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ONCOLOGY Vol 15 No 11

A steady increase in the frequency of invasive fungal infections has been observed in the past 2 decades, particularly in immunosuppressed patients. In recipients of bone marrow transplants, Candida albicans and Aspergillus fumigatus remain the primary pathogens. In many centers, however, Candida species other than C albicans now predominate, and many cases of aspergillosis are due to species other than A fumigatus. Additionally, heretofore unrecognized and/or uncommon fungal pathogens are beginning to emerge, including Blastoschizomyces capitatus, Fusarium species, Malassezia furfur, and Trichosporon beigelii. These opportunistic fungal pathogens are associated with various localized and disseminated clinical syndromes, and with substantial morbidity and mortality. These established, invasive mycoses, particularly in bone marrow transplant recipients, are the focus of this discussion. [ONCOLOGY 15(Suppl 9):11-14, 2001]

Efforts at preventing and treating fungal infection in hematopoietic stem cell transplant (HSCT) recipients must take into account the types of infections likely to be encountered during the different risk periods in hosts with different underlying risks. Given the emergence of molds as prevalent pathogens and the long duration of risk in allogeneic HSCT recipients, optimal antifungal prophylaxis would consist of treatment that can be given over a prolonged period and that would provide both anti-Candida and anti-Aspergillus activity. Optimal empiric therapy would consist of a broad-spectrum agent in the absence of more sensitive and specific methods for microbial diagnosis. Fluconazole (Diflucan) is currently the standard prophylactic agent for candidiasis, although mold-active agents and alternative strategies for polyene administration are being investigated. The gold standard for empiric therapy is currently a polyene antifungal, yet an increased appreciation for amphotericin B-resistant yeasts and molds, and less toxic mold-active alternatives, might lead to the use of other compounds in the future. The recent development of multiple alternatives emphasizes our need to establish treatment algorithms that consider both the likely pathogens and potential toxicities. [ONCOLOGY 15(Suppl 9):15-19, 2001]

With the continuing increase in clinically important fungal disease, especially seen in the neutropenic patient, the need for new and improved systemic antifungal agents marches on. A pharmacy and therapeutics committee may select an antifungal agent based on these criteria: spectrum of action, pharmacokinetic profile, toxicity, potential for resistance, and cost. A number of agents are now available for treating deep fungal infections, including amphotericin B in conventional and liposomal formulations, and the triazoles itraconazole (Sporanox) and fluconazole (Diflucan). It is important to note that there is lack of agreement in practice over what constitutes ideal therapy. The lipid formulations of amphotericin B and the improved oral solution and new intravenous formulation of itraconazole are recent additions to therapeutic options that are already having a significant influence on drug selection and treatment practices. [ONCOLOGY 15(Suppl 9):21-25, 2001]

The availability of an improved oral solution and an intravenous (IV) formulation of itraconazole (Sporanox) promises to have an effect on prevention and treatment of fungal infection in immunocompromised patients. Use of itraconazole in neutropenic patients with hematologic malignancies has been evaluated in a number of European studies. Treatment with IV followed by oral itraconazole resulted in response or stable disease in two-thirds of patients with invasive pulmonary aspergillosis. Empiric treatment with IV followed by oral solution itraconazole was at least as effective as, and significantly less toxic than, amphotericin B. Several studies of oral solution prophylaxis indicate effectiveness in prevention of fungal infection. Oral solution and IV itraconazole are useful in a variety of situations in prophylaxis, empiric therapy, and treatment of probable/confirmed infection. Itraconazole exhibits a broad spectrum of activity against Aspergillus and Candida species. It has potential advantages over fluconazole (Diflucan), which does not exhibit in vitro activity against Aspergillus and most non-albicans Candida species, and amphotericin B, which is associated with a high incidence of toxicity. Aggressive use of itraconazole and amphotericin B preparations in treatment of fungal infection at Royal Free Hospital may have reduced mortality associated with aspergillosis. [ONCOLOGY 15(Suppl 9):27-32, 2001]