ABSTRACT
The outcomes of various invasive fungal infections have historically been suboptimal and for certain pathogens such as Aspergillus and Fusarium, frankly poor, with most infections ending in death. Although various pharmacologic agents have demonstrable in vitro antifungal activity, clinical responses have not been as good as one might anticipate. Several reasons have been posited. First, the early diagnosis of infection is often difficult to make, as noted in foregoing chapters. This means that treatment is often started late in the course of infection. Once the burden of organisms is high, with spread of the infection to multiple sites, and the physiological status of the patient is impaired, the prospect for successful resolution of the infection is compromised. Second, the host defenses of the infected patient are crucial for resolution of the infection, and patients who become infected have substantial compromise of such protective defenses, key to resolution of infection. Unless recovery of host defenses occurs concomitantly with antifungal therapy, prospects for successful treatment are limited. Third, substantial toxicities of several of the antifungal agents (e.g., amphotericin B) have limited the ability to administer the therapy at high enough doses or for long enough. An inadequate course of therapy seriously compromises the likelihood for treatment success.
