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. .

IgG/IgA pemphigus reactive with desmoglein 1 with additional undetermined reactivity with epidermal basement membrane zone.

IgG/IgA pemphigus is an extremely rare subset of pemphigus, showing anti-keratinocyte cell surface antibodies of both IgG and IgA classes. Herein, we describe a unique case of IgG/IgA pemphigus with clinical features of edematous erythema and peripheral vesiculopustules. Histopathology showed the presence of subcorneal pustules and acantholytic blisters in the mid-epidermis with neutrophilic infiltration and eosinophilic spongiosis. Direct immunofluorescence of perilesional skin showed both IgG and IgA deposits to keratinocyte cell surfaces and unusual granular deposits of IgG, IgM, and C3 along basement membrane zone. On enzyme linked immunosorbent assay , the auto-antibodies were found to be reactive to desmoglein 1 antigen. Various clinical, histopathological, and immunological findings in our case overlapped with the features of IgA pemphigus, pemphigus herpetiformis, and pemphigus foliaceus. These findings indicate that IgG/IgA pemphigus may be a transitional form between IgA pemphigus and pemphigus herpetiformis, and thus provides insight into the pathogenicity of this rare disorder.