The value of trichoscopy in the differential diagnosis of scalp lesions in pemphigus vulgaris and pemphigus foliaceus.

Background: Trichoscopy is becoming increasingly popular in diagnosing hair and scalp diseases. Scalp involvement in pemphigus is common. The scalp may be the first or only site of clinical manifestation of the disease.

Objective: The aim of this study was to analyze whether trichoscopy may be useful in aiding differential diagnosis of scalp lesions in patients with pemphigus vulgaris and pemphigus foliaceus.

Methods: Trichoscopy was performed in 19 patients with scalp lesions in the course of pemphigus (9 patients with pemphigus vulgaris and 10 with pemphigus foliaceus). In all patients, the diagnosis of scalp pemphigus was confirmed by histopathology. The working magnification was 20-fold and 70-fold.

Results: The most frequently observed trichoscopy features of pemphigus lesions were: extravasations (18/19; 94.7%) and yellow hemorrhagic crusts (11/19; 57.9%). Yellow dots with whitish halo were observed in 6/19 (31.6%) patients with pemphigus. White polygonal structures were observed in pemphigus foliaceus (6/10; 60%), but not in pemphigus vulgaris. Vascular abnormalities were more frequent in pemphigus vulgaris, when compared to pemphigus foliaceus, and were associated with a severe course of disease. Linear serpentine vessels were the most frequent vascular abnormality in patients with pemphigus vulgaris and pemphigus foliaceus (77.8% and 30%, respectively).

Conclusion: Trichoscopy may serve as a useful supplementary method in the differential diagnosis of pemphigus, especially in cases of desquamative or exudative lesions limited to the scalp. Extravasations, yellow hemorrhagic crusts, yellow dots with whitish halo, white polygonal structures and linear serpentine vessels are trichoscopy features which may suggest the diagnosis of pemphigus.