Introduction: Clinical diagnosis of primary cicatricial alopecias presents difficulties. Studies regarding their trichoscopic features are scarce and mostly not comprehensive. The aim of this study is to evaluate the potential benefit of a handheld dermatoscope in clinical diagnosis of primary cicatricial alopecias.
Methods: In all, 69 patients with primary cicatricial alopecias were included in this prospective study. Preliminary diagnoses were established clinically, and confirmed by scalp biopsy in all cases. Trichoscopic examination was performed using a polarized-light handheld dermatoscope with tenfold magnification. The images were taken using a digital camera with threefold optical zoom.
Results: The following findings were significantly more common, or noted only, in particular types of primary cicatricial alopecias: "target" pattern blue-grey dots, perifollicular scaling, perifollicular cast in lichen planopilaris (n = 27); short vellus hairs, tufted hairs, crust formation, yellowish tubular scaling, pustule, red dots in folliculitis decalvans (n = 17); large keratotic yellow dots in discoid lupus erythematosus (n = 7); yellow dots, yellow dots with "three-dimensional" structure, black dots in dissecting cellulitis of the scalp (n = 6). Absence of vellus hairs was observed in patients with lichen planopilaris, frontal fibrosing alopecia, and discoid lupus erythematosus without a significant difference between the groups. Short vellus hairs were detected in all types, including frontal fibrosing alopecia (n = 7).
Conclusion: We suggest that a polarized-light handheld dermatoscope is useful for revealing several typical trichoscopic features of primary cicatricial alopecias that guide clinical diagnosis. As a novel observation, our data indicate that absence of vellus hairs is not an identifying feature for frontal fibrosing alopecia.
Keywords: Alopecia; Dermoscopy; Hair; Handheld dermatoscope; Primary cicatricial alopecia; Trichoscopy.