Posaconazole vs. fluconazole or itraconazole prophylaxis in patients with neutropenia

Recommendations for the treatment of established fungal infections

Evidence-based guidelines for the treatment of established fungal infections in the adult haematology/oncology setting were developed by a national consensus working group representing clinicians, pharmacists and microbiologists. These updated guidelines replace the previous guidelines published in the Internal Medicine Journal by Slavin et al. in 2004. The guidelines are pathogen-specific and cover the treatment of the most common fungal infections including candidiasis, aspergillosis, cryptococcosis, zygomycosis, fusariosis, scedosporiosis, and dermatophytosis. Recommendations are provided for management of refractory disease or salvage therapies, and special sites of infections such as the cerebral nervous system and the eye. Because of the widespread use newer broad-spectrum triazoles in prophylaxis and empiric therapy, these guidelines should be implemented in concert with the updated prophylaxis and empiric therapy guidelines published by this group.

Infectious complications of acute and chronic GVHD

Immune defects prolonged by treatment regimens for graft-versus-host disease (GVHD) include cell-mediated immunity and hypogammaglobulinemia. Infections have become increasingly important during GVHD therapy, paradoxically because the success of immunosuppressive practice has led to improved survival. Infections originate from both endogenous and exogenous sources. Regimens for prevention of infection include: (a) continued surveillance monitoring for infections with reliable diagnostic testing, and (b) antimicrobial prophylaxis for those pathogens without markers that could be followed for surveillance. Repeated episodes of the same infection, diagnosis of a new life-threatening infection, or specific underlying hematologic diagnoses should prompt a look for gross immunoglobulin deficiency that could be corrected in the short term by immunoglobulin therapy. At times, measurement of CD4+ lymphocyte counts will assist in determining whether augmented prophylaxis is warranted. Since their efficacy may be limited, vaccine injections are not given during the immunosuppression associated with GVHD therapy, with the exception of influenza.

Candidemia in the 21st century

The 21st century has brought forth vast innovations in the healthcare field. The availability and use of aggressive chemotherapeutic and immunosuppressive agents as well as broad-spectrum antibacterial agents has created a large population of patients who are at increased risk of acquiring infections with fungal organisms, especially Candida species. This review will focus on the changing epidemiology of candidal bloodstream infections, its impact on healthcare and new advances in the diagnosis and treatment of candidemia.

Lung infections after cancer chemotherapy

Lung infections can be severe consequences of chemotherapy-induced immune defects. Aetiological causes of infection include bacteria (most commonly Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Nocardia species), viruses (eg, respiratory syncytial virus, parainfluenza virus, influenza virus A and B, and cytomegalovirus), and fungi (eg, Aspergillus, Fusarium, and Mucorales species, and Pneumocystis jirovecii). Most infections are caused by bacteria (especially Gram negative), but viruses are being increasingly identified. Diagnosis is difficult and frequently time-consuming. Treatment can be ineffective for many patients, particularly those with fungal infection. The greatest hope for the future is the availability of more targeted anticancer drugs that have fewer side-effects on the immune system.

Antifungal therapies in the intensive care unit

Fungal infections are increasing nationwide, paralleling increases in the number of immunosuppressed hosts. Most of the candida infections seen in the intensive care unit are likely due to iatrogenic factors such as hyperalimentation, catheters, broad-spectrum antibiotics, and postprocedure complications that are prevalent in intensive care unit patients. Delays in appropriate therapy are common and may compromise care. Fortunately, the recognition of several clinical syndromes in the intensive care unit that require specialized treatment can improve outcomes. The issue of antifungal prophylaxis has to be balanced against issues of resistance, and current guidelines are reviewed here for prophylactic use of fluconazole only in selected intensive care unit patients. Finally, several new antifungal agents are available to treat the emerging resistant fungi, with better toxic/therapeutic ratios than in the past. Thus, there are an increasing number of safer and more effective options for treating fungal infections in the intensive care unit.

Posaconazole: an oral triazole with an extended spectrum of activity

OBJECTIVE

To summarize the published clinical data on posaconazole, critically review the New Drug Application data submitted to the Food and Drug Administration, and provide information critical for evaluation and formulary positioning.

DATA SOURCES

Reported investigations were identified from MEDLINE (1966-June 30, 2008), bibliographies of manuscripts, www.clinicaltrials.gov, and www.fda.gov.

STUDY SELECTION AND DATA EXTRACTION

English-language articles were selected. All available in vitro, animal, clinical, and human studies describing the pharmacology, pharmacokinetics, pharmacodynamics, efficacy, safety, and adverse events of posaconazole were reviewed.

DATA SYNTHESIS

Posaconazole is an oral broad-spectrum triazole with activity against many yeasts and molds. Resistance to posaconazole has been reported, but has been rare to date. Posaconazole, in doses of 200 mg 3 times daily, reduced breakthrough invasive fungal infections (OR 0.30; 95% CI 0.12 to 0.71) and aspergillosis incidence (OR 0.31; 95% CI 0.13 to 0.75) in patients receiving hematopoietic stem-cell transplants compared with those receiving fluconazole. Similarly, the same regimen of posaconazole reduced invasive fungal infections (95% CI -9.7 to -2.5) and aspergillosis (CI not reported, p < 0.001) when compared with fluconazole and itraconazole in neutropenic patients. Posaconazole is noninferior to fluconazole for treatment of oropharyngeal candidiasis (95% CI -6.6 to 5.0), but necessity for this indication remains unclear, as many other treatment options exist. Smaller investigations have analyzed use of posaconazole for patients requiring salvage or alternative treatment for zygomycosis, fusariosis, cryptococcal meningitis, coccidioidomycosis, and histoplasmosis. Studies are needed to clarify efficacy for such expanded use, and therapeutic drug monitoring may improve outcomes. The most common adverse effects associated with the use of posaconazole include headache, fever, nausea, vomiting, and diarrhea.

CONCLUSIONS

Posaconazole appears to be a valuable and promising addition to the antifungal armamentarium for prophylaxis and treatment of various fungal processes. At this time, posaconazole should probably be reserved for prophylaxis in patients at high risk for invasive fungal infection, as salvage therapy in refractory or resistant infections, or for patients with intolerance to other therapies.

Antifungal therapy strategies in hematopoietic stem-cell transplant recipients: early treatment options for improving outcomes

Changes in clinical practice permit more patients to undergo hematopoietic stem-cell transplantation but also have increased the risk for invasive fungal infection (IFI) in this population. Given the difficulties in the diagnosis of fungal infection and the correlation between delays in therapy and poor outcome, earlier treatment, and prophylactic strategies are attractive options for the management of IFIs in high-risk patients. The selection of the most effective antifungal treatment strategy requires a thorough knowledge of IFI risk factors, potential causative organisms, and the safety and efficacy of appropriate antifungal agents.

Primary antifungal prophylaxis in hematopoietic stem cell transplant recipients: clinical implications of recent studies

PURPOSE OF REVIEW

Infectious complications after hematopoietic stem cell transplant, especially those caused by fungi, contribute to poor outcomes. Availability of new antifungal drugs has led to creative attempts to prevent infections caused by both yeasts and molds with new antifungal prophylaxis strategies; these studies will be reviewed.

RECENT FINDINGS

Trials evaluating mold-active azoles, posaconazole and voriconazole, demonstrate that invasive aspergillosis infections can be prevented by prophylactic therapy in patients with hematologic malignancies and after allogeneic hematopoietic stem cell transplant. However, issues arise regarding appropriate dosing and levels, drug interactions, and the importance of breakthrough infections caused by organisms that demonstrate microbiologic resistance. Other recent studies evaluating efficacy and safety of aerosolized lipid formulations of amphotericin B demonstrate promise with directed delivery to the lungs; more long-term follow-up safety information is needed to be assured that this strategy is safe late after allogeneic hematopoietic stem cell transplant, in the setting of acute and chronic graft vs. host disease.

SUMMARY

Clinicians should consider using new mold-active azole drugs for prophylaxis instead of fluconazole in allogeneic hematopoietic stem cell transplant recipients that have high risks due to prolonged neutropenia and severe graft vs. host disease. More investigations are needed to support other preventive strategies that utilize diagnostic tests and aerosolized delivery of amphotericin B formulations.

Management of infections in patients with chronic lymphocytic leukemia treated with alemtuzumab

Infection is a significant cause of morbidity and death in patients with chronic lymphocytic leukemia (CLL). Increased infectious events may arise from the multiple courses of immunosuppressive therapy and progressive deterioration of a patient's immune system over the course of disease. The humanized, anti-CD52 monoclonal antibody alemtuzumab (Campath or Campath-1H) has shown notable activity for both untreated and fludarabine-refractory CLL. The antibody not only targets malignant cells but also affects normal, healthy immune cells. The cumulative effects of the malignancy and successive courses of treatments adversely impinge on a patient's defense response to certain bacterial, fungal, and viral infections. In this review article, we provide an overview of common infectious events associated with alemtuzumab therapy in CLL. We also discuss recommendations for effectively monitoring and managing infections in CLL patients.

Compliance with anti-infective preventive measures: A multicentre survey among paediatric oncology patients

BACKGROUND

Infections are significant causes of morbidity and mortality among immunocompromised patients, but little is known about the adherence by the paediatric cancer patients to preventive anti-infective interventions.

METHODS

A voluntary and anonymised questionnaire was distributed to all patients, completing intensive anticancer therapy. Compliance was analysed by using a panel of eight commonly recommended preventive interventions and semi-quantitative scoring of adherence by the patient and/or its caretaker. Satisfaction with information and belief in the efficacy of the interventions were similarly assessed. Relationships of these factors to compliance were explored by using an overall compliance score and non-parametric correlation and/or ANOVA and logistic regression, respectively.

RESULTS

In 216 children and adolescents (mean age: 8 years; 94 girls) included in the study, compliance rates were the highest for food restriction (89.3%), the use of topic antimycotics (88.2%) and trimethoprim/sulfamethoxazole (86.6%), and the lowest for the use of face masks (68.8%), antiseptic mouth rinses (67.1%), non-absorbable antibiotic agents (66.5%) and restrictions in social contacts (65.5%). The most frequent reasons for drug non-compliance were forgetfulness and patient refusal. Compliance correlated with haematological malignancy, younger age and belief in its efficacy, but not with the perceived degree of information, burden of interventions and overall satisfaction with quality of information and medical care.

CONCLUSION

Compliance to recommended anti-infective prophylactic interventions was variable and correlated with haematological malignancy, younger age and belief in efficacy.

Trend reversal in the frequency of mycoses in hematological neoplasias: autopsy results from 1976 to 2005

INTRODUCTION

Fungal infections of internal organs are a major complication for patients with hematological neoplasias. For more than 20 years, the frequency of such mycoses has been increasing with the aggressiveness of tumor treatment.

METHODS

Autopsy findings over a 30-year period (1976 to 2005) from a single institution (Institute of Pathology, University of Essen) were retrospectively classified according to basic disease, frequency of mycoses, kind of mycoses, organs involved, hematopoietic transplantation, and cause of death.

RESULTS

340 of 1591 autopsied patients with hematological neoplasias (21.4%) revealed an invasive mycosis. The proportion increased from about 10% before 1980 to some 30% in the 1990s but fell to 21% by 2005. The frequency of mycoses decreased significantly both for transplanted patients (from 47.5% to 30.3%) and for non-transplanted patients (from 29.8% to 16.4%). The rate of deaths due to mycosis also decreased. The relative frequency of candidal mycoses went down, while aspergilloses predominated. The organ most frequently involved was the lung.

DISCUSSION

The autopsy results signal a trend reversal in the leading complication of the treatment of hematological neoplasias and lend support to the assumption that antimycotic strategies are having a positive effect.

Management of fungal infections following allogeneic stem cell transplantation

Fungal infection remains an important complication in allogeneic stem cell transplantation (allo-SCT). Since the prognosis of fungal infection is poor, prophylaxis is critical for its management; owing to recent progression in allo-SCT management and widespread use of reduced-intensity regimens, the strategy of infectious prophylaxis has also changed. Various antifungals have recently been developed and applied to clinical use. A major change in antifungal management will probably occur in the next few years.

Current and future therapeutic options in the management of invasive aspergillosis

The past decade has witnessed significant progress in the management of invasive aspergillosis. Potent, relatively non-toxic antifungal drugs, data on early chest CT scanning and the availability of a non-invasive diagnostic test (serum galactomannan) are the key advances; among these, the contribution of the recently available drugs is the most significant. Safer and earlier intervention resulting in reduced mortality and improved outcome is being demonstrated. Newer strategies enable clinicians to provide drug therapy in a highly targeted manner, such that empirical use of antifungal drugs may decline. Voriconazole has become the drug of choice for primary therapy, while posaconazole shows promise as a prophylactic drug. Echinocandins are effective for salvage therapy and are under evaluation for primary therapy. Preliminary data for efficacy of combination therapy with a mould-active azole plus an echinocandin are of promise and clinical trials are under way. Reports of emergence of less-susceptible Aspergillus spp. during azole therapy are of concern and close monitoring is needed. Remarkably, the era of polyenes appears to be nearing the end in the therapy of invasive aspergillosis. The promise of newer classes of drugs, immune-modulating therapies and vaccines are exciting future additions to the arsenal against invasive aspergillosis.

Revised definitions of invasive fungal disease from the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) Consensus Group

BACKGROUND

Invasive fungal diseases are important causes of morbidity and mortality. Clarity and uniformity in defining these infections are important factors in improving the quality of clinical studies. A standard set of definitions strengthens the consistency and reproducibility of such studies.

METHODS

After the introduction of the original European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) Consensus Group definitions, advances in diagnostic technology and the recognition of areas in need of improvement led to a revision of this document. The revision process started with a meeting of participants in 2003, to decide on the process and to draft the proposal. This was followed by several rounds of consultation until a final draft was approved in 2005. This was made available for 6 months to allow public comment, and then the manuscript was prepared and approved.

RESULTS

The revised definitions retain the original classifications of "proven," "probable," and "possible" invasive fungal disease, but the definition of "probable" has been expanded, whereas the scope of the category "possible" has been diminished. The category of proven invasive fungal disease can apply to any patient, regardless of whether the patient is immunocompromised, whereas the probable and possible categories are proposed for immunocompromised patients only.

CONCLUSIONS

These revised definitions of invasive fungal disease are intended to advance clinical and epidemiological research and may serve as a useful model for defining other infections in high-risk patients.

Does pre-exposure of Aspergillus fumigatus to voriconazole or posaconazole in vitro affect its virulence and the in vivo activity of subsequent posaconazole or voriconazole, respectively? A study in a fly model of aspergillosis

OBJECTIVES

Voriconazole and posaconazole are effective as both prophylaxis and treatment for invasive aspergillosis (IA) in immunocompromised patients. Hence, it is important to determine whether Aspergillus pre-exposure to voriconazole or posaconazole diminishes subsequent posaconazole or voriconazole activity, respectively.

METHODS

We used Aspergillus fumigatus (AF) 293 conidia with or without prior exposure to voriconazole or posaconazole [three serial passages on plates containing regular yeast extract-glucose (YAG) media, YAG+0.0625 mg/L voriconazole or YAG+0.025 mg/L posaconazole]. Toll-deficient Drosophila melanogaster flies were infected by injection, and 8 day survival was monitored. Following infection, flies were fed either regular food, food containing 1000 mg/L voriconazole (posaconazole-exposed conidia) or 1000 mg/L posaconazole (voriconazole-exposed conidia). Voriconazole and posaconazole concentrations in flies were confirmed by HPLC.

RESULTS

AF inoculation resulted in 71% mortality 8 days post-infection (median survival 4 days). Prior conidial exposure to voriconazole or posaconazole did not affect mortality (73%, P = 0.8 for voriconazole pre-exposed and 76%, P = 0.49 for posaconazole pre-exposed). Voriconazole treatment post-infection had a protective effect, reducing mortality to 42% (P = 0.0002), while prior conidial exposure to posaconazole did not alter the protective effect of voriconazole (34% 8 day mortality, P = 0.35). Likewise, posaconazole treatment post-infection reduced mortality to 36%, while prior conidial exposure to voriconazole did not alter the protective effect of posaconazole (39% mortality, P = 0.92). Median fly homogenate concentrations of voriconazole and posaconazole were 0.44 and 2.05 mg/L, respectively.

CONCLUSIONS

Prior exposure of AF to voriconazole or posaconazole did not affect the virulence of AF nor the subsequent activity of the alternate triazole in a Drosophila model of IA.

Rhino-orbital-cerebral mucormycosis and aspergillosis: differential diagnosis and treatment

In immunocompromised patients, symptoms and the pathogen spectrum of sinusitis are frequently atypical. If progressive loss of vision occurs, an infection of the anterior skull base or nasal sinuses should be considered. We report on four patients with orbit-associated symptoms. CT-imaging revealed bony defects in sinus borders to orbits or endocranium. In all the cases immediate surgical drainage was performed because complications following sinusitis were suspected. Histopathological diagnosis revealed two cases of aspergillosis and mucormycosis. The possibility of opportunistic infections by saprophytic fungi must be taken into account in immunocompromised patients, as they may endanger both vision and survival. Immediate diagnosis and therapy are essential. Nowadays, therapeutic success can be achieved due to advances in antimicrobial therapy, hyperbaric oxygen therapy and treatment of the underlying disease. Radical procedures like orbital exenteration must be considered in all cases. The current state of diagnostics, therapy and prognosis is discussed based on these case reports and the recent literature.

Advances in antifungal therapy

The prevalence of invasive fungal infections (IFIs) has increased over the past three decades owing to the increasing numbers of immunocompromised hosts. These infections are associated with significant morbidity and mortality. Recent significant advances in antifungal therapy include the broad-spectrum triazoles (voriconazole and posaconazole) and a new class of antifungals, the echinocandins (caspofungin, micafungin, and anidulafungin). New treatment strategies, such as combination therapy and pre-emptive therapy, are being investigated. There have also been significant improvements in diagnostics; the galactomannan enzyme immunoassay and the beta-glucan test are now part of the EORTC/MSG criteria for diagnosis of IFI. Despite these advances, there remain a number of unanswered questions regarding optimal management of serious fungal infections, and research continues to discover and develop new therapies and evaluate new management strategies.

Current options in antifungal pharmacotherapy

Infections caused by yeasts and molds continue to be associated with high rates of morbidity and mortality in both immunocompromised and immunocompetent patients. Many antifungal drugs have been developed over the past 15 years to aid in the management of these infections. However, treatment is still not optimal, as the epidemiology of the fungal infections continues to change and the available antifungal agents have varying toxicities and drug-interaction potential. Several investigational antifungal drugs, as well as nonantifungal drugs, show promise for the management of these infections.