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Fungal infections of the CNS are challenging to treat and their optimal management requires knowledge of their epidemiology, host characteristics, diagnostic criteria, and therapeutic options. Aspergillus and Cryptococcus species predominate among fungal infections of the CNS. Most of these fungi are ubiquitous, but some have restricted geographical distribution. Fungal infections of the CNS usually originate from primary sites outside the CNS (eg, fungal pneumonia) or occur after inoculation (eg, invasive procedures). Most patients with these infections have immunodeficiencies, but immunocompetent individuals can also be infected through heavy exposure. The infecting fungi can be grouped into moulds, yeasts, and dimorphic fungi. Substantial progress has been made with new diagnostic approaches and the introduction of novel antifungal drugs, but fungal infections of the CNS are frequently lethal because of diagnostic delays, impaired drug penetration, resistance to antifungal treatments, and inadequate restoration of immune function. To improve outcomes, future research should advance diagnostic methods (eg, molecular detection and fungus identification), develop antifungal compounds with enhanced CNS-directed efficacy, and further investigate crucial host defence mechanisms. [ABSTRACT FROM AUTHOR]

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

Abstract: Introduction: Invasive pulmonary aspergillosis (IPA) is a leading cause of infection-associated death in immunosuppressed patients. Early detection and early administration of antifungal therapy are critical factors in improving outcome for patients with IPA. Here, we evaluated the imaging properties of a 111In-labeled cyclic peptide targeted to Aspergillus fumigatus in an immunosuppressed murine model of IPA. Methods: A cyclic peptide c(CGGRLGPFC)-NH2 was labeled with 111In by means of diethylenetriaminepentaacetic acid (DTPA). Two days after intranasal inoculation of 17.5×106 conidia of A. fumigatus, mice were injected 111In-DTPA-c(CGGRLGPFC)-NH2 intravenously. Biodistribution data were obtained at 2 h, and γ-images were acquired at 10 min and 2 h after radiotracer injection. Healthy mice were used as controls. In addition, a group of infected mice were co-injected with the radiotracer and unlabeled c(CGGRLGPFC)-NH2 to evaluate the inhibition of radiotracer''s binding to infected lungs. Autoradiographs of lungs from infected and healthy mice were compared with corresponding photographs of transaxial sections of the lung tissues stained for A. fumigatus hyphae. Results: The labeling efficiency was >98%, with specific radioactivity of up to 74 MBq/nmol peptide. Significantly higher uptake of 111In-DTPA-c(CGGRLGPFC)-NH2 was observed in the lungs of mice infected with A. fumigatus than in those of healthy mice (0.37±0.06 %ID/g vs. 0.14±0.02 %ID/g, P=.00044). Simultaneous injection with unlabeled peptide reduced radioactivity in the infected lungs by 41% (P=.0037). Increased radioactivity in the lungs of infected mice was visible in γ images at both 10 min and 2 h after radiotracer injection. Moreover, autoradiography confirmed radiotracer uptake in infected lungs, but not in the lungs of healthy mice or infected mice co-injected with unlabeled peptide. Conclusions: γ-Imaging with 111In-DTPA-c(CGGRLGPFC)-NH2 clearly delineated experimental IPA in mice. Peptides directly targeting fungi therefore may be valuable agents for noninvasive detection of opportunistic mycoses. [Copyright &y& Elsevier]

Systemic fungal Infections are increasingly reported in immuno-compromised patients with hematological malignancies, recipients of bone marrow and solid organ allografts, and patients with AIDS. Mycoses may infiltrate endocrine organs and adversely affect their function or produce metabolic complications, such as hypopituitarism, hyperthyroidism or hypothyroidism, pancreatitis, hypoadrenalism, hypogonadism, hypernatremia or hyponatremia, and hypercalcemia. Antifungal agents used for prophylaxis and/or treatment of mycoses also have adverse endocrine and metabolic effects, including hypoadrenalism, hypogonadism, hypoglycemia, dyslipidemia, hypernatremia, hypocalcemia, hyperphosphatemia, hyperkalemia or hypokalemia, and hypomagnesemia. Herein, we review how mycoses and conventional systemic antifungal treatment can affect the endocrine system and cause metabolic abnormalities. If clinicians are equipped with better knowledge of the endocrine and metabolic complications of fungal Infections and antifungal therapy, they can more readily recognize them and favorably affect outcome. [ABSTRACT FROM AUTHOR]

Abstract: We determined the in vitro galactomannan reactivity of isolates recovered from 17 patients with invasive phaeohyphomycosis, 4 of whom had positive galactomannan antigenemia. All isolates were nonreactive using the galactomannan immunoassay. Galactomannan antigenemia in patients with phaeohyphomycosis should raise the possibility of concomitant invasive aspergillosis. [Copyright &y& Elsevier]

Tumor necrosis factor α (TNF-α) blockade has emerged as a useful therapy for collagen vascular diseases or graft-vs-host disease. Fungal Infections complicating such therapy have been reported sporadically. MEDLINE and PubMed databases (from January 1, 1966, to June 1, 2007) were searched for reports of Invasive fungal Infections (IFIs) associated with the 3 available antl-TNF-α agents, le, infliximab, etanercept, and adalimumab. Of the 281 cases of IFI associated with TNF-α Inhibition, 226 (80%) were associated with Infliximab, 44 (16%) with etanercept, and 11 (4%) with adailmumab. Fungal Infections associated with infliximab occurred a median of 55 days (Interquartile range [IQR], 15-140 days) after Initiation of therapy and 3 infusions of the medication (IQR, 2-5), whereas those associated with etanercept occurred a median of 144 days (1QR, 46-240 days) after initiation of therapy. The median age of patients was 58 years (1QR, 44-68 years), and 62% were male. Use of at least I other Immunosup-pressant medication, typically a systemic corticosterold, was reported during the course of the fungal Infection In 102 (98%) of the 104 patients for whom data were available. The most prevalent IFis were histoplasmosis (n=84 [30%]), candidiasis (n=64 [23%]), and aspergiliosis (n=64 [23%]). Pneumonia was the most common pattern of Infection. Of the 90 (32%) of 281 cases for which outcome Information was available, 29 fatalities (32%) were recorded. Tumor necrosis factor a blockade Is associated with IFI across a range of host groups. A high index of suspicion In patients treated with TNF-α antagonists Is recommended because the course of such Infections can be serious or fulminant, and rapid access to health care should be provided. Surveillance of IFIs complicating TNF-a blockade and other biologic therapies Is war- ranted through well-organized prospective patient registries. [ABSTRACT FROM AUTHOR]

Summary: Posaconazale is a new triazole drug being investigated in phase III clinical trials for the treatment and prevention of invasive fungal infections. In-vitro and in-vivo studies showed that posaconazole has broad-spectrum activity against most Candida species, Cryptococcus neoformans, Aspergillus species, Fusarium species, zygomycetes, and endemic fungi. Posaconazole is given orally two to four times daily. This triazole is widely distributed in the body, metabolised mainly by the liver, and is well tolerated, even in long-term courses. Adverse events are generally mild and include headache and gastrointestinal complaints. Posaconazole has shown promising clinical efficacy against life-threatening fungal infections that are often refractory to the currently available antifungal therapies—eg, invasive aspergillosis, fusariosis, and the emerging zygomycosis. [Copyright &y& Elsevier]

Abstract: Invasive aspergillosis (IA) can occur despite prior prophylactic or empiric use of triazoles or amphotericin B (AMB). Although profound immunosuppression may account for breakthrough IA, resistance of Aspergillus to antifungals may also play a role. To examine this question, we measured the minimal inhibitory concentration of 105 Aspergillus isolates recovered from 105 cancer patients (64 with IA, 41 with Aspergillus colonization) to AMB, itraconazole (ITC), and voriconazole (VRC) using the National Committee for Clinical Laboratory Standards (NCCLS) M38-A microdilution and E-test methods. We also determined the minimal fungicidal concentration (MFC) of these agents and the minimal effective concentration (MEC) of caspofungin (CAS) using standardized methods. We then collected information regarding pre-exposure to AMB or triazoles (fluconazole, ITC, VRC) within 3 months before Aspergillus isolation. Pre-exposure of cancer patients to AMB or triazoles was associated with increased frequency of non-fumigatus Aspergillus species. Aspergillus isolates recovered from patients who previously received AMB exhibited higher E-test AMB MICs compared with isolates from patients without prior AMB exposure (P = 0.01). In addition, the AMB MICs by E-test were higher in triazole–pre-exposed patients compared with those not exposed to triazoles (P = 0.001). The ITC and VRC MICs by E-test were not affected by prior AMB or triazole exposure. Finally, neither the AMB, ITC, and VRC MICs and MFCs by NCCLS method nor CAS MECs showed such changes. In conclusion, cancer patients with positive Aspergillus cultures who are pre-exposed to AMB or triazoles have high frequency of non-fumigatus Aspergillus species. These Aspergillus isolates were found to be AMB-resistant by the more sensitive E-test method. [Copyright &y& Elsevier]