Antifungal Drugs

IntroductionFungi have been recognized as pathogens for many years. However, the incidence of fungal infections in the pediatric population has increased substantially due to the increased use of broad-spectrum antibiotics, immunosuppressive agents, hyperalimentation products, and central venous catheters in addition to the acquired immunodeficiency syndrome (AIDS) epidemic. The physician involved with the care of children should know the agents effective against these pathogens (Table 1). Amphotericin B has a long history of both efficacy and toxicity because it was the only available systemic agent for many years. With the introduction of ketoconazole, fluconazole, and itraconazole over the past decade, the decision of which agent to use has become much more difficult. Clinical trials are underway to help answer these questions, but until these are completed, the clinician must weigh the risks and benefits of therapy for each patient individually.Amphotericin BBACKGROUNDAmphotericin B is entering its fourth decade as an antifungal agent. Since its introduction in the mid-1950s, it has been the cornerstone of management of systemic fungal infections. Even with the introduction of the azoles, it continues to be the treatment of choice for many conditions.CHEMISTRY, MECHANISM OF ACTIONStreptomyces nodosus, a soil actinomycete, is the source of the amphotericins A and B. Amphotericin B is the commercially available product, and it may contain a small amount (<5%) of amphotericin A.