Malassezia Dermatitis

  • Caused by Malassezia pachydermatis
  • Yeast, normally present in external ear canal and skin
  • Clinical disease may cause yeast to proliferate and cause infection
  • Grossly:
    • Regional lesions: muzzle, ears, interdigital, perianal
    • Or generalised disease
    • Erythematous, hyperpigmented, lichenified and scaly lesions with alopecia
  • Microscopically:


Grossly, regional lesions may be seen around the muzzle, ears, interdigital, and perianal. Other common signs include erythema, hyperpigmentation, lichenified and scaly lesions with alopecia.

Microscopically, one may see;hyperkeratosis, parakeratosis, spongiotic pustular dermatitis, Acanthosis.