Pinpoint White Dots in the Scalp: Dermoscopic and Histopathologic Correlation
October 2010
in “
Journal of the American Academy of Dermatology
”

TLDR Small white dots on the scalp seen with a dermoscope correspond to sweat ducts and vary with different hair disorders.
The document discusses the use of dermoscopy to identify small pinpoint white dots on the scalp, which were observed in patients with various skin phototypes and hair disorders, including frontal fibrosing alopecia (FFA), lichen planopilaris (LPP), alopecia areata, androgenetic alopecia (AGA), and central centrifugal cicatricial alopecia (CCCA). Histopathologic examination revealed that these dots correspond to the epidermal portion of the eccrine sweat duct. The study involved a small number of patients: two with FFA, one with LPP, two with alopecia areata, two with AGA, and one with CCCA. The white dots were not present in patients with scalp discoid lupus erythematosus (SDLE) and folliculitis decalvans (FD), likely due to the destruction of the sweat duct by scarring. The authors suggest that the appearance of these dots is related to the contrast with the pigmented network typically seen in dark-skinned patients. They conclude that further studies are needed to understand the frequency and distribution of these structures in different populations.