
Full text loading...
Category: Fungi and Fungal Pathogenesis; Bacterial Pathogenesis
Aspergillus as a Human Pathogen: an Evolutionary Perspective, Page 1 of 2
< Previous page | Next page > /docserver/preview/fulltext/10.1128/9781555815639/9781555814144_Chap49-1.gif /docserver/preview/fulltext/10.1128/9781555815639/9781555814144_Chap49-2.gifAbstract:
The opportunistic mould Aspergillus is one of the most ubiquitous filamentous fungi in the world. Aspergillus fumigatus is the most prevalent airborne fungal pathogen in humans and obviously the most common cause of aspergillosis, causing around 90% of infections. This chapter provides a general overview of the pathogenesis, clinical aspects, and epidemiology of aspergillosis. Invasive aspergillosis is uncommon in the healthy host, and hence there are doubts regarding the virulence of Aspergillus spp. The most significant pathogenic factor of A. fumigatus is its ubiquitous nature that increases the chance to interact with hosts presenting factors that predispose them to infection. Aspergillus is an unusual cause of onychomycosis, particularly Aspergillus sydowii and Aspergillus versicolor. The complete recognition of Aspergillus virulence could lead to advances in one's understanding of the disease and in the management of diverse clinical presentations. During the past decade the incidence of invasive infection by molds and resistance to antifungal agents have been increasing. The azole-derived antifungal agents inhibit the ergosterol biosynthesis pathway via the inhibition of 14-αsterol demethylase, the enzyme that removes the methyl group at position C-14 of precursor sterols. The study of molecular mechanisms of antifungal drug resistance is the most valuable strategy for controlling the progress of resistance and in helping develop safer and more active molecules able to avoid them.
Full text loading...
Summary of Aspergillus fumigatus resistance mechanisms to azole antifungal drugs. Differences in amino acid changes correlate with different patterns of azole resistance. ITC, itraconazole; VRC, voriconazole; RVC, ravuconazole; POS, posaconazole.
Classification of clinical syndromes caused by Aspergillus spp.
Summary susceptibility results of most frequent species of Aspergillus isolated from clinical samples a