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BACKGROUND: Coccidioides infections often result in chronic relapsing disease that presents a challenge to the currently available therapy. Posaconazole, an oral extended-spectrum triazole agent, has been shown in vitro and in vivo to have potent activity against this fungus. METHODS: An open-label multinational study of posaconazole, 800 mg/d, administered in divided doses for the treatment of invasive fungal infection that has been refractory to previous therapy was conducted. The data were reviewed by an independent data review committee (DRC). Fifteen patients met the criteria for proven coccidioidal infection and disease refractory to previous therapy. Success was a complete or partial response; nonsuccess was stable disease, lack of response to therapy, or undetermined response. RESULTS: The sites of coccidioidal infection were pulmonary (seven patients) and disseminated (eight patients). Patients were refractory to previous therapy (including amphotericin B with or without an azole) for a median duration of 306 days. At the end of treatment (posaconazole treatment duration, 34 to 365 days), therapy for 11 of 15 patients (73%) was considered to be successful by the DRC. Four responses were complete and seven were partial; these included five patients with pulmonary sites and six patients with disseminated sites. In responders, improvement was seen within months of the initiation of therapy. Five patients received therapy for >or= 12 months. The side effects were minimal. CONCLUSIONS: Therapy for coccidioidomycosis remains a clinical challenge, especially when patients have not responded to therapy with drugs that were recommended in treatment guidelines. The success rate (73%) achieved in this case series suggests that oral posaconazole should be considered as an important agent for the treatment of refractory coccidioidomycosis. [ABSTRACT FROM AUTHOR]

Bear in mind that systemic fungal infections can strike otherwise healthy people living in endemic areas, not just patients who are immunocompromised. Treatment may be completed within months-or it may continue for life. [ABSTRACT FROM AUTHOR]

Mice were immunosuppressed using corticosteroids and infected with conidia of Aspergillus fumigatus. Beginning 1 day after injection, mice were treated orally either with Noble agar or with SCH56592 suspended in Noble agar, or intraperitoneally with amphotericin B. SCH56592 prolonged survival and reduced lung tissue counts of A. fumigatus, while amphotericin B had marginal benefit. SCH56592 merits further development for treatment of aspergillosis. [ABSTRACT FROM PUBLISHER]

Antimicrobial resistance is a growing problem that complicates the treatment of important nosocomial and community-acquired infections. It is a worldwide problem that spans the range of human pathogens, including bacteria, fungi, and viruses. This update from the Antimicrobial Resistance Prevention Initiative (ARPI) provides a review of some important trends in antibiotic, antifungal, and antiviral resistance. Areas of focus include multidrug-resistant bacteria in the hospital setting; the growing problem of community-acquired methicillin-resistant Staphylococcus aureus; triazole and polyene resistance in nosocomial infections caused by non-Candida albicans or Aspergillus species, and the utility of in vitro susceptibility testing for these fungal infections; antiviral resistance in alpha- or beta-herpesviruses causing genital herpes or cytomegalovirus infection in immunocompromised hosts; and concerns about a possible pandemic involving avian influenza A and the importance of minimizing emergence of resistant strains of this highly pathogenic virus. The challenges in each area are different, but the general keys to addressing the growing problem of antimicrobial resistance continue to be responsible antimicrobial stewardship and the development of newer antimicrobial agents. [ABSTRACT FROM AUTHOR]

Extreme ultraviolet (EUV) radiation can be converted to visible light using tetraphenyl butadiene (TPB) as a phosphor. 1 µm films of TPB were prepared using thermal vapor deposition of the pure material and by spin coating suspensions of TPB in high-molecular-weight polystyrene/toluene solutions. Calibrated sources and detectors were used to determine the effective photon conversion efficiency of the films for incident EUV radiation in the wavelength range of $125\;{\rm nm}\le\lambda\le 200\;{\rm nm}$125nm≤λ≤200nm. After exposure to atmosphere, the efficiency of the vapor-deposited films decreased significantly, while the efficiency of the spin-coated films remained unchanged. The production of TPB films by spin coating offers the advantages of simplicity and long-term stability.

We describe a simple microfluidic system that enables the steady generation and efficient transport of aqueous drops using only a constant voltage input. Drop generation is achieved through an electrohydrodynamic dripping mechanism by which conductive drops grow and detach from a grounded nozzle in response to an electric field. The now-charged drops are transported down a ratcheted channel by contact charge electrophoresis powered by the same voltage input used for drop generation. We investigate how the drop size, generation frequency, and transport velocity depend on system parameters such as the liquid viscosity, interfacial tension, applied voltage, and channel dimensions. The observed trends are well explained by a series of scaling analyses that provide insight into the dominant physical mechanisms underlying drop generation and ratcheted transport. We identify the conditions necessary for achieving reliable operation and discuss the various modes of failure that can arise when these conditions are violated. Our results demonstrate that simple electric inputs can power increasingly complex droplet operations with potential opportunities for inexpensive and portable microfluidic systems.

Perfluorinated ionomers, in particular, Nafion, are a critical component in hydrogen fuel cells as the ion conducting binder within the catalyst layer in which it can be confined to thicknesses on the order of 10 nm or less. It is well reported that many physical properties, such as the Young's modulus, are thickness dependent when the film thickness is less than 100 nm. Here we utilize a cantilever bending methodology to quantify the swelling-induced stresses and relevant mechanical properties of Nafion films as a function of film thickness exposed to cyclic humidity. We observe a factor of 5 increase in the Young's modulus in films thinner than 50 nm and show how this increased stiffness translates to reduced swelling or hydration. The swelling stress was found to increase by a factor of 2 for films approximately 40 nm thick. We demonstrate that thermal annealing enhances the modulus at all film thicknesses and correlate these mechanical changes to chemical changes in the infrared absorption spectra.

Objectives: Meningoencephalitis caused by Cryptococcus gattii is associated with significant morbidity and the need for aggressive therapy, and often necessitates neurosurgical intervention. We adapted a previously described murine model of cryptococcal meningoencephalitis due to Cryptococcus neoformans to that caused by C. gattii., Methods: Mice were inoculated intracranially with either C. gattii (genotype VGIIa) or C. neoformans. In virulence studies, different C. gattii infecting inocula were compared with a fixed inoculum of C. neoformans, and differences were assessed by survival, brain tissue fungal burden, serum antigen titres and histopathological changes within brain tissue. For treatment, fluconazole or posaconazole (10 mg/kg orally twice daily) was initiated 24 h post-inoculation., Results: C. gattii was more virulent than C. neoformans, as evident by shorter median survival, earlier histopathological changes and higher serum antigen titres. However, no differences in fungal burden or dissemination to other organs were observed among the various groups. In treatment studies, both fluconazole and posaconazole improved the median survival of mice infected with either species. However, neither regimen improved the percentage of animals surviving to the predetermined study endpoint., Conclusions: These results demonstrate the virulence of C. gattii meningoencephalitis and the potential of this model for the assessment of new treatment strategies.

We report a case of a 27-year-old male who presented with respiratory distress that required mechanical ventilation. Transbronchial biopsy revealed adiaspores of the fungus Emmonsia crescens within granulomata, a condition known as adiaspiromycosis. The patient received amphotericin products and corticosteroids, followed by itraconazole, and made a full recovery. Emmonsia crescens is a saprobe with a wide distribution that is primarily a rodent pathogen. The clinical characteristics of the 20 cases of human pulmonary adiaspiromycosis reported since the last comprehensive case review in 1993 are described here, as well as other infections recently reported for the genus Emmonsia. Pulmonary adiaspiromycosis has been reported primarily in persons without underlying host factors and has a mild to severe course. It remains uncertain if the optimal management of severe pulmonary adiaspiromycosis is supportive or if should consist of antifungal treatment, corticosteroids, or a combination of the latter two. The classification of fungi currently in the genus Emmonsia has undergone considerable revision since their original description, including being grouped with the genus Chrysosporium at one time. Molecular genetics has clearly differentiated the genus Emmonsia from the Chrysosporium species. Nevertheless, there has been a persistent confusion in the literature regarding the clinical presentation of infection with fungi of these two genera; to clarify this matter, the reported cases of invasive Chrysosporium infections were reviewed. Invasive Chrysosporium infections typically occur in impaired hosts and can have a fatal course. Based on limited in vitro susceptibility data for Chrysosporium zonatum, amphotericin B is the most active drug, itraconazole susceptibility is strain-dependent, and fluconazole and 5-fluorocytosine are not active.

BACKGROUND. It is generally acknowledged that amphotericin B is the most effective treatment for cryptococcal meningitis. However, administration of this drug is accompanied by substantial adverse effects. This double-blind study, performed before the routine availability of highly active antiretroviral therapy, was designed to compare the efficacy and safety of liposomal amphotericin B to conventional amphotericin deoxycholate in patients with acquired immunodeficiency syndrome (AIDS) and acute cryptococcal meningitis. METHODS. Patients were randomized (ratio, 1:1:1) from multiple sites in the United States and Canada to receive either amphotericin B at 0.7 mg/kg/day (n = 87), liposomal amphotericin B at 3 mg/kg/day (n = 86), or liposomal amphotericin B at 6 mg/kg/day (n = 94). RESULTS. Efficacy was similar among all 3 treatment groups. The overall incidence of infusion-related reactions was significantly lower for both the 3 mg/kg/day and 6 mg/kg/day dosages of liposomal amphotericin B, compared with conventional amphotericin B (P < .001). Significantly fewer patients who received the 3 mg/kg/day dosage of liposomal amphotericin B developed nephrotoxicity, indicated by a doubling of the serum creatinine value, compared with recipients of conventional amphotericin B (P = .004). Overall mortality at 10 weeks was 11.6%, with no significant differences among the treatment groups. CONCLUSIONS. Liposomal amphotericin B provides an equally efficacious alternative to conventional amphotericin B deoxycholate in patients with AIDS and acute cryptococcal meningitis. Liposomal amphotericin B at a dosage of 3 mg/kg/day is accompanied by significantly fewer adverse effects.

Invasive fusariosis is a highly aggressive fungal infection associated with high mortality in heavily immunocompromised patients. Although posaconazole is efficacious as salvage therapy against infections caused by Fusarium species, concerns remain regarding this agent in the setting of reduced potency. To evaluate the efficacy of posaconazole as treatment or prophylaxis against invasive fusariosis caused by Fusarium solani, we utilized a neutropenic murine model of disseminated disease. ICR mice were administered escalating doses of posaconazole (6.25, 12.5, 25, or 50 mg/kg of body weight twice daily [BID]) by oral gavage beginning 2 days prior to inoculation in the prophylaxis studies or beginning 12 h after inoculation as treatment. Therapy was continued until day 9 postinoculation, and animals were monitored off therapy until day 15 for survival. Fungal burden was assessed as CFU in the kidneys. A clear dose-response relationship was observed, as the highest dose of posaconazole (50 mg/kg) was the most effective in prolonging survival and reducing tissue fungal burden both as prophylaxis and as treatment. This dose response was associated with high posaconazole serum concentrations as measured by bioassay. However, the extent of efficacy was also dependent on the infecting inoculum, as greater increases in survival and reductions in fungal burden were observed with the lower inocula tested. In this model high dosages of posaconazole were effective as treatment and prophylaxis against disseminated fusariosis caused by F. solani.

Cryptococcosis is a global invasive mycosis associated with significant morbidity and mortality. These guidelines for its management have been built on the previous Infectious Diseases Society of America guidelines from 2000 and include new sections. There is a discussion of the management of cryptococcal meningoencephalitis in 3 risk groups: (1) human immunodeficiency virus (HIV)-infected individuals, (2) organ transplant recipients, and (3) non-HIV-infected and nontransplant hosts. There are specific recommendations for other unique risk populations, such as children, pregnant women, persons in resource-limited environments, and those with Cryptococcus gattii infection. Recommendations for management also include other sites of infection, including strategies for pulmonary cryptococcosis. Emphasis has been placed on potential complications in management of cryptococcal infection, including increased intracranial pressure, immune reconstitution inflammatory syndrome (IRIS), drug resistance, and cryptococcomas. Three key management principles have been articulated: (1) induction therapy for meningoencephalitis using fungicidal regimens, such as a polyene and flucytosine, followed by suppressive regimens using fluconazole; (2) importance of early recognition and treatment of increased intracranial pressure and/or IRIS; and (3) the use of lipid formulations of amphotericin B regimens in patients with renal impairment. Cryptococcosis remains a challenging management issue, with little new drug development or recent definitive studies. However, if the diagnosis is made early, if clinicians adhere to the basic principles of these guidelines, and if the underlying disease is controlled, then cryptococcosis can be managed successfully in the vast majority of patients.

Invasive candidiasis has emerged as an important nosocomial infection, especially in critically ill patients. The incidence of candidaemia in Intensive Care Units (ICUs) is 5- to 10-fold higher than in the entire hospital and the crude mortality rate of patients with candidaemia is between 35% and 60%. Candida albicans remains the predominant cause of invasive candidiasis in ICUs, followed by Candida tropicalis, Candida glabrata and Candida parapsilosis. Invasive isolates of Candida spp. remain highly susceptible to fluconazole (>90% susceptible), although among Asia-Pacific countries the susceptibility rate of C. glabrata to fluconazole varies widely from 22% to 72%. Early diagnosis and prompt initiation of antifungal therapy are crucial for the effective treatment of invasive candidiasis. However, invasive candidiasis is difficult to diagnose owing to its non-specific clinical features, and delayed therapy is a major contributor to poor outcomes. Combining clinical risk factors with Candida colonisation parameters appears promising for guiding early interventions. Because of considerable regional variability, local epidemiological knowledge is critical in the effective management of invasive candidiasis among ICU patients in Asia-Pacific.

Targeted airway delivery of antifungals as prophylaxis against invasive aspergillosis may lead to high lung drug concentrations while avoiding toxicities associated with systemically administered agents. We evaluated the effectiveness of aerosolizing the intravenous formulation of voriconazole as prophylaxis against invasive pulmonary aspergillosis caused by Aspergillus fumigatus in an established murine model. Inhaled voriconazole significantly improved survival and limited the extent of invasive disease, as assessed by histopathology, compared to control and amphotericin B treatments.

Objectives: The aim of this study is to determine the efficacy and safety of posaconazole in patients with underlying renal impairment. Patients and methods We analysed the efficacy and safety of posaconazole in patients with renal impairment in a post hoc subanalysis of a Phase 3, multicentre, open-label trial in patients with invasive fungal infections (IFIs). In the Phase 3 study, 330 patients intolerant of or with IFIs refractory to standard antifungal therapy received posaconazole 800 mg daily in divided doses. In our subanalysis, 238 patients with proven/probable IFIs, including 65 patients with renal impairment (creatinine clearance < 50 mL/min or serum creatinine (sCR) level >2 mg/dL at baseline) and 173 patients with greater renal function [creatinine clearance >/= 50 mL/min (acceptable renal function)], formed the modified intent-to-treat population. Success was defined as complete or partial response, and non-success was defined as stable disease or treatment failure., Results: Overall response rates were similar in the renal impairment group (49%) and in the acceptable renal function (50%) group. Seventeen of the 41 patients with renal impairment and aspergillosis responded. Adverse events occurred in 32/65 (49%) patients with renal impairment and in 72/173 (42%) patients with acceptable renal function. The most common adverse events in both groups were nausea (14% patients with renal impairment versus 8% with acceptable renal function), altered/elevated levels of other medications (8% versus 2%), increased sCR levels (6% versus 0%), vomiting (6% versus 4%), abdominal pain (5% versus 5%) and dizziness (5% versus 1%)., Conclusions: These results suggest that posaconazole is effective and well tolerated in patients with refractory IFIs regardless of renal impairment.

Background: Aminocandin is an investigational echinocandin with excellent activity against Candida species, including Candida albicans and Candida tropicalis. However, few data are available for this agent versus Candida glabrata. We compared the in vitro potency and in vivo efficacy of aminocandin and caspofungin against clinical isolates of C. glabrata including those with reduced caspofungin susceptibility (MIC > 2 mg/L)., Methods: In vitro activity was assessed using microdilution broth susceptibility testing. Three isolates, one with a low and two with elevated caspofungin MICs, were chosen and mice were infected with C. glabrata followed by a single dose of aminocandin or caspofungin (0.5-100 mg/kg), or daily doses of caspofungin (0.07-14.3 mg/kg) begun 1 day after inoculation. Reduction in fungal burden, assessed in kidney tissue on day 8 post-inoculation, was the marker of antifungal response., Results: Aminocandin was more potent than caspofungin against each isolate with reduced caspofungin susceptibility. Mice infected with the caspofungin-susceptible isolate had significant decreases in tissue burden with low doses of either drug. Higher single doses of aminocandin (> or = 10 mg/kg) were required to reduce fungal burden against the two isolates with elevated caspofungin MICs. Single dose administration of caspofungin was ineffective against one of these isolates, and higher daily doses were required to reduce fungal burden., Conclusions: These studies suggest that aminocandin has the potential for extended interval dosing in the treatment of C. glabrata infections caused by susceptible isolates. However, higher doses may be required against isolates with reduced caspofungin susceptibility.

Background: The incidence of invasive fungal infections (IFIs) in solid organ transplant (SOT) recipients has increased during the past 20 years and is associated with significant morbidity and mortality. In this post hoc analysis of a large, open-label, multicenter study, we evaluated efficacy and safety of posaconazole, a new extended-spectrum triazole, as salvage therapy for IFIs in SOT recipients., Methods: Twenty-three SOT recipients with proven or probable IFI and evidence of disease refractory to, or intolerant of, standard antifungal therapies received posaconazole oral suspension (40 mg/mL) 800 mg daily in divided doses. An independent, blinded data-review committee assessed patient diagnosis and outcome., Results: Complete or partial response was documented in 13 of 23 (57%) SOT recipients with proven or probable IFIs, including 1 of 2 (50%) refractory patients, 5 of 8 (63%) intolerant to prior therapy, and 7 of 13 (54%) who were both. Successes by type of IFI included 7 of 12 with invasive aspergillosis, 2 of 2 with invasive fusariosis, 1 of 1 with cryptococcosis, and 1 of 2 with zygomycosis. Treatment-related adverse events (TRAEs) were reported in 12 of 23 patients. Severe TRAEs occurred in 4 of 23 patients including increased levels of cyclosporine or tacrolimus requiring immunosuppressive dose adjustments in three patients and in one, termination of posaconazole. Severe TRAEs associated with renal and liver toxicities were uncommon., Conclusion: Posaconazole was well tolerated and effective against IFIs including invasive aspergillosis, zygomycosis, fusariosis, and cryptococcosis in SOT recipients intolerant of or failing other antifungal therapies. Calcineurin inhibitor levels should be closely monitored in patients treated concomitantly with posaconazole to avoid toxicity from drug interaction.

Invasive fungal diseases (IFDs) have become major causes of morbidity and mortality among highly immunocompromised patients. Authoritative consensus criteria to diagnose IFD have been useful in establishing eligibility criteria for antifungal trials. There is an important need for generation of consensus definitions of outcomes of IFD that will form a standard for evaluating treatment success and failure in clinical trials. Therefore, an expert international panel consisting of the Mycoses Study Group and the European Organization for Research and Treatment of Cancer was convened to propose guidelines for assessing treatment responses in clinical trials of IFDs and for defining study outcomes. Major fungal diseases that are discussed include invasive disease due to Candida species, Aspergillus species and other molds, Cryptococcus neoformans, Histoplasma capsulatum, and Coccidioides immitis. We also discuss potential pitfalls in assessing outcome, such as conflicting clinical, radiological, and/or mycological data and gaps in knowledge.

Candidemia is a growing problem in tertiary care hospitals all over the world. It is generally difficult to diagnose, leads to prolonged hospitalization, has a mortality rate of around 50% and is a financial burden to healthcare systems. The different distribution profiles of Candida species underlying candidemia seen in Latin America, North America, Canada and Europe, along with the emergence of antifungal drug resistance, make it essential to optimize regional guidelines for treating hematogenous candidiasis. This article reviews the importance of candidemia epidemiology and diagnosis from region to region and highlights the antifungal agents currently available to clinicians, comparing antifungal susceptibility profiles that dominate therapeutic strategies for candidemia in specific high-risk populations., (Copyright 2008 Prous Science, S.A.U. or its licensors. All rights reserved.)

Background: Voriconazole has an important role to play in the prophylaxis and management of fungal endophthalmitis and keratitis. New-generation triazoles, including voriconazole, posaconazole and ravuconazole, have been shown in laboratory studies and clinical experience to have very good safety profiles with few side effects. Fungal eye infections, while not common in temperate climates, have been notoriously difficult to diagnose and treat, and generally result in protracted therapy with poor final outcomes. Current treatment options are far from optimal., Aims: This paper will review studies and clinical case reports published in the ophthalmic literature that address the safety of these drugs in the eye, penetration and concentration in ocular tissues and media, and efficacy in treating common pathogens implicated in fungal keratitis and endophthalmitis., Conclusions: Over 40 clinical case reports of treatment with voriconazole suggest that it may be used safely and effectively against a broad range of fungal pathogens.

Early diagnosis of invasive pulmonary aspergillosis is problematic in some patient groups due to the lack of rapid, sensitive, specific, and reliable diagnostic tests. Fungal burden and therapeutic efficacy were assessed by survival, quantitative culture (CFU counts), galactomannan enzyme immunoassay (GM-EIA), and quantitative PCR (qPCR) in a new guinea pig model of invasive pulmonary aspergillosis using an aerosol challenge. At 1 day postinfection, qPCR determined that the pulmonary fungal burden was 2 log(10) higher than that determined by CFU counting and increased significantly (P < 0.03) over time. In contrast, the tissue burden assessed by CFU counting did not rise over the course of the study. Therapy with the antifungal drug voriconazole produced statistically significant decreases in pulmonary fungal burden, as detected by CFU counting (P < 0.02), qPCR, and GM-EIA (both P < 0.0002). Daily assessment of the progression of fungal infection in serum was performed by qPCR and GM-EIA. GM-EIA demonstrated a statistically significant reduction in the fungal load on days 6 and 7 in voriconazole-treated animals compared to time-matched controls (P < 0.02). Confirmation of fungal tissue burden by two or more methods should provide a more precise account of the burden, allowing improved assessment of diagnostic and therapeutic strategies in invasive pulmonary aspergillosis.

Extended interval dosing of the echinocandins has been suggested as a potential strategy to overcome the need for daily intravenous administration. This study evaluated the therapeutic and prophylactic efficacy of single doses of aminocandin, a new echinocandin in preclinical development, in a murine model of invasive candidiasis. For therapy, groups of mice were infected with Candida albicans, followed by a single dose of aminocandin (1-15 mg/kg) or placebo (mannitol 5% w/v) administered 1 day after inoculation. As prophylaxis, mice were given a single dose (5 or 30 mg/kg) of aminocandin, caspofungin, or placebo at increasing intervals between dose and inoculation. In both treatment and prophylaxis studies, survival was assessed at 21 days post-inoculation. The reduction in fungal burden was assessed in kidney tissue on day 8 post-inoculation. For treatment, single doses of aminocandin of >/=2.5 mg/kg prolonged survival significantly. In addition, the two doses evaluated for reductions in fungal burden (5 and 15 mg/kg) revealed fungicidal activity. As prophylaxis, both aminocandin and caspofungin 5 and 30 mg/kg prolonged survival when given 7 days before inoculation. Aminocandin and caspofungin 30 mg/kg were both able to prolong survival when the interval between dose and inoculation was increased to 10 days. When this interval was extended to 14 days, only aminocandin 30 mg/kg prolonged survival and reduced fungal burden. These results demonstrate that single doses of aminocandin are effective as treatment and prophylaxis, and suggest that extended interval dosing may be a useful strategy for treating invasive candidiasis.

Background: Historically clinicians have preferred to use 'cidal' antifungal agents, particularly in critically ill patients. However, data to support the belief that the preferential use of a 'cidal' agent results in better patient outcomes has been lacking., Objective: This review examined the in vitro definitions of fungicidal and fungistatic as well as their strengths and limitations., Methods: A Medline search was performed in order to identify literature that examined the in vitro or in vivo impact of fungicidal and fungistatic activity. The study examined three common invasive fungal infections, namely cryptococcal meningitis, candidemia and invasive aspergillosis, where sufficient comparisons of fungicidal and fungistatic agents have been performed to allow for the evaluation of the clinical importance of these in vitro findings., Results and Conclusion: A clear clinical benefit of fungicidal agents over those with fungistatic activity remains elusive. Patients with cryptococcal meningitis clearly benefit from early fungicidal therapy but require long-term suppression. The data in invasive Candida sp. infections are tantalizing and suggest that fungicidal therapy may be important. However, the data for invasive aspergillosis do not support the hypothesis that fungicidal activity improves outcomes.

Serum (1-->3)-beta-D-glucan concentrations were serially measured in the presence and absence of antifungal therapy in a murine model of invasive pulmonary aspergillosis. Serum (1-->3)-beta-D-glucan was detected early during the course of infection, and reductions in this biomarker were associated with improved survival in animals treated with antifungal agents.

Objectives: The therapeutic efficacy of caspofungin alone and in combination with amphotericin B deoxycholate was evaluated in treatment of murine coccidioidomycosis., Methods: Survival and tissue burdens of the spleens and livers were used as antifungal response markers. In a monotherapy study, caspofungin was injected intraperitoneally at 0.1, 0.2, 0.5, 1 and 5 mg/kg per day on days 2 through 15. Amphotericin B deoxycholate was given at 0.1, 0.2 and 0.5 mg/kg intravenously and 1 and 5 mg/kg intraperitoneally three times per week for 2 weeks. In a combination therapy study, amphotericin B deoxycholate at 0.1 mg/kg was administered intravenously three times per week for 2 weeks, respectively, with and without caspofungin intraperitoneally given at 0.1, 0.5 and 5 mg/kg daily on days 2 through 15 post-infection., Results: The study shows that caspofungin and amphotericin B deoxycholate at > or =0.5 and > or =0.1 mg/kg, respectively, were significant in both prolongation of survival and reduction of the tissue fungal burdens of mice compared with controls. No sterilization of either organ was observed with caspofungin doses. In combination therapy, any combination of caspofungin (0.1, 0.5 and 5 mg/kg) with amphotericin B deoxycholate (0.1 mg/kg) improved the period of survival and significantly reduced spleen and liver counts compared with controls., Conclusions: This study indicates that caspofungin has efficacy against systemic coccidioidomycosis in a murine model given in combination with amphotericin B deoxycholate.

We developed a guinea pig model of cryptococcal meningitis to evaluate antifungal agents. Immunosuppressed animals challenged intracranially with Cryptococcus neoformans responded to fluconazole and voriconazole. Disease was monitored by serial cerebrospinal fluid (CSF) cultures and quantitative organ cultures. Our model produces disseminating central nervous system disease and responds to antifungal therapy.

Antimicrobial resistance is a growing problem that complicates the treatment of important nosocomial and community-acquired infections. It is a worldwide problem that spans the range of human pathogens, including bacteria, fungi, and viruses. This update from the Antimicrobial Resistance Prevention Initiative (ARPI) provides a review of some important trends in antibiotic, antifungal, and antiviral resistance. Areas of focus include multidrug-resistant bacteria in the hospital setting; the growing problem of community-acquired methicillin-resistant Staphylococcus aureus; triazole and polyene resistance in nosocomial infections caused by non-Candida albicans or Aspergillus species, and the utility of in vitro susceptibility testing for these fungal infections; antiviral resistance in alpha- or beta-herpesviruses causing genital herpes or cytomegalovirus infection in immunocompromised hosts; and concerns about a possible pandemic involving avian influenza A and the importance of minimizing emergence of resistant strains of this highly pathogenic virus. The challenges in each area are different, but the general keys to addressing the growing problem of antimicrobial resistance continue to be responsible antimicrobial stewardship and the development of newer antimicrobial agents.

Objective: Prophylactic strategies against invasive pulmonary aspergillosis are often limited by drug interactions and toxicities. Targeted airway delivery of antifungals to the lungs may avoid these pitfalls. We evaluated the effectiveness of an aerosolized nanostructured formulation of itraconazole produced by spray freezing into liquid (SFL) as prophylaxis against invasive pulmonary aspergillosis caused by A. fumigatus., Methods: Immunocompromised Balb/C mice received either itraconazole by oral gavage (Sporanox Oral Liquid [SOL] 30 mg/kg TID) or by aerosolization (SFL 30 mg/kg via 20 min aerosolizations, or control, BID). Dosing began 2 days prior to pulmonary inoculation with A. fumigatus and continued for 7 days post-inoculation. Changes in lung histopathology were also assessed. In the survival arm, mice were monitored over a 5 day period following discontinuation of therapy and survival was assessed by Kaplan-Meier analysis., Results: SFL survival (35%) was greater compared to control (10%; p=0.03) and SOL (0%; p=0.02). Histopathology demonstrated severe invasive disease involving vessels and small airways in control and SOL animals. SFL animals demonstrated colonization with some invasion predominately of large airways., Conclusions: Prophylactic aerosolization of nanostructured SFL significantly improved survival and limited invasive disease of small airways due to A. fumigatus.

In vitro studies have demonstrated that anidulafungin has greater potency than caspofungin against Candida glabrata. However, data from in vivo studies demonstrating that it has superior efficacy are lacking. The objective of this study was to compare the activities of anidulafungin and caspofungin against C. glabrata in a murine model of disseminated candidiasis. Two clinical C. glabrata isolates were used, including one with reduced caspofungin susceptibility. MICs were determined by broth microdilution in the presence and absence of sera. For the animal studies, mice were immunosuppressed with 5-fluorouracil one day prior to intravenous inoculation. Treatment with anidulafungin and caspofungin (0, 0.5, 1, 5, and 10 mg/kg of body weight per day) was begun 24 h later and was continued through day 7 postinoculation. The CFU were enumerated from kidney tissue. According to the standard microdilution methodology, anidulafungin had superior in vitro activity. However, this enhanced potency was attenuated by the addition of mouse and human sera. Caspofungin reduced the kidney fungal burden at lower doses compared to that achieved with anidulafungin in mice infected with the isolate with the lower MIC. Against the strain with the elevated caspofungin MIC, both anidulafungin and caspofungin were effective in reducing the kidney fungal burden at the higher doses studied. Despite the greater in vitro activity of anidulafungin in the absence of sera, both echinocandins were similarly effective in reducing the fungal burden in kidney tissue. The superior in vitro activity of anidulafungin did not confer enhanced in vivo efficacy against C. glabrata.

Six patients received salvage treatment with posaconazole oral suspension (800 mg/day in divided doses) for severe forms of histoplasmosis. One patient had pulmonary disease and 5 had disseminated disease. Previous antifungal therapy consisted of amphotericin B, itraconazole, fluconazole, or voriconazole. Posaconazole treatment duration for individual patients ranged from 6 weeks to 34 weeks. All patients had successful clinical outcomes with significant clinical improvements noted during the first month of therapy. Although the number of patients evaluated in this case series is small, the findings are encouraging and provide preliminary evidence that posaconazole may be a useful salvage treatment option for histoplasmosis involving a variety of infected tissues and organs.

Background: We evaluated the efficacy and safety of oral posaconazole for human immunodeficiency virus (HIV)-infected subjects with oropharyngeal candidiasis (OPC) and/or esophageal candidiasis (EC) who were clinically refractory to treatment with oral fluconazole or itraconazole., Methods: Subjects with confirmed OPC or EC who did not improve after receiving standard courses of fluconazole or itraconazole treatment were eligible for study enrollment. Subjects received either oral posaconazole (400 mg twice daily) for 3 days followed by oral posaconazole (400 mg once daily) for 25 days (regimen A; 103 patients) or oral posaconazole (400 mg twice daily) for 28 days (regimen B; 96 patients). The primary end point was cure or improvement after 28 days. Primary efficacy analyses were performed on the subset of treated subjects with refractory disease (e.g., baseline culture positive for fluconazole- or itraconazole-resistant Candida species or persistent or progressive clinical signs or symptoms consistent with treatment failure)., Results: Of the modified intent-to-treat population, 132 (75%) of 176 subjects achieved a clinical response to posaconazole treatment. Clinical response rates were similar between regimen A recipients (75.3%) and regimen B recipients (74.7%). Clinical responses occurred in 67 (73%) of 92 subjects with baseline isolates resistant to fluconazole, 49 (74%) of 66 subjects with baseline isolates resistant to itraconazole, and 42 (74%) of 57 subjects with isolates resistant to both. Clinical response was achieved in 32 (74.4%) of 43 subjects with endoscopically documented EC. The most common treatment-related adverse events were diarrhea (11%), neutropenia (7%), flatulence (6%), and nausea (6%). Eight subjects (4%) discontinued therapy as a result of a treatment-related adverse event., Conclusions: Posaconazole offers a safe and effective treatment option for HIV-infected subjects with azole-refractory OPC and/or EC.

The activities of anidulafungin and caspofungin against Candida glabrata were evaluated. MICs, 50% inhibitory concentrations (IC(50) values), and IC(90) values for anidulafungin were lower than those for caspofungin for 16 of 18 strains tested. Anidulafungin has potent in vitro activity against C. glabrata that is maintained against isolates with elevated caspofungin MICs.

Evaluating new therapeutic agents for invasive aspergillosis requires animal models that are reproducible among different laboratories. We therefore evaluated a murine model of aerosol infection in two independent laboratories and found a high level of both intra- and interlaboratory reproducibility of survival, fungal burden over time, and the efficacy of liposomal amphotericin B.

Background: Surgical techniques have been developed for mitral valve repair for a wide range of pathologies. However, excessive tissue stress and damage have been identified as etiologic factors limiting long-term durability. Before computational models to optimize valve repair can be realistically developed, in-vivo dynamic mitral valve leaflet strain data are required. However, these data do not presently exist. In the present study, a sheep model and sonomicrometry were used to compute the in-surface Eulerian strain tensor of the anterior leaflet over the cardiac cycle at varying afterloads., Methods: The anterior leaflet of nine Dorsett sheep (35 kg to 45 kg) was instrumented with nine 1-mm hemispherical piezoelectric transducers in a 15-mm square array. Three-dimensional crystal spatial positions were recorded at 250 Hz over several cardiac cycles, with peak left ventricular pressures varying from 90 mm Hg to 200 mm Hg. The in-surface Eulerian strain tensor was computed from the crystal displacements., Results: The mitral valve anterior leaflet experiences large anisotropic strains and peak strain rates of 400%/s, followed by an absolute cessation of any deformation during systole. Increasing left ventricular pressure also increased the effective leaflet stiffness but not the peak strains., Conclusions: We report the first data on the dynamic in-vivo strain tensor of a functioning mitral valve anterior leaflet, which indicated large anisotropic strains and very high strain rates. Our observations also suggest that changes in left ventricular pressure and annular geometry result in altered effective leaflet stiffness, and may be an important factor in reducing leaflet stress and as such potentially affect mitral valve repair longevity.

The difficulties in managing this potentially horrific disease, with its myriad manifestations, are immense, because host factors dramatically impact outcome. Coccidioidomycosis should warrant great respect among clinicians, because, even with dramatic improvements in therapies, outcomes remain poor. Although there have been outstanding successes with these new therapies, tragic losses after years of immense patient suffering still occur. Coccidioidomycosis is a geographically restricted fungus but is one that inflicts tremendous suffering on affected patients. In addition, because of travel and the influx of susceptible hosts, dramatic increases in patients at risk for infection are seen throughout the southwest United States. The extended-spectrum azoles, such as posaconazole and voriconazole, may prove to be more efficacious in the treatment of coccidioidomycosis than prior agents, including amphotericin B, fluconazole, and itraconazole. Additional resources are needed to conduct randomised, controlled clinical trials for the treatment of this disease.

Cryptococcus neoformans is a common cause of meningoencephalitis among AIDS patients. Several C. neoformans virulence factors have been identified, but the relative importance of particular factors is unknown. This study examined the correlation of the virulence of 18 C. neoformans var. grubii isolates from AIDS patients with the expression of several well-described virulence factors. The LD50 at 15 days after intracranial inoculation of ICR mice was <100 c.f.u. for 22 % of isolates, 100-1000 for 28 %, 1000-10,000 for 11 % and >20,000 for 39 %. Higher cryptococcal concentrations in brains were noted for isolates with lower LD50 (P = 0.002). In survival studies, no immunocompetent BALB/c mice (nu/-) infected with 3 x LD50 of three virulent isolates (LD50 = 62, 99, 1280) survived beyond 23 days, whereas 100 %, 90 % and 90 % of mice infected with 20,000 c.f.u. of three hypovirulent isolates (LD50 > 20,000) survived for 60 days (P < 0.0001). Even among BALB/c nude (nu/nu) mice, survival rates over 60 days were 100 %, 70 % and 50 %, respectively, for the hypovirulent isolates. Growth rate at 37 degrees C and capsule size within brains correlated with LD50 by univariate (P = 0.0001 and 0.028, respectively) and multivariate (P = 0.017 and 0.016, respectively) analyses. There was no correlation between LD50 and capsule size in vitro, phospholipase activity, melanin formation, proteinase activity and fluconazole MIC. In conclusion, AIDS patients are susceptible to infection by C. neoformans isolates of wide-ranging virulence, including isolates that are markedly hypovirulent. The virulence of a given isolate reflects a composite of factors rather than the contribution of a dominant factor. Growth at 37 degrees C and capsule size in vivo make particularly important contributions.

Background: Invasive fungal infections are found most frequently in immunosuppressed and critically ill hospitalized patients. Antifungal therapy is often required for long periods. Safety data from the clinical development program of the triazole antifungal agent, posaconazole, were analyzed., Methods: A total of 428 patients with refractory invasive fungal infections (n = 362) or febrile neutropenia (n = 66) received posaconazole in 2 phase II/III open-label clinical trials. Also, 109 of these patients received posaconazole therapy for > or = 6 months. Incidences of treatment-emergent, treatment-related, and serious adverse events and abnormal laboratory parameters were recorded during these studies., Results: Treatment-emergent, treatment-related adverse events were reported in 38% of the overall patient population. The most common treatment-related adverse events were nausea (8%) and vomiting (6%). Treatment-related serious adverse events occurred in 8% of patients. Low rates of treatment-related corrected QT interval and/or QT interval prolongation (1%) and elevation of hepatic enzymes (2%) were reported as adverse events. Treatment-emergent, treatment-related adverse events occurred at similar rates in patients who received posaconazole therapy for < 6 months and > or = 6 months., Conclusions: Prolonged posaconazole treatment was associated with a generally favorable safety profile in seriously ill patients with refractory invasive fungal infections. Long-term therapy did not increase the risk of any individual adverse event, and no unique adverse event was observed with longer exposure to posaconazole.

The fungal secondary metabolite gliotoxin produced by Aspergillus fumigatus has been hypothesized to be important in the development of invasive aspergillosis. In this study, we addressed this hypothesis by disrupting a nonribosomal peptide synthetase (NRPS) (encoded by gliP) predicted to be involved in gliotoxin production. Mutants with a disrupted gliP locus failed to produce gliotoxin, which confirmed the role of the NRPS encoded by gliP in gliotoxin biosynthesis. We found no morphological, developmental, or physiological defects in DeltagliP mutant strains. In addition, disruption of gliP resulted in down regulation of gene expression in the gliotoxin biosynthesis gene cluster, which was restored with addition of exogenous gliotoxin. This interesting result suggests a role for gliotoxin in regulating its own production. Culture filtrates from the DeltagliP mutant were unable to inhibit ionomycin-dependent degranulation of mast cells, suggesting a role for gliotoxin in suppressing mast cell degranulation and possibly in disease development. However, the DeltagliP mutant did not have an impact on survival or tissue burden in a murine inhalational model of invasive aspergillosis. This result suggests that gliotoxin is not required for virulence in an immunosuppressed host with an invasive pulmonary infection.

Background: Conventional amphotericin B-based antifungal therapy for invasive fusariosis in patients with a hematologic malignancy results in a > or = 70% failure rate. Posaconazole is a broad-spectrum antifungal agent with in vitro and in vivo activity against Fusarium species., Methods: In this retrospective analysis of patients from 3 open-label clinical trials, we evaluated posaconazole for the treatment of invasive fusariosis. Twenty-one patients with proven or probable invasive fusariosis who had disease refractory to or who were intolerant of standard antifungal therapy received oral posaconazole suspension (800 mg per day in divided doses) as salvage therapy., Results: Successful outcome occurred in 10 (48%) of all 21 patients. Among patients with leukemia who received posaconazole therapy for >3 days, the overall success rate was 50%; for patients who recovered from myelosuppression, the success rate was 67%, compared with 20% for those with persistent neutropenia., Conclusion: These results suggest that posaconazole is useful for the treatment of invasive fusariosis.

A 63-year-old man with a history of cirrhosis of the liver developed Candida glabrata fungemia after undergoing transjugular intrahepatic portosystemic shunt (TIPS) placement. Treatment with oral fluconazole was initially effective, but when the patient became neutropenic, subsequent blood cultures grew C. glabrata and a thrombus developed, which partially occluded the stent. Despite treatment with fluconazole, blood cultures remained positive for C. glabrata. Treatment with posaconazole resulted in clinical improvement and the patient had only intermittently positive fungal cultures for 6 weeks. A CT scan showed resolution of the inferior vena cava thrombus. Subsequently, the patient developed hepatocellular carcinoma and hepatic encephalopathy and became noncompliant with posaconazole. Blood cultures again became positive for C. glabrata. The patient died a few weeks after the diagnosis of hepatocellular carcinoma, but the cause of death was believed to be worsening liver dysfunction, not C. glabrata infection. Posaconazole had controlled the infection for about 3 months prior to his death. In conclusion, posaconazole may be a useful option in the management of prosthetic endovascular infections caused by C. glabrata.

Aerosolized evaporative precipitation into aqueous solution and spray freezing into liquid nanostructured formulations of itraconazole as prophylaxis significantly improved survival relative to commercial itraconazole oral solution and the control in a murine model of invasive pulmonary aspergillosis. Aerosolized administration of nanostructured formulations also achieved high lung tissue concentrations while limiting systemic exposure.

Immunosuppressed mice were infected intravenously with conidia of Scedosporium prolificans. Treatment was begun 1 day later with liposomal amphotericin B, caspofungin, or both drugs initiated concurrently. Amphotericin B and caspofungin were each effective, but combined therapy did not appear to offer advantages over liposomal amphotericin B alone.