Epidemiology of Invasive Mycoses in North America

Abstract

The incidence of invasive mycoses is increasing, especially among patients who are immunocompromised or hospitalized with serious underlying diseases. Such infections may be broken into two broad categories: opportunistic and endemic. The most important agents of the opportunistic mycoses are Candida spp., Cryptococcus neoformans, Pneumocystis jirovecii, and Aspergillus spp. (although the list of potential pathogens is ever expanding); while the most commonly encountered endemic mycoses are due to Histoplasma capsulatum, Coccidioides immitis/posadasii, and Blastomyces dermatitidis. This review discusses the epidemiologic profiles of these invasive mycoses in North America, as well as risk factors for infection, and the pathogens' antifungal susceptibility.

Cystic fibrosis, atopy, asthma and ABPA

“…2 Colonisation of the lower respiratory tract with A. fumigatus is particularly frequent in patients with CF, with a reported incidence of 57%, 54 and a prevalence of 40%. 55 Aspergillus fumigatus, a widely distributed spore-bearing fungus, causes multiple diseases in humans, [56][57][58] such as invasive pulmonary aspergillosis, aspergilloma, and different forms of hypersensitivity diseases. These include allergic asthma, characterised by a Th2 response 59,60 ; hypersensitivity pneumonitis, with Th1 response dominance, 61 and ABPA, which will be presented in later sections.…”

A comprehensive functional portrait of two heat shock factor-type transcriptional regulators involved in Candida albicans morphogenesis and virulence

“…Candida albicans is the most frequent causative agent of superficial as well as disseminated, life-threatening fungal infections [1]. The success of C. albicans as a major fungal pathogen of humans relies on a number of pathogenic traits, among which its capacity to grow and switch between at least three distinctive morphological forms: budding yeast, pseudohyphae and hyphae [2][3][4][5].…”

Direct effects of non-antifungal agents used in cancer chemotherapy and organ transplantation on the development and virulence ofCandidaandAspergillusspecies

“…This is pertinent given the current limited antifungal drug armamentarium. 1 In this article, we review current knowledge of the direct effects of conventional and investigational antineoplastic and/or immunosuppressive agents (Tables 1 and 2) on fungi. For each class of agent, we focus on the effects on fungal growth, morphological development and virulence, of the two most important pathogen genera, Candida and Aspergillus.…”

“…Specifically, modern chemotherapy for neoplastic diseases, with its immunosuppressive effects such as profound neutropenia, is a major risk factor. 1,2,4 The dysregulatory effects of antineoplastic agents on the inhibition of host leukocyte cell lineages and on other host immune responses that result in increased susceptibility to IFIs are well studied. Detailed descriptions of these immune modulatory effects are beyond the scope of this article but are comprehensively discussed elsewhere.…”

“…1,2 Although previously uncommon pathogens, including nonfumigatus Aspergillus species, Zygomycetes and Fusarium, have emerged, most invasive fungal infections (IFIs) are caused by Candida species and Aspergillus fumigatus. 1,3 Predisposing factors for IFIs are well established. Specifically, modern chemotherapy for neoplastic diseases, with its immunosuppressive effects such as profound neutropenia, is a major risk factor.…”