Author: Assoc Prof Patrick Emanuel, Dermatopathologist, Auckland, New Zealand, 2013.
Tinea nigra is a superficial mycosis caused by Hortaea werneckii.
Histology of tinea nigra
The epidermis and dermis of the acral skin infected with tinea nigra are largely unremakarkable at low power magnification (figure 1). In the superficial aspects of the stratum corneum, numerous short, segmented hyphae and spores are seen These organisms have a characteristic brown-yellow colour on routine haematoxylin and eosin sections (figure 2, arrows).