Equine zygomycosis caused by Conidiobolus lamprauges

Abstract

A 15-year-old Arabian mare from southern Louisiana with a 2-month history of periodic epistaxis and severe weight loss had a large, fibrosing, granulomatous mass containing numerous nodules ("kunkers") projecting dorsally into the nasopharynx, and was euthanized at the owner's request. In addition to these kunkers, the mass contained a single trematode tentatively identified as Fasciola hepatica. Several kunkers were removed, washed thoroughly in sterile water and embedded in nutrient agars; the fungus that grew out of them was identified as Conidiobolus lamprauges Drechsler (Entomophthorales: Ancylistaceae). This is the first report of C. lamprauges from any vertebrate mycosis, and only the third Conidiobolus species reported from vertebrates. Unlike many other entomophthoraleans, the fungus isolated from this mycosis grew well at 37 degrees C. The possible means by which Conidiobolus species may infect vertebrates is discussed. These mycoses probably result most often from chronic exposure during sleep to conidia discharged from fungal growth on decaying plant material in the bedding.