Table 1.

Trichoscopic Findings in AA and Their Significance

Sign	Description/ Etiology	Significance a
Yellow Dots	Distention of the affected follicular infundibulum with keratinous material and sebum	Sensitive sign of AA Supports presence of non-scarring alopecia
Short Vellus Hairs	Thin and nonpigmented hairs	Sensitive sign of AA Supports regrowth when seen in AA
Black Dots	Broken pigmented hair at the level of the scalp	Specific for AA Supports presence of active disease Negative predictive marker for regrowth
Exclamation Mark Hairs	Pigmented short (1, 2mm) hairs with wide distal shaft diameter that thins proximally	Lymphocytic inflammatory infiltrate affecting the hair bulb Associated with active disease Negative predictive marker for regrowth
Tapered Hairs	Longer exclamation mark hairs (>2 mm)	Negative predictive marker for regrowth
Upright Regrowing hairs	Tapered end that thickens proximally, thicker than vellus hairs	Can be seen in many conditions Positive predictive marker for regrowth
Pigtail Hair	Short, regularly twisted hairs with short tapered end	Positive predictive marker for regrowth
Pohl-Pinkus Constrictions	Hairs with segmental thinning (constriction) or narrowing	Not specific for AA Presence of multiple segments supports cyclical disease activity

^aPredictive Markers based on Waskiel-Burnat et al