Sporothrichosis

Abstract

Sporothrix schenckii is currently recognized as a species complex consisting of Sporothrix brasiliensis, Sporothrix schenckii sensu stricto, Sporothrix globosa, and Sporothrix luriei. Due to divergent evolutionary process, each species possesses different virulence profiles, that allow it to thrive and persist in its niche. Currently the disease in cats is primarily caused by S. brasiliensis, S. schenckii sensu stricto and S. globosa, with cat fights and direct inoculation of the agent in the skin as the main mode of disease transmission. Expression of putative virulence factors, such as adhesins, ergosterol peroxide, melanin, proteases, extracellular vesicles and thermotolerance, determines the clinical manifestation in the feline patient, with thermotolerant S. brasiliensis exhibiting the highest pathogenicity, followed by S. schenckii sensu stricto, and S. globosa. Their ability to produce biofilm is documented, but their clinical significance remains to be elucidated. Despite comprehensive descriptions of the pathogenicity of the agent and of the disease, its prognosis remains guarded to poor, due to issues pertaining to cost, protracted treatment course, zoonotic potential and low susceptibility of some strains to antifungals.