Sebaceous Adenitis

• Epidermal growth or differentiation disorder
• Inflammation of sebaceous glands, alopecia, hyperkeratosis
• Possibly immune-mediated
• Mainly affects dogs
  • Long haired show multifocal, serpiginous and annular lesions
• Microscopically:
  • Inflammation of sebaceous glands
  • Possibly orthokeratotic hyperkeratosis
  • Chronic lesions are deprived of sebaceous glands and contain mild inflammation and fibrosis at follicular isthmus