Publications by authors named "Peter Troke"

Invasive aspergillosis (IA) remains a major cause of morbidity in immunocompromised hosts. This is due to the inability of the host immunity to respond appropriately to Aspergillus. An established risk factor for IA is neutropenia that is encountered by patients undergoing chemotherapy.

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An improved number of anti-fungal drugs are currently available for the treatment of invasive aspergillosis (IA). While serial galactomannan index (GMI) measurement can be used to monitor response to treatment, the extent to which different anti-fungal regimens can affect galactomannan levels is unknown. In 147 IA patients receiving either voriconazole (VCZ) or conventional amphotericin B (CAB) in a multicentre clinical trial, we performed post-hoc analyses of GMI trends in relation to outcomes.

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Understanding the tissue penetration of systemically administered antifungal agents is critical for a proper appreciation of their antifungal efficacy in animals and humans. Both the time course of an antifungal drug and its absolute concentrations within tissues may differ significantly from those observed in the bloodstream. In addition, tissue concentrations must also be interpreted within the context of the pathogenesis of the various invasive fungal infections, which differ significantly.

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Objectives: The underlying mechanism for amphotericin B-induced acute kidney injury (AKI) remains poorly understood and may be immunologically mediated. We assessed whether the development of nephrotoxicity is linked to a distinct cytokine profile in patients receiving amphotericin B deoxycholate (AmBD).

Patients And Methods: In 58 patients who received AmBD, circulating serum interleukin (IL)-6, IL-8 and IL-10 were measured at baseline, week 1 and week 2 of antifungal treatment and correlated to the development of renal impairment.

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The monitoring and prediction of treatment responses to invasive aspergillosis (IA) are difficult. We determined whether serum galactomannan index (GMI) trends early in the course of disease may be useful in predicting eventual clinical outcomes. For the subjects recruited into the multicenter Global Aspergillosis Study, serial GMIs were measured at baseline and at weeks 1, 2, and 4 following antifungal treatment.

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Voriconazole is approved for treating invasive fungal infections. We examined voriconazole exposure-response relationships for patients from nine published clinical trials. The relationship between the mean voriconazole plasma concentration (C(avg)) and clinical response and between the free C(avg)/MIC ratio versus the clinical response were explored using logistic regression.

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Background: Monitoring treatment response in invasive aspergillosis is challenging, because an immunocompromised host may not exhibit reliable symptoms and clinical signs. Cytokines play a pivotal role in mediating host immune response to infection; therefore, the profiling of biomarkers may be an appropriate surrogate for disease status.

Methods: We studied, in a cohort of 119 patients with invasive aspergillosis who were recruited in a multicenter clinical trial, serum interleukin (IL)-6, IL‐8, IL‐10, interferon‐γ, and C‐reactive protein (CRP) trends over the first 4 weeks of therapy and correlated these trends to clinical outcome parameters.

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The outcomes for 73 invasive fusariosis patients treated with voriconazole were investigated. Patients with proven (n = 67) or probable (n = 6) infections were identified from the voriconazole clinical database (n = 39) and the French National Reference Center for Mycoses and Antifungals database (n = 34). Investigator-determined success was a complete or partial response.

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Background: Voriconazole is used to manage invasive fungal diseases in recipients of an allogeneic haematopoietic stem cell transplant (HSCT) after myeloablative treatment. Little is known about the pharmacokinetics (PK) of voriconazole in this population, who also receive cyclosporine A.

Methods: Patients admitted for an allogeneic HSCT were eligible for the study.

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Background: Invasive aspergillosis is a devastating infection with attributable mortality of 40% despite antifungal therapy. In animal models of aspergillosis, deficiency of mannose-binding lectin (MBL), a pattern recognition receptor that activates complement, is a susceptibility factor. MBL deficiency occurs in 20%-30% of the population.

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The susceptibility of 1763 yeast isolates (from 22 species and seven genera) was tested using Clinical and Laboratory Standards Institute M27-A2 microdilution methodology. Candida spp. predominated (97.

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Introduction: Fungal pathogens from the voriconazole trials were identified and tested for susceptibility at two reference laboratories.

Methods: MICs were measured using CLSI M38-A 48 h microdilution methodology.

Results: Moulds from 29 genera and 38 species were isolated from 18 countries.

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The efficacy of voriconazole in 107 patients with scedosporiosis was analyzed. Principal infection sites were the lungs/sinuses (24%), central nervous system (CNS) (20%), and bone (18%), while 21% of patients had disseminated infection. Solid organ transplantation (22%), hematological malignancy (21%), and surgery/trauma (15%) were the predominant underlying conditions.

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Recently, improved response and survival rates in patients treated with voriconazole and neurosurgery for central nervous system (CNS) aspergillosis have been reported. We assessed retrospectively the outcome in 17 patients with definite or probable CNS aspergillosis treated with amphotericin B alone (n = 15) or in combination with 5-fluorocytosine (n = 3) or itraconazole (n = 2). Four patients underwent neurosurgery.

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Background: Computed tomography (CT) of the chest may be used to identify the halo sign, a macronodule surrounded by a perimeter of ground-glass opacity, which is an early sign of invasive pulmonary aspergillosis (IPA). This study analyzed chest CT findings at presentation from a large series of patients with IPA, to assess the prevalence of these imaging findings and to evaluate the clinical utility of the halo sign for early identification of this potentially life-threatening infection.

Methods: Baseline chest CT imaging findings from 235 patients with IPA who participated in a previously published study were systematically analyzed.

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This study investigated the relationship between plasma voriconazole concentrations (pVC) and risk of visual adverse events (VAEs) or liver function test (LFT) abnormalities using longitudinal logistic regression. Seven-day mean pVC were calculated from 2,925 plasma samples (1,053 patients); in each 7-day period, the presence or absence of VAEs/abnormal LFTs was analyzed as a binary outcome variable. There was a relationship between pVC and risk of VAE (P = .

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Background: In a previous randomized trial of voriconazole versus amphotericin B deoxycholate for primary therapy of invasive aspergillosis, voriconazole demonstrated superior efficacy and better survival. In that trial, treatment with voriconazole or amphotericin B deoxycholate could be followed with other licensed antifungal therapies (OLAT). Here, we report the impact of OLAT on the outcome of patients with invasive aspergillosis.

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The mortality of central nervous system (CNS) aspergillosis approaches 100%, requiring improved therapies. Voriconazole gives superior efficacy and survival in invasive aspergillosis, compared with amphotericin B. Also, in contrast to other antifungal drugs, voriconazole penetrates well into the CNS.

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We characterized voriconazole concentrations in the cerebrospinal fluid (CSF) of immunocompetent guinea pigs and patients with invasive fungal infections. In animals, after receipt of oral doses of 4 or 10 mg/kg every 8 h, the mean ratios of CSF to plasma total and free drug concentration were 0.68 and 1.

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Background: Voriconazole is a broad-spectrum triazole that is active against aspergillus species. We conducted a randomized trial to compare voriconazole with amphotericin B for primary therapy of invasive aspergillosis.

Methods: In this randomized, unblinded trial, patients received either intravenous voriconazole (two doses of 6 mg per kilogram of body weight on day 1, then 4 mg per kilogram twice daily for at least seven days) followed by 200 mg orally twice daily or intravenous amphotericin B deoxycholate (1 to 1.

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