Combined Melanocytic Nevus Presenting with Scalp Alopecia Associated with Alopecia Areata: Coincidence or Causal?

In the document, a 20-year-old Chinese man with a two-year history of gradual scalp hair loss, initially treated for atypical androgenetic alopecia with minoxidil without success, developed alopecia areata while under follow-up. A large patch of alopecia with a faint slate grey color and mild induration was observed on his scalp. Histologic examination revealed a compound melanocytic nevus combined with a blue nevus, which was considered a possible congenital condition that became noticeable due to the associated alopecia. Additionally, the patient had alopecia areata, which responded to intralesional steroid injections. The case highlighted the diagnostic challenge and potential misdirection in therapy when melanocytic nevi, an uncommon cause of scalp alopecia, are present. It also suggested that melanocytes might be an autoimmune target in alopecia areata, making the co-occurrence of alopecia areata and a combined melanocytic nevus particularly intriguing. No commercial support was identified for this study.