Multicenter randomized trial of fluconazole versus amphotericin B for treatment of candidemia in non-neutropenic patients. Canadian Candidemia Study Group

Emerging azole antifungals

Systemic and superficial fungal infections have progressively emerged over the past few decades as an increasing cause of human disease, especially in the immunocompromised host. Control of fungal disease has proved difficult because few risk factors are potentially preventable; the population at highest risk for fungal disease, the immunocompromised patient, has been steadily increasing. There is a clear need for additional safe and effective therapeutic agents for the treatment of systemic fungal disease. A new generation of triazoles that includes voriconazole, posaconazole, ravuconazole and albaconazole has emerged and are presently in different phases of clinical investigation. These new triazoles have demonstrated a broad spectrum of activity, in particular against fungal pathogens previously resistant to previously available antifungals. This review highlights the emerging azole antifungals, both those available and in clinical development, and discusses their prospects for the future.

Tratamiento de las infecciones fúngicas invasoras

Invasive fungal infections have increased progressively in the last decades, producing elevated morbidity and mortality. In recent years, there have been numerous advances in the treatment of these diseases, with the introduction of new drugs in clinical practice and the information derived from several types of studies. This has improved the prognosis of some invasive fungal infections and increased the therapeutic options in various clinical situations. This new knowledge must be assessed to determine its application in clinical practice, taking into account available scientific evidence and clinical experience. With this aim, the Andalusian Society of Infectious Diseases has developed this consensus document containing recommendations for the treatment of the invasive fungal infections.

Antifungal therapy: lessons learned over the past 27 years

As principal investigator of the National Institute of Allergy and Infectious Diseases-sponsored Mycoses Study Group for the past 27 years, I have been fortunate to play a role in the many advances in the field of clinical mycology and antifungal therapy. For the Finland lecture, I will briefly discuss the development of the Mycoses Study Group, provide an overview of the currently available antifungal agents, and describe advances and lessons related to the treatment and management of cryptococcal meningitis (the most common form of fungal meningitis), 3 important endemic mycoses (namely, blastomycosis, histoplasmosis, and coccidioidomycosis), candidemia and invasive candidiasis (the most common forms of nosocomial fungal disease), and invasive aspergillosis (the most common form of invasive mould disease). My concluding remarks will address the increasing hurdles and challenges, as well as the rewards, facing investigators who focus on clinical trials.

Pharmacodynamics of caspofungin in a murine model of systemic candidiasis: importance of persistence of caspofungin in tissues to understanding drug activity

Pharmacokinetic and pharmacodynamic studies were conducted in a murine model of systemic candidiasis to determine the pharmacodynamic parameter linked with caspofungin efficacy. Additional studies defined the importance of persistent tissue drug concentrations to treatment outcome. The pharmacokinetics of caspofungin were determined in the serum and kidneys of infected mice over 96 h. Population pharmacokinetic analysis demonstrated a serum terminal half-life (t(1/2)) for caspofungin of 20.2 h when only serum concentrations were considered, but the terminal t(1/2) increased to 59.2 h when serum and kidney concentration-time data were co-modeled. In dose-range studies, the dose-response effect was well described by an inhibitory sigmoid curve for the exposure-effect killing caused by the drug (r2 > 0.96; P << 0.001). In dose-fractionation studies, fungal counts in kidneys were not statistically different for total doses given as one, two, or four equally divided doses over 96 h, indicating that the area under the concentration-time curve/MIC is the pharmacodynamic parameter that predicts caspofungin efficacy in our infection model. In a separate study, mice infected with Candida albicans 24 h after serum concentrations of caspofungin fell below the MIC for the fungal isolate had significant reductions in fungal densities in their kidneys compared with the growth of fungi in the kidneys of untreated controls (P = 0.005). This in vivo biological assay demonstrates that therapeutic concentrations of caspofungin persist at the site of infection in kidney tissue well after serum concentrations fall below the MIC, underscoring the primacy of caspofungin levels in tissues on determining treatment outcome.

Fluconazole for the management of invasive candidiasis: where do we stand after 15 years?

Candida spp. are responsible for most of the fungal infections in humans. Available since 1990, fluconazole is well established as a leading drug in the setting of prevention and treatment of mucosal and invasive candidiasis. Fluconazole displays predictable pharmacokinetics and an excellent tolerance profile in all groups, including the elderly and children. Fluconazole is a fungistatic drug against yeasts and lacks activity against moulds. Candida krusei is intrinsically resistant to fluconazole, and other species, notably Candida glabrata, often manifest reduced susceptibility. Emergence of azole-resistant strains as well as discovery of new antifungal drugs (new triazoles and echinocandins) have raised important questions about its use as a first line drug. The aim of this review is to summarize the main available data on the position of fluconazole in the prophylaxis or curative treatment of invasive Candida spp. infections. Fluconazole is still a major drug for antifungal prophylaxis in the setting of transplantation (solid organ and bone marrow), intensive care unit, and in neutropenic patients. Prophylactic fluconazole still has a place in HIV-positive patients in viro-immunological failure with recurrent mucosal candidiasis. Fluconazole can be used in adult neutropenic patients with systemic candidiasis, as long as the species identified is a priori susceptible. Among non-neutropenic patients with candidaemia fluconazole is one of the first line drugs for susceptible species. Cases reports and uncontrolled studies have also reported its efficacy in the setting of osteoarthritis, endophthalmitis, meningitis, endocarditis and peritonitis caused by Candida spp. among immunocompetent adults. In paediatrics, fluconazole is a well tolerated and major prophylactic drug for high-risk neonates, as well as an alternative treatment for neonatal candidiasis. Importantly 15 years after its introduction in the antifungal armamentarium, fluconazole is still a first line treatment option in several cases of invasive candidiasis. Its prophylactic use should however be limited to selected high-risk patients to limit the risk of emergence of azole-resistant strains.

Efficacy of caspofungin against invasiveCandida or invasiveAspergillus infections in neutropenic patients

BACKGROUND

Neutropenia is an indicator of poor prognosis in patients with fungal infections. All available clinical trial experience from the caspofungin development program was reviewed to ascertain the efficacy of caspofungin in neutropenic patients with documented invasive aspergillosis (IA) or invasive candidiasis (IC).

METHODS

The review was limited to neutropenic patients with proven IC or proven/probable IA at caspofungin onset. Data were available from four clinical trials. All patients had an absolute neutrophil count < 500/mm(3) at the initiation of caspofungin. In all cases caspofungin was administered as monotherapy at a dose of 50 mg/day, after a 70-mg loading dose. In all patients efficacy was assessed at the completion of caspofungin therapy. Success included complete and partial responses.

RESULTS

Sixty-eight neutropenic patients were identified with documented invasive infection, including 27 with IC and 41 with IA. Most patients had acute or chronic leukemia. A favorable response was noted in 63% (17 of 27 patients) of patients with IC, including a 58% (14 of 24 patients) response as first-line therapy and a 100% (3 of 3 patients) response as salvage therapy. Success in candidemia was 68% (17 of 25 patients). Outcomes across the different Candida species were similar. Favorable responses were noted in 39% (16 of 41 patients) of patients with IA, including a 42% (5 of 12 patients) response as first-line therapy and 38% (11 of 29 patients) response as salvage therapy. Success by site of IA was 40% for pulmonary (12 of 30 patients), 43% for sinus (3 of 7 patients), and 25% for skin/disseminated site (1 of 4 patients).

CONCLUSIONS

A review of the caspofungin database demonstrates that this echinocandin is effective in neutropenic patients with documented cases of IC or IA.

Of Yeasts and Hyphae: A Hematologist’s Approach to Antifungal Therapy

Improvements in anticancer treatments, the ability to modify myelosuppression profiles, greater duration and intensity of immunosuppression, and the variety of available antimicrobial therapies have influenced the spectrum of pathogens associated with invasive fungal infection complicating treatment of hematological malignancies and hematopoietic stem cell transplantation. The approaches to the management of these infections encompass strategies of prevention for all those at risk, pre-emptive therapy based upon surrogates of infection before the onset of clinical disease, empirical therapy for patients with clinical evidence of early disease, and directed or targeted therapy for infected patients with established disease. Chemoprophylaxis is effective if applied to the highest risk patients over the duration of the risk. Pre-emptive strategies, while promising, have yet to be validated and linked to reliably predictive nonmicrobiological diagnostic techniques. Empirical antifungal therapy, as it is currently applied, now seems questionable. Patients with probable or proven invasive fungal infection still have suboptimal outcomes despite the availability of promising anti-fungal agents. Strategies examining the concept of dose-intensity and combination regimens require careful study and cannot yet be regarded as an acceptable standard of practice.

Infectious Complications of Cancer Therapy

Advances in the management of cancer, particularly the development of new chemotherapeutic agents, have greatly improved the survival and outcome of patients with hematologic malignancies and solid tumors; overall 5-year survival rates in cancer patients have improved from 39% in the 1960s to 60% in the 1990s.1 However, infection, caused by both the underlying malignancy and cancer chemotherapy, particularly myelosuppressive chemotherapy, remains a persistent challenge.

Successful treatment of fungus balls due to fluconazole-resistant Candida sake obstructing ureter stents in a renal transplant patient

Reported here is the case of a 72-year-old renal transplant recipient with stenosis of the neo-ureter requiring stents, who was admitted to hospital with pyonephrosis caused by fungus balls. Fluconazole-resistant Candida sake was grown. Treatment with external drainage of the renal pelvis and intravenous and local administration of caspofungin resulted in relief of the obstruction. Eradication of the infection was achieved by surgical removal of the ureter with all stents and construction of a cysto-pyelostomy.

Current treatment strategies for disseminated candidiasis

The incidence of disseminated candidiasis has increased dramatically over the past several decades. Fortunately, in recent years, a variety of new antifungal agents have become available to treat these infections. On the basis of efficacy, safety, and cost considerations, fluconazole is the agent of choice for the empirical treatment of disseminated candidiasis in nonneutropenic, hemodynamically stable patients, unless a patient is suspected to be infected with an azole-resistant species (i.e., Candida glabrata or Candida krusei). For hemodynamically unstable or neutropenic patients, agents with broader species coverage, such as polyenes, echinocandins, or, possibly, voriconazole, are preferred for empirical treatment of candidemia. Modification of the initial, empirical regimen depends on the response to therapy and the subsequent identification of the species of the offending pathogen. Echinocandins or high-dose polyenes are preferred for the treatment of infections with C. glabrata or C. krusei. Central venous catheters should be removed from all patients who have disseminated candidiasis, if feasible, and antifungal therapy should be administered to all patients who have candidemia or proven candidiasis.

Pharmacoeconomics of antifungal pharmacotherapy – challenges and future directions

The frequency and severity of invasive fungal infections have been increasingly recognised and new antifungal therapies have expanded the therapeutic armamentarium available to manage such infections. Antifungal agents comprise a significant portion of antibiotic expenditures at major medical centres, prompting adoption of cost-containment measures and treatment guidelines. This paper reviews available data regarding the costs associated with managing fungal infections, including pharmacoeconomic analyses that have been performed in the setting of documented fungal infections, as well as prophylactic and empiric use of antifungal agents. The challenges of performing such studies are discussed, as well as the limitations of published investigations. Finally, recommendations are made regarding the design and implementation of future pharmacoeconomic analyses that can help establish the true costs of managing invasive fungal infections in at-risk patient populations.

International, open-label, noncomparative, clinical trial of micafungin alone and in combination for treatment of newly diagnosed and refractory candidemia

Candida spp. are the fourth leading cause of bloodstream infections, and non-albicans species are increasing in importance. Micafungin is a new echinocandin antifungal agent with excellent in vitro activity against Candida spp. Pediatric, neonatal, and adult patients with new or refractory candidemia were enrolled into this open-label, noncomparative, international study. The initial dose of micafungin was 50 mg/d (1 mg/kg for patients <40 kg) for infections due to C. albicans and 100 mg/d (2 mg/kg for patients <40 kg) for infections due to other species. Dose escalation was allowed. Maximum length of therapy was 42 days. A total of 126 patients were evaluable (received at least five doses of micafungin). Success (complete or partial response) was seen in 83.3% patients overall. Success rates for treatment of infections caused by the most common Candida spp. were as follows: C. albicans 85.1%, C. glabrata 93.8%, C. parapsilosis 86.4%, and C. tropicalis 83.3%. Serious adverse events related to micafungin were uncommon. Micafungin shows promise as a safe and effective agent for the treatment of newly diagnosed and refractory cases of candidemia. Large-scale, randomized, controlled trials are warranted.

Voriconazole versus a regimen of amphotericin B followed by fluconazole for candidaemia in non-neutropenic patients: a randomised non-inferiority trial

BACKGROUND

Voriconazole has proven efficacy against invasive aspergillosis and oesophageal candidiasis. This multicentre, randomised, non-inferiority study compared voriconazole with a regimen of amphotericin B followed by fluconazole for the treatment of candidaemia in non-neutropenic patients.

METHODS

Non-neutropenic patients with a positive blood culture for a species of candida and clinical evidence of infection were enrolled. Patients were randomly assigned, in a 2:1 ratio, either voriconazole (n=283) or amphotericin B followed by fluconazole (n=139). The primary efficacy analysis was based on clinical and mycological response 12 weeks after the end of treatment, assessed by an independent data-review committee unaware of treatment assignment.

FINDINGS

Of 422 patients randomised, 370 were included in the modified intention-to-treat population. Voriconazole was non-inferior to amphotericin B/fluconazole in the primary efficacy analysis, with successful outcomes in 41% of patients in both treatment groups (95% CI for difference -10.6% to 10.6%). At the last evaluable assessment, outcome was successful in 162 (65%) patients assigned voriconazole and 87 (71%) assigned amphotericin B/fluconazole (p=0.25). Voriconazole cleared blood cultures as quickly as amphotericin B/fluconazole (median time to negative blood culture, 2.0 days). Treatment discontinuations due to all-cause adverse events were more frequent in the voriconazole group, although most discontinuations were due to non-drug-related events and there were significantly fewer serious adverse events and cases of renal toxicity than in the amphotericin B/fluconazole group.

INTERPRETATION

Voriconazole was as effective as the regimen of amphotericin B followed by fluconazole in the treatment of candidaemia in non-neutropenic patients, and with fewer toxic effects.

RELEVANCE TO PRACTICE

There are several options for treatment of candidaemia in non-neutropenic patients, including amphotericin B, fluconazole, voriconazole, and echinocandins. Voriconazole can be given both as initial intravenous treatment and as an oral stepdown agent.

A retrospective Evaluation of fluconazole for the treatment of Candida glabrata fungemia

BACKGROUND

Candida glabrata accounts for 21% of Candida bloodstream isolates in the United States and ranges from susceptible-dose-dependent to resistant to fluconazole. A fluconazole dose of 800 mg/d ( approximately 12 mg/kg per day) is predicted to produce peak plasma concentrations that surpass the susceptible-dose-dependent MIC breakpoint of 16 to 32 mug/mL. Accordingly, the Infectious Diseases Society of America treatment guidelines for candidiasis recommend fluconazole 12 mg/kg per day as an alternative option for treatment of C glabrata fungemia.

OBJECTIVE

The main objective of this study was to evaluate fluconazole retrospectively as a treatment for C glabrata fungemia.

METHODS

Data were collected through a database that stores patient information electronically and can be accessed and queried, and chart review at Barnes-Jewish Hospital (St. Louis, Missouri) from January 1999 to August 2002. Eligible patients who had at least 1 positive blood culture for C glabrata and received at least 1 dose of fluconazole were identified through the electronic query. Chart reviews of these patients followed. The primary outcomes were fungemia eradication and in-hospital mortality.

RESULTS

Of the total 124 cases of C glabrata fungemia identified, 54 patient charts were evaluable. Chart review revealed that 65% (17/26) of patients receiving fluconazole as the sole antifungal therapy had successful bloodstream eradication of C glabrata, whereas approximately 54% (15/28) of patients who were changed from fluconazole to an amphotericin B formulation had successful bloodstream eradication. Although no association was found between fluconazole dose and fungemia eradication in the entire study population, higher doses of fluconazole (> or =400 mg/d) were more likely to achieve fungemia eradication than lower doses (< or =400 mg/d) in the subset of patients who received only fluconazole (P = 0.042). Mortality rates were approximately 24% (4/17) and 40% (6/15) in patients having successful bloodstream eradication with fluconazole alone and with fluconazole followed by amphotericin B, respectively, compared with 38% (3/8) in patients with persistent fungemia who received fluconazole alone.

CONCLUSIONS

Fluconazole was a viable therapy for C glabrata fungemia, with bloodstream eradication in 65% of patients and mortality rates of 24% to 40% in this retrospective chart review.

Adverse effects of antifungal therapies in invasive fungal infections: review and meta-analysis

Amphotericin B is the main therapeutic agent for the treatment of invasive fungal infections; however, it is associated with significant toxicities that limit its use. Other systemic antifungal agents have been developed to improve tolerability while maintaining the efficacy profile of conventional amphotericin B. Fifty-four studies involving 9,228 patients were assessed for the frequency of adverse effects of the main systemic antifungal agents. While the results suggest that liposomal amphotericin B (L-AmB) is the least nephrotoxic of the lipid formulations (14.6%), that conventional amphotericin B (AmB) is the most nephrotoxic (33.2%), and that itraconazole is the most hepatotoxic (31.5%), the lack of standard definitions of antifungal-related adverse effects limits the validity of these results. Furthermore, heterogeneous patient pools and differing protocols make it difficult to draw direct comparisons between studies. With the advent of newer classes of systemic antifungal agents, future trials should conform to definitions that are universally applicable and clinically relevant to allow for such comparisons and to enable evidence-based decision-making.

Overview of transplant mycology

PURPOSE

The epidemiology, clinical manifestation, diagnosis, and management of invasive mycoses in transplant patients are described.

SUMMARY

The incidence of and mortality from invasive mycoses have increased in transplant patients. Candida and Aspergillus are the two most common fungal pathogens in this patient population. The use of immunosuppressive and myeloablative therapies and other factors increases the risk of invasive mycoses. A high index of suspicion and clinical clues are needed for the diagnosis of Candida and Aspergillus infections because reliable diagnostic techniques are not available and the patient presentation is nonspecific. Targeted prophylaxis for patients at high risk for morbidity and mortality and early, aggressive treatment using broad-spectrum antifungal agents are recommended. Prophylaxis using itraconazole reduces the risk of treatment failure due to resistant pathogens compared with fluconazole. Voriconazole might prove advantageous compared with fluconazole and itraconazole for prophylaxis because of its extended spectrum and predictable blood levels. Caspofungin seems as effective as and less toxic than amphotericin B for this use. Voriconazole is more effective than amphotericin B for the treatment of aspergillosis. Caspofungin is comparable to voriconazole in efficacy as salvage treatment after failure to respond to other antifungal agents.

CONCLUSION

Caspofungin plus voriconazole and other combination therapies often are used for the treatment of aspergillosis yet data to support such use are yet to be produced. The investigational agents posaconazole, micafungin, and anidulafungin appear promising as salvage treatment of various invasive mycoses.

Antimicrobial therapy for patients with severe sepsis and septic shock: an evidence-based review

OBJECTIVE

In 2003, critical care and infectious disease experts representing 11 international organizations developed management guidelines for antimicrobial therapy for patients with severe sepsis and septic shock that would be of practical use for the bedside clinician, under the auspices of the Surviving Sepsis Campaign, an international effort to increase awareness and improve outcome in severe sepsis.

DESIGN

The process included a modified Delphi method, a consensus conference, several subsequent smaller meetings of subgroups and key individuals, teleconferences, and electronic-based discussion among subgroups and among the entire committee.

METHODS

The modified Delphi methodology used for grading recommendations built on a 2001 publication sponsored by the International Sepsis Forum. We undertook a systematic review of the literature graded along five levels to create recommendation grades from A to E, with A being the highest grade. Pediatric considerations to contrast adult and pediatric management are in the article by Parker et al. on p. S591.

CONCLUSION

Since the prompt institution of therapy that is active against the causative pathogen is one of the most important predictors of outcome, clinicians must establish a system for rapid administration of a rationally chosen drug or combination of drugs when sepsis or septic shock is suspected. The expanding number of antibacterial, antifungal, and antiviral agents available provides opportunities for effective empiric and specific therapy. However, to minimize the promotion of antimicrobial resistance and cost and to maximize efficacy, detailed knowledge of the likely pathogens and the properties of the available drugs is necessary for the intensivist.

Sepsis associated with immunosuppressive medications: an evidence-based review

OBJECTIVE

In 2003, critical care and infectious disease experts representing 11 international organizations developed management guidelines for sepsis associated with immunosuppressive medications that would be of practical use for the bedside clinician, under the auspices of the Surviving Sepsis Campaign, an international effort to increase awareness and improve outcome in severe sepsis.

DESIGN

The process included a modified Delphi method, a consensus conference, several subsequent smaller meetings of subgroups and key individuals, teleconferences, and electronic-based discussion among subgroups and among the entire committee.

METHODS

The modified Delphi methodology used for grading recommendations built on a 2001 publication sponsored by the International Sepsis Forum. We undertook a systematic review of the literature graded along five levels to create recommendation grades from A to E, with A being the highest grade. Pediatric considerations to contrast adult and pediatric management are in the article by Parker et al. on p. S591.

CONCLUSION

Immunosuppressed patients, by definition, are susceptible to a wider spectrum of infectious agents than immunologically normal patients and, thus, require a broader spectrum antimicrobial regimen when they present with sepsis or septic shock. Special expertise managing immunosuppressed patient populations is needed to predict and establish the correct diagnosis and to choose appropriate empiric and specific agents and maximize the likelihood that patients will survive these microbial challenges.

A new era of antifungal therapy

Invasive fungal infections pose major management problems for clinicians caring for hematopoietic cell transplant patients. Two major fungal genera, Candida and Aspergillus, account for most fungal infections. Rates of systemic Candida infection range from 15% to 25%, mostly in the pre-engraftment period. Prophylaxis by fluconazole has dramatically reduced the frequency of early Candida infections. Caspofungin has recently been shown to offer an excellent alternative to amphotericin B (with less toxicity) or fluconazole (with a broader spectrum) for therapy of systemic Candida infections. Aspergillus infections occur in 15% to 20% of allogeneic hematopoietic cell transplant patients, most frequently in the post-engraftment period; they are associated with a severe diminution of cell-mediated immune responses by graft-versus-host disease and prolonged corticosteroid use. Voriconazole, a recently introduced broad-spectrum azole, has excellent activity against Aspergillus and is generally well tolerated. Voriconazole currently offers the best prospect for success and tolerance as a first-line treatment for aspergillosis. Second-line therapies include lipid formulations of amphotericin B, caspofungin, or intravenous itraconazole. Unfortunately, early initiation of therapy for aspergillosis is frequently not possible because of inaccurate diagnostics. One new diagnostic, the galactomannan assay, has recently been approved, and others are in development; these offer promise for earlier diagnosis without the need for invasive procedures. It is hoped that these new therapies and new diagnostics will usher in a new era of antifungal therapy.

High-dose fluconazole therapy for cancer patients with solid tumors and candidemia: an observational, noncomparative retrospective study

BACKGROUND

Response rates for candidemia treated with standard-dose fluconazole (400 mg/day) are approximately 70%. Higher doses of fluconazole have been recommended for susceptible dose-dependent Candida isolates. Herein, we describe the outcome of 20 patients with solid tumors and candidemia treated with high-dose fluconazole (HDF) at The University of Texas M.D. Anderson Cancer Center (1998-2002).

PATIENTS AND METHODS

Patients were identified either by searching the microbiology laboratory database or through direct referral from primary oncology services to the Infectious Diseases Consultative Services. A retrospective review of cases was performed. HDF was defined as > or =600 mg/day.

RESULTS

Five patients were treated with 600 mg/day, whereas 15 patients received 800 mg/day. Only one patient was neutropenic. The median APACHE II score at the onset of candidemia was 12 (range 6-24). The most common species identified were Candida albicans (eight patients, 40%) and Candida parapsilosis (seven patients, 35%). Of 19 patients whose quantitative data were available, eight (42%) had high-grade candidemia [> or =200 colony forming units (CFU)/ml]. Fifteen (83%) of 18 isolates were fluconazole susceptible, and two (both Candida glabrata) were fluconazole resistant (MIC 64 each) in vitro. Nineteen patients (95%) responded to HDF therapy. The only HDF failure occurred in a patient with C. glabrata (MIC 64.0) infection. The other patient with C. glabrata (MIC 64.0) infection responded to HDF. Central venous catheters were removed from all patients with > or =10 CFU/ml candidemias. All patients with high-grade candidemias responded to HDF. The median duration of HDF therapy was 16 (range 6-42) days. No significant toxicity occurred.

CONCLUSIONS

Although our data are limited, HDF appears to be well tolerated and may be associated with higher response rates than standard-dose fluconazole in a selected group of patients with solid tumors and candidemia caused by species that are susceptible to this triazole.

Indicaciones del tratamiento antifúngico en pacientes ingresados en servicios de medicina intensiva*

INTRODUCTION

This study investigates the indications for antifungal treatment in patients admitted to intensive care units (ICUs) in Spain and determines the frequency at which each individual drug is prescribed.

METHODS

Observational, multicenter study including all patients admitted to 64 ICUs on 23 March, 22 June, and 16 November, 1999. The use of antifungal agents and the criteria for indicating antifungal therapy were assessed. Patients were classified as colonized or infected by fungi.

RESULTS

In 180 (11.5%) of the 1562 patients included in the study, 219 courses of treatment with antifungal agents were prescribed (antifungal therapy rate of 14 per 100 patients). Fluconazole was the antifungal agent most frequently used, both in infected and colonized patients. The most common reasons for prescribing antifungal therapy were as follows: candiduria (21.9%), severe sepsis with no response to antibiotic therapy (19.6%), and evidence of fungi in two or more non-invasive sites (16.9%). Candidemia was the reason for antifungal treatment in 17 (7.9%) cases. Proven fungal infections accounted for 21.1% of indications. Variables significantly associated with the use of antifungal agents included underlying disease, severity of illness according to the APACHE II score, chronic liver disease, solid tumor, immunosuppression, and organ transplantation. Significant extrinsic risk factors for antifungal therapy included treatment with corticoids, chemotherapy, mechanical ventilation, urgent and/or elective surgery, and previous use of antibiotics.

CONCLUSIONS

A total of 11.5% of patients included in the study were given one or more treatment courses with antifungal agents. Antifungal treatment was prescribed in proved fungal infections in only 21.1% of cases. Fluconazole was the antifungal agent most frequently used.

Clinical impact of the fungicidal activity of caspofungin administered alone or in combination in critically ill patients with severe abdominal candidiasis refractory to conventional antifungal drugs: case studies and critical review of the problem

We discuss two cases of abdominal candidiasis in critically ill patients with multiple organ failure and sepsis. Microbiological and clinical courses remained unresponsive to apparently appropriate antifungal therapy with azole or polyene derivatives. Both microbiological and clinical outcomes dramatically improved after starting caspofungin therapy. Lack of cross-resistance, lack of toxicity and potent fungicidal activity make caspofungin a very attractive drug in life threatening abdominal candidiasis. The optimal treatment of life threatening candidiasis remains a controversial issue. Because of recent advances in the field, we propose a critical review of the problem of refractory candidiasis.

Management of candidiasis Management of Candida species infections in critically ill patients

Invasive candidiasis is a feared infection with mortality similar to that of septic shock (40-60%). Improved knowledge of its pathophysiology and the availability of new compounds for antifungal therapy and prophylaxis have contributed to improving the prognosis of severe candidal infections among immunosuppressed patients at the possible cost of the emergence of non-albicans strains of candida with lower susceptibility to azoles. This review focuses on the management of invasive deep-seated candidiasis in critically ill, non-immunocompromised patients. We discuss antifungal use, indications, potential benefit, and main secondary effects. Prevention strategies include pre-emptive antifungal therapy and azole-based prophylaxis. For patients at lower initial risk, pre-emptive therapy should be based on a management strategy that takes into account the presence of definite risk factors and the dynamics of candida colonisation. Among critically ill patients, azole prophylaxis is effective and is not associated with acquisition of resistance; it must be restricted to highly selected groups of patients at high risk only.

Epidemiology of Candida species infections in critically ill non-immunosuppressed patients

A substantial proportion of patients become colonised with Candida spp during hospital stay, but only few subsequently develop severe infection. Clinical signs of severe infection manifest early but lack specificity until late in the course of the disease, thus representing a particular challenge for diagnosis. Mostly nosocomial, invasive candidiasis occurs in only 1-8% of patients admitted to hospitals, but in around 10% of patients housed in intensive care units where it can represent up to 15% of all nosocomial infections. We review the epidemiology of invasive candidiasis in non-immunocompromised, critically ill patients with special emphasis on disease trends over time, pathophysiology, diagnostic approach, risk factors, and impact. Recent epidemiological data suggesting that the emergence of non-albicans candida strains with reduced susceptibility to azoles, previously linked to the use of new antifungals for empiric and prophylactic therapy in immunocompromised patients, may not have occurred in the critically ill. Management of invasive candidiasis in these patients will be addressed in the December issue of The Lancet Infectious Diseases.

Echinocandin antifungal drugs

The echinocandins are large lipopeptide molecules that are inhibitors of beta-(1,3)-glucan synthesis, an action that damages fungal cell walls. In vitro and in vivo, the echinocandins are rapidly fungicidal against most Candida spp and fungistatic against Aspergillus spp. They are not active at clinically relevant concentrations against Zygomycetes, Cryptococcus neoformans, or Fusarium spp. No drug target is present in mammalian cells. The first of the class to be licensed was caspofungin, for refractory invasive aspergillosis (about 40% response rate) and the second was micafungin. Adverse events are generally mild, including (for caspofungin) local phlebitis, fever, abnormal liver function tests, and mild haemolysis. Poor absorption after oral administration limits use to the intravenous route. Dosing is once daily and drug interactions are few. The echinocandins are widely distributed in the body, and are metabolised by the liver. Results of studies of caspofungin in candidaemia and invasive candidiasis suggest equivalent efficacy to amphotericin B, with substantially fewer toxic effects. Absence of antagonism in combination with other antifungal drugs suggests that combination antifungal therapy could become a general feature of the echinocandins, particularly for invasive aspergillosis.

A prospective observational study of candidemia: epidemiology, therapy, and influences on mortality in hospitalized adult and pediatric patients

We conducted a prospective, multicenter observational study of adults (n=1447) and children (n=144) with candidemia at tertiary care centers in the United States in parallel with a candidemia treatment trial that included nonneutropenic adults. Candida albicans was the most common bloodstream isolate recovered from adults and children (45% vs. 49%) and was associated with high mortality (47% among adults vs. 29% among children). Three-month survival was better among children than among adults (76% vs. 54%; P<.001). Most children received amphotericin B as initial therapy, whereas most adults received fluconazole. In adults, Candida parapsilosis fungemia was associated with lower mortality than was non-parapsilosis candidemia (24% vs. 46%; P<.001). Mortality was similar among subjects with Candida glabrata or non-glabrata candidemia; mortality was also similar among subjects with C. glabrata candidemia who received fluconazole rather than other antifungal therapy. Subjects in the observational cohort had higher Acute Physiology and Chronic Health Evaluation II scores than did participants in the clinical trial (18.6 vs. 16.1), which suggests that the former subjects are more often excluded from therapeutic trials.

A randomized and blinded multicenter trial of high-dose fluconazole plus placebo versus fluconazole plus amphotericin B as therapy for candidemia and its consequences in nonneutropenic subjects

A randomized, blinded, multicenter trial was conducted to compare fluconazole (800 mg per day) plus placebo with fluconazole plus amphotericin B (AmB) deoxycholate (0.7 mg/kg per day, with the placebo/AmB component given only for the first 5-6 days) as therapy for candidemia due to species other than Candida krusei in adults without neutropenia. A total of 219 patients met criteria for a modified intent-to-treat analysis. The groups were similar except that those who were treated with fluconazole plus placebo had a higher mean (+/- standard error) Acute Physiology and Chronic Health Evaluation II score (16.8+/-0.6 vs. 15.0+/-0.7; P=.039). Success rates on study day 30 by Kaplan-Meier time-to-failure analysis were 57% for fluconazole plus placebo and 69% for fluconazole plus AmB (P=.08). Overall success rates were 56% (60 of 107 patients) and 69% (77 of 112 patients; P=.043), respectively; the bloodstream infection failed to clear in 17% and 6% of subjects, respectively (P=.02). In nonneutropenic subjects, the combination of fluconazole plus AmB was not antagonistic compared with fluconazole alone, and the combination trended toward improved success and more-rapid clearance from the bloodstream.

Species distribution and antifungal susceptibility profile of Candida spp. bloodstream isolates from Latin American hospitals

From March 1999 to March 2000, we conducted a prospective multicenter study of candidemia involving five tertiary care hospitals from four countries in Latin America. Yeast isolates were identified by classical methods and the antifungal susceptibility profile was determined according to the National Committee for Clinical Laboratory Standards microbroth assay method. During a 12 month-period we were able to collect a total of 103 bloodstream isolates of Candida spp. C. albicans was the most frequently isolated species accounting for 42% of all isolates. Non-albicans Candida species strains accounted for 58% of all episodes of candidemia and were mostly represented by C. tropicalis (24.2%) and C. parapsilosis (21.3%). It is noteworthy that we were able to identify two cases of C. lusitaniae from different institutions. In our casuistic, non-albicans Candida species isolates related to candidemic episodes were susceptible to fluconazole. Continuously surveillance programs are needed in order to identify possible changes in the species distribution and antifungal susceptibility patterns of yeasts that may occurs after increasing the use of azoles in Latin American hospitals.

Systemic mycoses in the immunocompromised host: an update in antifungal therapy

Despite significant advances in the management of immunosuppressed patients, invasive fungal infections remain an important life-threatening complication. In the last decade several new antifungal agents, including compounds in pre-existing classes (new generation of triazoles, polyenes in lipid formulations) and novel classes of antifungals with a unique mechanism of action (echinocandins), have been introduced in clinical practice. Ongoing and future studies will determine their exact role in the management of different mycoses. The acceleration of antifungal drug discovery offers promise for the management of these difficult to treat opportunistic infections.

British Society for Medical Mycology proposed standards of care for patients with invasive fungal infections

Outcomes for invasive fungal infections have greatly improved in the past decade, and several new antifungal drugs have been or will be licensed in the next few years. Early accurate diagnosis and appropriate treatment have major impact on survival. In a 1995 survey of laboratory practice in the UK for mycology, major disparities were seen, with many laboratories not undertaking even simple diagnostic procedures. Delays in processing and inadequate procedures for handling samples, incomplete or delayed reporting of results, or a combination of these, compromise the care of patients. In randomised trials of antifungal chemotherapy, optimum treatments and good alternatives for others have been defined for some infections. High-quality care requires a multidisciplinary approach to diagnosis and management. In this review, we propose microbiology, histopathology, radiology, and clinical auditing standards, with the evidence base for each reviewed. The standards are absolutes, and, therefore, provide a straightforward basis for improving services to patients if they are all implemented.

Clinical pharmacology of antifungal compounds

Prompted by the worldwide surge in fungal infections, the past decade has witnessed a considerable expansion in antifungal drug research. New compounds have entered the clinical arena, and major progress has been made in defining paradigms of antifungal therapies. This article provides an up-to-date review on the clinical pharmacology, indications, and dosage recommendations of approved and currently investigational therapeutics for treatment of invasive fungal infections in adult and pediatric patients.

[Treatment approach for fungal infections in critically ill patients admitted to intensive care units: results of a multicenter survey]

INTRODUCTION

Two consensus conferences taking place in the United States and Spain were organized to optimize diagnosis and treatment of Candida spp. infections. Among other results, clinical scenarios in which early prescription of antifungal agents is indicated were identified.

OBJECTIVE

To determine the criteria followed by physicians for prescribing antifungal agents in critically ill patients in our country and to investigate adherence to the guidelines proposed by the consensus conferences.

METHODS

A questionnaire was designed and directed to 4th- and 5th-year residents in intensive care medicine and to specialists in intensive care with training in infectious diseases or other medical areas. Four case reports for which expert consensus indicates early antifungal treatment were included in the questionnaire; 1) recurrent peritonitis secondary to perforation of the digestive tract, with mixed flora including fungi; 2) persistent febrile syndrome in a patient with multiple mucosal fungal colonizations treated with broad-spectrum antibiotics; 3) candiduria and pyuria in a febrile patient; and 4) candidemia.

RESULTS

A total of 135 questionnaires from 45 different ICUs were returned (60% response rate). In the candidemia and fungal peritonitis examples, early treatment with antifungal agents was indicated in 100% and 85.9% of responses, respectively, whereas for sepsis with multifocal candidiasis and candiduria associated with pyuria and fever, early treatment was prescribed in only 41.5% and 55.6% of responses, respectively. There were no significant differences in response with regard to degree of training of the physicians surveyed. Fluconazole prescription predominated, mainly at doses of 400 mg/day, in mixed peritonitis, disseminated candidiasis and candiduria, whereas amphotericin B lipid formulations were preferentially indicated in cases of candidemia. Antifungal treatment (early or late) was prescribed in all responses for candidemia, in 95.5% for mixed peritonitis (fungi and bacteria), in 79.5% for multifocal candidiasis in patients with persistent sepsis, and in 77.9% for candiduria with fever and pyuria.

CONCLUSIONS

Adherence to recommendations from the consensus conferences was high among intensive medicine specialists, with no differences according to level of training in infectious diseases.

Comparison of caspofungin and amphotericin B for invasive candidiasis

BACKGROUND

Caspofungin is an echinocandin agent with fungicidal activity against candida species. We performed a double-blind trial to compare caspofungin with amphotericin B deoxycholate for the primary treatment of invasive candidiasis.

METHODS

We enrolled patients who had clinical evidence of infection and a positive culture for candida species from blood or another site. Patients were stratified according to the severity of disease, as indicated by the Acute Physiology and Chronic Health Evaluation (APACHE II) score, and the presence or absence of neutropenia and were randomly assigned to receive either caspofungin or amphotericin B. The study was designed to compare the efficacy of caspofungin with that of amphotericin B in patients with invasive candidiasis and in a subgroup with candidemia.

RESULTS

Of the 239 patients enrolled, 224 were included in the modified intention-to-treat analysis. Base-line characteristics, including the percentage of patients with neutropenia and the mean APACHE II score, were similar in the two treatment groups. A modified intention-to-treat analysis showed that the efficacy of caspofungin was similar to that of amphotericin B, with successful outcomes in 73.4 percent of the patients treated with caspofungin and in 61.7 percent of those treated with amphotericin B (difference after adjustment for APACHE II score and neutropenic status, 12.7 percentage points; 95.6 percent confidence interval, -0.7 to 26.0). An analysis of patients who met prespecified criteria for evaluation showed that caspofungin was superior, with a favorable response in 80.7 percent of patients, as compared with 64.9 percent of those who received amphotericin B (difference, 15.4 percentage points; 95.6 percent confidence interval, 1.1 to 29.7). Caspofungin was as effective as amphotericin B in patients who had candidemia, with a favorable response in 71.7 percent and 62.8 percent of patients, respectively (difference, 10.0 percentage points; 95.0 percent confidence interval, -4.5 to 24.5). There were significantly fewer drug-related adverse events in the caspofungin group than in the amphotericin B group.

CONCLUSIONS

Caspofungin is at least as effective as amphotericin B for the treatment of invasive candidiasis and, more specifically, candidemia.

The Pathophysiology and Treatment of Candida Sepsis

Sepsis can occur during disseminated candidiasis, but its pathogenesis differs from that caused by typical prokaryotic pathogens. Complex interactions between defects in host defense and "relative" virulence factors expressed by Candida lead to dissemination of the saprophyte to parenchymal organs, and subsequently to onset of multiorgan failure. This review focuses first on the pathophysiology of Candida sepsis, detailing current understanding of host-pathogen interactions. We then consider the choice of antifungal and supportive treatments.

Pharmacotherapy of Candida bloodstream infections: new treatment options, new era

Evolving medical practices and the widespread use of fluconazole have clearly affected the spectrum of invasive mycoses now encountered by clinicians. The proportion of infections due to azole-resistant Candida species and invasive moulds has increased steadily over the last decade, creating a need for broad-spectrum antifungal agents with safety profiles similar to fluconazole. Efforts to address this need have lead to the reformulation of older, broad-spectrum antifungals and the development of new agents with enhanced activity against non-C. albicans and Aspergillus species. This review highlights pharmacodynamic, pharmacokinetic, safety and cost considerations for current and emerging antifungal therapies to be used in the treatment of bloodstream candidiasis.

Infections in the neutropenic patient--new views of an old problem

Infection in the neutropenic patient has remained a major clinical challenge for over three decades. While diagnostic and therapeutic interventions have improved greatly during this period, increases in the number of patients with neutropenia, changes in the etiologic agents involved, and growing antibiotic resistance have continued to be problematic. The evolving etiology of infections in this patient population is reviewed by Dr. Donowitz. Presently accepted antibiotic regimens and practices are discussed, along with ongoing controversies. In Section II, Drs. Maki and Crnich discuss line-related infection, which is a major infectious source in the neutropenic. Defining true line-related bloodstream infection remains a challenge despite the fact that various methods to do so exist. Means of prevention of line related infection, diagnosis, and therapy are reviewed. Fungal infection continues to perplex the infectious disease clinician and hematologist/oncologist. Diagnosis is difficult, and many fungal infections will lead to increased mortality even with rapid diagnosis and therapy. In Section III, Dr. Pappas reviews the major fungal etiologies of infection in the neutropenic patient and the new anti-fungals that are available to treat them. Finally, Dr. Rolston reviews the possibility of outpatient management of neutropenic fever. Recognizing that neutropenics represent a heterogeneous group of patients, identification of who can be treated as an outpatient and with what antibiotics are discussed.

Management of Candidiasis in Critically Ill Patients

Fungal infections have been increasing at an alarming rate in critically ill patients. Candida is now the fourth most common pathogen isolated from the bloodstream and is associated with significant morbidity, mortality, and economic consequences. Novel antifungals have been developed in recent years to provide alternatives to amphotericin B, which continues to be the standard therapy for most invasive fungal infections. These alternatives include lipid-based amphotericin B, ketoconazole, fluconazole, itraconazole, caspofungin, and potentially voriconazole. Optimal therapy for the various forms of candidiasis remains controversial. A standardized antifungal susceptibility testing method for Candida isolates has been developed to assist drug selection, but its clinical relevance remains to be determined. The relative susceptibility of Candida isolates can be estimated by the species. Specifically, C krusei is resistant to azoles, C glabrata may be resistant to azoles, and C lusitaniae may be resistant to amphotericin B Candida infections can affect any organ system, and the diagnosis of such infections remains difficult. The Infectious Diseases Society of America recently developed guidelines for the management of candidiasis. This review includes a brief discussion of systemically administered antifungal agents and provides a synopsis of the practice guidelines for the management of candidiasis.

Changing spectrum of invasive candidiasis and its therapeutic implications

Emerging trends in invasive candidiasis are notable for a dramatic increase in infections due to non-albicans Candida species. An increasing number of immunocompromised patients at risk from fungal infections, an overall greater acuity of illness in the hospitalized patients, particularly those in the critical care units, escalating rates of broad-spectrum antibiotic usage, and wide utilization of azoles as prophylaxis have probably contributed towards the changing epidemiology of invasive candidiasis. Given the inherent decreased susceptibility of many of the non-albicans Candida species to currently available antifungal agents, these evolving trends have far-reaching clinical relevance.

Fluconazole vs. amphotericin B for the management of candidaemia in adults: a meta-analysis

The incidence of bloodstream infections caused by Candida species is rising. Few published studies have compared the efficacy of fluconazole with that of amphotericin B. We performed a meta-analysis of the prospective studies that compared fluconazole and amphotericin B for the treatment of candidaemia in adults. Data on total mortality, candidaemia-attributable mortality, efficacy, microbiological failure, and toxicity were extracted from eligible studies. All studies appeared homogeneous with respect to the outcome measures. Most patients were at relatively low risk for death as evidenced by the low average physiologic score and the lack of intense immunosuppression. The odds ratios (OR) of treatment with amphotericin B versus fluconazole and 95% confidence intervals (CI) were as follows: total mortality (OR, 1.06; CI, 0.89-1.25), candidaemia-attributable mortality (OR, 1.0; CI, 0.70-1.45), clinical response (OR, 1.14; CI, 0.93-1.39) and microbiological failure according to all Candida species (OR, 0.99; CI, 0.78-1.26). A trend favouring amphotericin B was seen in mycological eradication of non-albicans Candida species (OR, 0.70; CI, 0.47-1.06). Finally, amphotericin B was more toxic than fluconazole (OR, 2.94; CI, 2.14-4.4). In conclusion, fluconazole is as efficacious and less toxic than amphotericin B in stable, not severely immunosuppressed candidaemic patients at low risk for death. However, fluconazole may be less effective than amphotericin B in candidaemias caused by some non-albicans Candida species.

A clinical perspective for the management of invasive fungal infections: focus on IDSA guidelines. Infectious Diseases Society of America

Invasive fungal infections, especially candidiasis and aspergillosis, are a major cause of morbidity and mortality. Many controversies surround the management of these infections. A critical overview of the recent Infectious Diseases Society of America practice guidelines is provided, as are comments on both the conundrums and future perspectives in medical mycology.

Antifungal susceptibility testing of fluconazole by flow cytometry correlates with clinical outcome

Susceptibility testing of fungi by flow cytometry (also called fluorescence-activated cell sorting [FACS]) using vital staining with FUN-1 showed a good correlation with the standard M27-A procedure for assessing MICs. In this study we determined MICs for blood culture isolates from patients with candidemia by NCCLS M27-A and FACS methods and correlated the clinical outcome of these patients with in vitro antifungal resistance test results. A total of 24 patients with candidemia for whom one or more blood cultures were positive for a Candida sp. were included. Susceptibility testing was performed by NCCLS M27-A and FACS methods. The correlation of MICs (NCCLS M27-A and FACS) and clinical outcome was calculated. In 83% of the cases, the MICs of fluconazole determined by FACS were within 1 dilution of the MICs determined by the NCCLS M27-A method. For proposed susceptibility breakpoints, there was 100% agreement between the M27-A and FACS methods. In the FACS assay, a fluconazole MIC of <1 microg/ml was associated with cure (P < 0.001) whereas an MIC of > or =1 microg/ml was associated with death (P < 0.001). The M27-A-derived fluconazole MICs did not correlate with outcome (P = 1 and P = 0.133).

Need for alternative trial designs and evaluation strategies for therapeutic studies of invasive mycoses

Studies of invasive fungal infections have been and remain difficult to implement. Randomized clinical trials of fungal infections are especially slow and expensive to perform because it is difficult to identify eligible patients in a timely fashion, to prove the presence of the fungal infection in an unequivocal fashion, and to evaluate outcome in a convincing fashion. Because of these challenges, licensing decisions for antifungal agents have to date depended heavily on historical control comparisons and secondary advantages of the new agent. Although the availability of newer and potentially more effective agents makes these approaches less desirable, the fundamental difficulties of trials of invasive fungal infections have not changed. Therefore, there is a need for alternative trial designs and evaluation strategies for therapeutic studies of invasive mycoses, and this article summarizes the possible strategies in this area.

Impact of an intravenous fluconazole restriction policy on patient outcomes

OBJECTIVE

To evaluate both the economic and clinical impact of an intravenous fluconazole restriction policy in a university teaching hospital.

METHODS

Intravenous fluconazole was restricted to patients unable to take oral medications due to significant nausea or to patients whose oral intake was restricted. A retrospective chart review and computerized record review was conducted in patients receiving intravenous or oral fluconazole from January 1 to June 30, 1997, and again from January 1 to June 30, 1998, after implementation of the policy.

RESULTS

Six-month institutional expenditures for intravenous fluconazole decreased following policy implementation, from $81,900 to $45,400, an estimated annual institutional savings of $73,000. A 47% reduction in the number of patients treated with intravenous fluconazole was observed over the six-month period after policy implementation. During this time, the rate of successful clinical outcomes for documented or suspected disseminated Candida albicans infection or febrile neutropenia remained the same (66.6% prepolicy and 65.9% postpolicy; p = 0.95). Similarly, the number of deaths in patients receiving fluconazole remained unchanged (p = 0.31).

CONCLUSIONS

A restriction policy for intravenous fluconazole results in significant cost savings, with no significant decrease in successful outcomes or change in mortality.

Rapid identification of medically important Candida to species level by polymerase chain reaction and single-strand conformational polymorphism

Invasive fungal disease has taken a great toll on immunocompromised patients. With the emergence of fluconazole and amphotericin B resistance, the rapid identification of fungi to species level is of clinical relevance in guiding appropriate antifungal therapy. Among these opportunistic fungi, Candida species are the most commonly encountered. We had developed a molecular method utilizing single-strand conformational polymorphism (SSCP) to delineate different patterns on a 260-bp amplicon from the 28S rRNA gene from six medically important Candida species. The SSCP banding patterns obtained from a total of 52 isolates were sufficiently unique to allow distinction between the species, thus indicated a high level of specificity. This method of PCR-SSCP can provide a simple and specific method for the rapid identification of medically important Candida to species level.

Management of Infections Caused by Candida glabrata

Candida glabrata infections undoubtedly have become more frequent, and are now common. They appear to be the consequence of widespread and often indiscriminate use of azoles, especially fluconazole. This species constitutes the Achilles heel of all available azoles, including newer ones in the pipeline. Even when amphotericin B is used, higher dosages are now required. Little is known about the epidemiology of and risk factors for this troublesome species; even less about its virulence factors. However, studying the resistance mechanisms of this haploid organism may provide answers in developing new fungicidal agents.

New drugs and novel targets for treatment of invasive fungal infections in patients with cancer

Invasive fungal infections have emerged as important causes of morbidity and mortality in profoundly immunocompromised patients with cancer. Current treatment strategies for these infections are limited by antifungal resistance, toxicity, drug interactions, and expense. In order to overcome these limitations, new antifungal compounds are being developed, which may improve our therapeutic armamentarium for prevention and treatment of invasive mycoses in high-risk patients with neoplastic diseases.