From the Research
Trichoscopy is a valuable tool in differentiating between lichen planopilaris (LPP) and discoid lupus erythematosus (DLE), with distinct features observed in each condition, as reported in the most recent study 1. The key trichoscopic findings in LPP include:
- Perifollicular scaling and erythema
- Tubular perifollicular casts (often white or silvery)
- Loss of follicular openings
- Fibrotic white dots representing scarred follicular units
- Blue-gray dots may be present in a perifollicular pattern
- Absence of vascular patterns between follicles In contrast, DLE shows:
- More prominent follicular plugging with yellow-brown dots
- Larger yellow dots
- Thick arborizing vessels between follicles
- Red dots in a scattered pattern
- Characteristic red background with white scaling
- Pigmentary changes with hyperpigmentation and hypopigmentation The presence of thick arborizing vessels and red dots is particularly helpful in distinguishing DLE from LPP, as noted in a systematic review of dermoscopic features of DLE lesions 2. Additionally, DLE tends to show more prominent follicular plugging and yellow-brown keratotic plugs, while LPP typically displays more uniform perifollicular scaling and casts around the hair follicles, as described in a study on the clinical, trichoscopic, and histopathologic features of LPP 3. These differences reflect the distinct pathophysiology of each condition, with LPP primarily affecting the follicular epithelium and DLE involving both follicular and interfollicular areas with prominent vascular changes, as discussed in a review of diagnostic and therapeutic features of LPP and frontal fibrosing alopecia 1.