Revisiting Riehl’s Melanosis in Korean Patients: Clinicopathological Features, Blood Chemistry, and Immunohistochemistry

Abstract

Background: Riehl’s melanosis of the face and neck has been reported in middle-aged women who have darker skin types. Recently, cases of Riehl’s melanosis have been on the rise in Korea, which might reflect the increased use of various cosmetic products and procedures. Objective: This study was designed to analyze the clinicopathological characteristics and treatment outcomes of Riehl’s melanosis in Korean patients. Methods: We closely observed 80 patients with Riehl’s melanosis diagnosed in Asan Medical Center and Hanyang University Medical Center between 2005 and 2015. A skin biopsy was analyzed in 51 patients, and a patch test was carried out in 16 patients. Results: Patients with chronic Riehl’s melanosis (＞12 months) had an increased frequency of previous laser treatments. Patients with acute Riehl’s melanosis (＜3 months) reported a previous history of dry skin, itching, or irritation as a result of the use of hair dye. Patients older than 50 years, with darker skin type, and with a longer disease duration (＞12 months) had poor response rates. Chronic Riehl’s melanosis may be preceded by repeated irritation of barrier-compromised skin, and acute Riehl’s melanosis seems to be an allergic form of Riehl’s melanosis. Conclusion: Riehl’s melanosis has different clinical manifestations according to disease duration and different treatment responses based on disease duration.