How environmental fungi cause a range of clinical outcomes in susceptible hosts.
J Mol Biol. 2019 May 09;:
Authors: Denham ST, Wambaugh MA, Brown JCS
Environmental fungi are globally ubiquitous and human exposure is near universal. However, relatively few fungal species are capable of infecting humans, and among fungi, few exposure events lead to severe systemic or invasive infections. Systemic infections have mortality rates of up to 90%, cost the US healthcare system $7.2 billion annually, and are typically associated with immunocompromised patients. Despite this reputation, exposure to environmental fungi results in a range of outcomes, from asymptomatic latent infections to severe systemic infection. Here we discuss different exposure outcomes for five major fungal pathogens: Aspergillus, Blastomyces, Coccidiodes, Cryptococcus, and Histoplasma species. These fungi include a mold, a budding yeast, and thermal dimorphic fungi. All of these species must adapt to the dramatically changing environments over the course of disease. These dynamic environments include the human lung, which is the first exposure site for these organisms. In order to germinate and grow, fungi must defend themselves against host immune cells while germinating and growing, which risks further exposing immune-attractant molecules to the host. We discuss immune evasion strategies in during early infection, from inhibiting host immune cells and major changes in fungal cell morphology.
PMID: 31078554 [PubMed – as supplied by publisher]