'Black dots' seen under trichoscopy are not specific for alopecia areata

Clin Exp Dermatol. 2012 Aug;37(6):615-9. doi: 10.1111/j.1365-2230.2012.04401.x. Epub 2012 Jun 8.


Background: 'Black dots' are macrocomedo-like round structures localized to the follicular ostium, and are considered a specific trichoscopic feature of alopecia areata (AA).

Aim: To characterize specific features of 'black dots', and assess their possible presence in common hair and scalp disorders.

Methods: In total, 107 patients with hair loss [30 with alopecia areata (AA), 37 with androgenetic alopecia (AGA), 17 with chronic telogen effluvium (TE), 23 with other hair and scalp diseases] and 93 healthy controls were examined, using a videodermoscope with 20-70 times magnification.

Results: There was a correlation between the black dots and the early acute phase of the various alopecia types with the presence of the black dots. Black dots were found in 11% (22/107) of patients with hair loss, including 53.3% (16/30) with AA; in 40% (2/5) of patients with severe chemotherapy-induced alopecia, and in 100% of patients with dissecting cellulitis of the scalp (n = 2), hypotrichosis simplex (n = 1), and congenital aplasia cutis (n = 1). No black dots were seen in patients with AGA or TE.

Conclusions: Black dots are not specific for AA, and may be present in other hair and scalp diseases.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Alopecia Areata / pathology
  • Child
  • Child, Preschool
  • Dermoscopy / methods*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Pigmentation Disorders / pathology*
  • Scalp*
  • Skin Diseases / pathology*
  • Young Adult