ABSTRACT
This chapter describes methods to recognize and diagnose classical and new agents, and covers the taxonomic changes among clinically relevant Sporothrix species. There is a difference in susceptibility to antifungal agents among the different Sporothrix species. Accurate diagnosis depends on isolation of Sporothrix spp. from clinical specimens. Sporothrix shows delicate hyaline septate hyphae, with one of two types of conidia: hyaline, thin-walled conidia or dark-brown, thick-walled conidia. Fixed cutaneous sporotrichosis is characterized by the presence of a single, localized lesion that frequently appears on the face, neck, trunk, or arms as an ulcer, papule, or verrucous plaque. Diagnosis of sporotrichosis relies on a combination of clinical presentation, histopathological findings, serology, and culture of the etiologic agents. Histopathology findings usually reveal a mixed suppurative and granulomatous inflammatory reaction in the dermis and subcutaneous tissue, showing neutrophils, histiocytes, and plasmocytes, often with fibrosis.
