Exophiala werneckii (Horta) von Arx is the etiological agent of tinea nigra, a superficial, asymptomatic fungus infection of the stratum corneum characterized by brown to black, nonscaly macules (Rippon, 1982). The disease was originally described in Brazil in 1891. Horta isolated the pathogen in 1921 and named it Cladosporium werneckii Horta (Rippon, 1982). The painless cosmetic condition is easily treated topically with keratolytic lotion or ointments. It is noteworthy, in light of the mild nature of the disease, that misdiagnosis of the lesions as malignant melanoma has occasionally resulted in drastic and unwarranted surgical procedures (Graham and Barros-Tabita, 1971; Rippon, 1982). Although difficulty in inducing experimental infections has been reported (Graham and Barros-Tabita, 1971), Rippon (1982) states that lesions can be easily produced in abraded skin of human volunteers.
KeywordsTransmission Electron Micrograph Hyphal Growth Yeast Growth Apical Growth Hyphal Form
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