Antifungal Susceptibility of Emerging Dimorphic Pathogens in the Family Ajellomycetaceae

Abstract

The susceptibilities of 24 molecularly identified dimorphic fungi belonging to the genera, , and within the family were tested against 8 standard antifungal agents using CLSI document M38-A2. Amphotericin B and posaconazole had the lowest geometric mean MICs (<0.05 μg/ml) followed by itraconazole (<0.07 μg/ml), voriconazole (<0.15 μg/ml), and isavuconazole (<0.42 μg/ml) while fluconazole was not active. Micafungin demonstrated good antifungal activity against (geometric mean minimum effective concentration [GM MEC] 0.1 μg/ml) and (GM MEC<0.017 μg/ml).

Emergomyces canadensis,a Dimorphic Fungus Causing Fatal Systemic Human Disease in North America

“…canadensis isolates found MICs elevated for fluconazole and low for itraconazole and amphotericin B. Dukik et al ( 12 ) recently reported antifungal susceptibility results for 2 Es. canadensis isolates including UAMH 7172 (reported as CBS 139872) and UAMH 10370 (reported as CBS 1398723 The authors similarly found that MICs were elevated for fluconazole and low for newer triazoles and amphotericin B ( 12 ). These findings are consistent with the antifungal susceptibility patterns reported for 50 Es.…”

Phylogeny, ecology and taxonomy of systemic pathogens and their relatives in Ajellomycetaceae (Onygenales): Blastomyces, Emergomyces, Emmonsia, Emmonsiellopsis

“…Conidia are not produced in vitro, and thus the risk of occupational inhalational exposure is considered low, although primary inoculation disease, may be possi- ble. In vitro antifungal susceptibility results suggested susceptibility to amphotericin B and extended azoles (Dukik et al 2017a). National level biosafety risk assessments for B. helicus do not yet exist.…”

“…Swollen hyphae and conidia becoming giant cells with rather thick walls, some showing broad-based budding. Scale bars: D-M = 10 lm results showed susceptibility to amphotericin B, itraconazole, voriconazole and caspofungin (Borman et al 2009;Dukik et al 2017a). However, the role of antifungal therapy is controversial, because in vivo replication does not occur (Anstead et al 2012).…”

“…Blastomyces dermatitidis can cause severe disease in immune competent hosts. In vitro susceptibility studies have reported susceptibility to amphotericin B, itraconazole, and other triazoles (Dukik et al 2017a). The Biosafety in Microbiological and Biomedical Laboratories 5th edition classifies the yeast phase of B. dermatitidis as a bio-safety level 2 pathogen and the mycelial phase as a biosafety level 3 pathogen (Anon.…”

Incidental findings of blastomycosis lung nodules in five asymptomatic patients

“…Human blastomycosis is caused by three distinct species within the Blastomyces genus . B. dermatitidis and B. gilchristii cause infections mostly in North America, whereas B. percursus has been found in South Africa and Israel [1] , [2] . The symptoms of blastomycosis range from asymptomatic infection to fulminant respiratory failure with acute respiratory distress syndrome and/or dissemination to skin, bone, and other organs.…”