemia in intensive care unit (ICU) patients attending a tertiary care teaching hospital in the Himalayan region of northern India.

Material/Methods

A 15-bed medico-surgical ICU and a 5-bed pediatric ICU. Ninety-one consecutively admitted ICU patients were screened for the presence of candidemia by performing blood cultures at periodic intervals.

Results

The recovered Candida isolates were speciated and subjected to antifungal susceptibility testing using standard procedures. Forty-one of the recruited patients (45%) were found to be candidemic, with the majority of patients being in the extremes of age (13 neonates and 15 >65 years of age). Four risk factors were found to be significantly associated with the occurrence of candidemia in our patients – a period of hospitalization exceeding 7 days (p=0.0008), previous use of antibiotics (p=0.001), presence of chronic renal failure (p=0.003), and ongoing cancer chemotherapy (p= 0.041). Ninety-six Candida isolates were recovered from the 41 culture-positive patients, with Candida albicans being the commonest isolate recovered (n=75, 78.1%), followed by Candida tropicalis (n=15, 16%), and Candida glabrata (n=6, 6.5%). Fluconazole resistance was observed among 26% of all Candida isolates and 17.3% of C. albicans isolates.

Conclusions

Contrary to the majority of recent reports, species shift towards non-albicans candidemia has not been observed in our center, though the prevalence of azole resistance is alarmingly high even among the C. albicans isolates.

Clinical efficacy and safety of intravenous itraconazole in the management of invasive candidiasis in patients of surgery and critical care

Although itraconazole exhibits potent activity against Candida species, there have been few studies examining the use of intravenous itraconazole in the treatment of invasive candidiasis. A nationwide multicenter clinical study was conducted to evaluate the efficacy and safety of intravenous itraconazole in the management of invasive candidiasis, including non-albicans Candida species, in non-neutropenic patients undergoing surgery and critical care. Between September 2007 and August 2009, patients with proven and presumed candidiasis were enrolled at 22 participating institutions. Patients with presumed candidiasis had a deep-body temperature of 37.8°C or higher and were positive for serum β-D: -glucan or two or more colonization sites of Candida species. The main exclusion criterion was severe renal impairment (creatinine clearance <30 ml/min). The primary efficacy analysis was based on clinical and microbiological responses 5-10 days after the end of treatment, assessed by an independent data review committee. Of the 60 patients enrolled, 49 were included in the modified intention-to-treat population; 31 patients received a definitive diagnosis and 18 patients a presumed diagnosis. Intravenous itraconazole was used as first-line therapy to treat 39 patients and as second-line therapy for 10 patients. The isolated species included Candida albicans (25 strains with definitive diagnosis and 17 with presumed diagnosis) and non-albicans species (16 and 10, respectively). Treatment was successful in 61.5% patients (65.5% in first-line and 50.0% in second-line therapy); 60% of proven invasive candidiasis (IC) patients were judged as successful compared with 63.2% of presumed candidiasis patients. Eradication rate was 63.6% for C. albicans and 71.4% for C. glabrata. Adverse effects occurred in 9 of 60 patients (15.0%), commonly impaired liver function. The clinical efficacy and safety of intravenous itraconazole were suggested in the management of proven and presumed candidiasis including C. glabrata in non-neutropenic patients. The status of intravenous itraconazole in the Japanese guideline warrants reconsideration.

Invasive fungal infections in patients with cancer in the Intensive Care Unit

Invasive fungal infections (IFIs) have emerged as a major cause of morbidity and mortality amongst critically ill patients. Cancer patients admitted to the Intensive Care Unit (ICU) have multiple risk factors for IFIs. The vast majority of IFIs in the ICU are due to Candida spp. The incidence of invasive candidiasis (IC) has increased over recent decades, especially in the ICU. A shift in the distribution of Candida spp. from Candida albicans to non-albicans Candida spp. has been observed both in ICUs and oncology units in the last two decades. Timely diagnosis of IC remains a challenge despite the introduction of new microbiology techniques. Delayed initiation of antifungal therapy is associated with increased mortality. Therefore, prediction rules have been developed and validated prospectively in order to identify those ICU patients at high risk for IC and likely to benefit from early treatment. These rules, however, have not been validated in cancer patients. Similarly, major clinical studies on the efficacy of newer antifungals typically do not include cancer patients. Despite the introduction of more potent and less toxic antifungals, mortality from IFIs amongst cancer patients remains high. In recent years, aspergillosis and mucormycosis have also emerged as significant causes of morbidity and mortality amongst ICU patients with haematological cancer.

Evaluation of "Candida score" in critically ill patients: a prospective, multicenter, observational, cohort study

Introduction

Although prompt initiation of appropriate antifungal therapy is essential for the control of invasive Candida infections and an improvement of prognosis, early diagnosis of invasive candidiasis remains a challenge and criteria for starting empirical antifungal therapy in ICU patients are poorly defined. Some scoring systems, such as the "Candida score" could help physicians to differentiate patients who could benefit from early antifungal treatment from those for whom invasive candidiasis is highly improbable. This study evaluated the performance of this score in a cohort of critically ill patients.

Methods

A prospective, observational, multicenter, cohort study was conducted from January 2010 to March 2011 in five intensive care units in Nord-Pas de Calais, an area from North of France. All patients exhibiting, on ICU admission or during their ICU stay, a hospital-acquired severe sepsis or septic shock could be included in this study. The data collected included patient characteristics on ICU admission and at the onset of severe sepsis or septic shock. The "Candida score" was calculated at the onset of sepsis or shock. The incidence of invasive candidiasis was determined and its relationship with the value of the "Candida score" was studied.

Results

Ninety-four patients were studied. When severe sepsis or shock occurred, 44 patients had a score = 2, 29 patients had a score = 3, 17 patients had a score = 4, and 4 patients had a score = 5. Invasive candidiasis was observed in five (5.3%) patients. One patient had candidemia, three patients had peritonitis, and one patient had pleural infection. The rates of invasive candidiasis was 0% in patients with score = 2 or 3, 17.6% in patients with score = 4, and 50% in patients with score = 5 (p < 0.0001).

Conclusions

Our results confirm that the "Candida score" is an interesting tool to differentiate among ICU patients who exhibit hospital-acquired severe sepsis or septic shock those would benefit from early antifungal treatment (score > 3) from those for whom invasive candidiasis is highly improbable (score ≤ 3).

Multidisciplinary approach to the treatment of invasive fungal infections in adult patients. Prophylaxis, empirical, preemptive or targeted therapy, which is the best in the different hosts?

The high morbidity, mortality, and health care costs associated with invasive fungal infections, especially in the critical care setting and immunocompromised host, have made it an excellent target for prophylactic, empiric, and preemptive therapy interventions principally based on early identification of risk factors. Early diagnosis and treatment are associated with a better prognosis. In the last years there have been important developments in antifungal pharmacotherapy. An approach to the new diagnosis tools in the clinical mycology laboratory and an analysis of the use new antifungal agents and its application in different clinical situations has been made. Furthermore, an attempt of developing a state of the art in each clinical scenario (critically ill, hematological, and solid organ transplant patients) has been performed, trying to choose the best strategy for each clinical situation (prophylaxis, pre-emptive, empirical, or targeted therapy). The high mortality rates in these settings make mandatory the application of early de-escalation therapy in critically ill patients with fungal infection. In addition, the possibility of antifungal combination therapy might be considered in solid organ transplant and hematological patients.

Early diagnosis of candidemia in intensive care unit patients with sepsis: a prospective comparison of (1→3)-β-D-glucan assay, Candida score, and colonization index

Introduction

The culture-independent serum (1→3)-β-D-glucan (BG) detection test may allow early diagnosis of invasive fungal disease, but its clinical usefulness needs to be firmly established. A prospective single-center observational study was conducted to compare the diagnostic value of BG assay, Candida score (CS), and colonization index in intensive care unit (ICU) patients at risk for Candida sepsis.

Methods

Of 377 patients, consecutively admitted to ICU for sepsis, 95 patients having an ICU stay of more than five days were studied. Blood specimens for fungal culture and BG measurement were obtained at the onset of clinical sepsis. For CS and colonization index calculations, surveillance cultures for Candida growth, and/or clinical data were recorded.

Results

Sixteen (16.8%) patients were diagnosed with proven invasive fungal infection, 14 with candidiasis (13 candidemia and 1 mediastinitis) and 2 with pulmonary aspergillosis or fusariosis. Of 14 invasive Candida-infection patients, 13 had a serum sample positive for BG, 10 had a CS value ≥3, and 7 a colonization index ≥0.5. In the 12 candidemic patients, a positive BG result was obtained 24 to 72 hrs before a culture-documented diagnosis of invasive candidiasis. The positive and negative predictive values for the BG assay were higher than those of CS and colonization index (72.2% versus 57.1% and 27.3%; and 98.7% versus 97.2% and 91.7%, respectively).

Conclusions

A single-point BG assay based on a blood sample drawn at the sepsis onset, alone or in combination withCS, may guide the decision to start antifungal therapy early in patients at risk for Candida infection.

Validation of 24-hour flucytosine MIC determination by comparison with 48-hour determination by the Clinical and Laboratory Standards Institute M27-A3 broth microdilution reference method

Flucytosine and itraconazole are the only antifungal agents for which the Clinical Laboratory and Standards Institute recommendations include MIC breakpoint readings at 48 h only. Here we show good essential and categorical agreement between the flucytosine MIC readings at 48 and 24 h for Candida species.

Candida bloodstream infections in intensive care units: analysis of the extended prevalence of infection in intensive care unit study

OBJECTIVES

To provide a global, up-to-date picture of the prevalence, treatment, and outcomes of Candida bloodstream infections in intensive care unit patients and compare Candida with bacterial bloodstream infection.

DESIGN

A retrospective analysis of the Extended Prevalence of Infection in the ICU Study (EPIC II). Demographic, physiological, infection-related and therapeutic data were collected. Patients were grouped as having Candida, Gram-positive, Gram-negative, and combined Candida/bacterial bloodstream infection. Outcome data were assessed at intensive care unit and hospital discharge.

SETTING

EPIC II included 1265 intensive care units in 76 countries.

PATIENTS

Patients in participating intensive care units on study day.

INTERVENTIONS

None.

MEASUREMENT AND MAIN RESULTS

Of the 14,414 patients in EPIC II, 99 patients had Candida bloodstream infections for a prevalence of 6.9 per 1000 patients. Sixty-one patients had candidemia alone and 38 patients had combined bloodstream infections. Candida albicans (n = 70) was the predominant species. Primary therapy included monotherapy with fluconazole (n = 39), caspofungin (n = 16), and a polyene-based product (n = 12). Combination therapy was infrequently used (n = 10). Compared with patients with Gram-positive (n = 420) and Gram-negative (n = 264) bloodstream infections, patients with candidemia were more likely to have solid tumors (p < .05) and appeared to have been in an intensive care unit longer (14 days [range, 5-25 days], 8 days [range, 3-20 days], and 10 days [range, 2-23 days], respectively), but this difference was not statistically significant. Severity of illness and organ dysfunction scores were similar between groups. Patients with Candida bloodstream infections, compared with patients with Gram-positive and Gram-negative bloodstream infections, had the greatest crude intensive care unit mortality rates (42.6%, 25.3%, and 29.1%, respectively) and longer intensive care unit lengths of stay (median [interquartile range]) (33 days [18-44], 20 days [9-43], and 21 days [8-46], respectively); however, these differences were not statistically significant.

CONCLUSION

Candidemia remains a significant problem in intensive care units patients. In the EPIC II population, Candida albicans was the most common organism and fluconazole remained the predominant antifungal agent used. Candida bloodstream infections are associated with high intensive care unit and hospital mortality rates and resource use.

Optimizing antimicrobial therapy in sepsis and septic shock

Every patient with sepsis and septic shock must be evaluated thoroughly at presentation before the initiation of antibiotic therapy. However, in most situations, an abridged initial assessment focusing on critical diagnostic and management planning elements is sufficient. Intravenous antibiotics should be administered as early as possible, and always within the first hour of recognizing severe sepsis and septic shock. Broad-spectrum antibiotics must be selected with one or more agents active against likely bacterial or fungal pathogens and with good penetration into the presumed source. Antimicrobial therapy should be reevaluated daily to optimize efficacy, prevent resistance, avoid toxicity, and minimize costs. Consider combination therapy in Pseudomonas infections, and combination empiric therapy in neutropenic patients. Combination therapy should be continued for no more than 3 to 5 days and de-escalation should occur following availability of susceptibilities. The duration of antibiotic therapy typically is limited to 7 to 10 days; longer duration is considered if response is slow, if there is inadequate surgical source control, or in the case of immunologic deficiencies. Antimicrobial therapy should be stopped if infection is not considered the etiologic factor for a shock state.