Wickham Striae- A Characteristic Dermoscopy Finding in Lichen Planus

Abstract

The clinical and dermoscopic images described here are those of a 46-year-old female patient who presented to the Dermatology Outpatient Department with dark coloured and severely itchy lesions over both legs for the past six months that had progressively become more thicker and bigger. Clinical examination revealed hyperpigmented lichenified plaques with a slightly verrucous surface over anterior aspects of bilateral legs [Table/Fig-1]. Dermatoscopic analysis of the lesion was done which showed multiple keratin plugs, linear blood vessels in the periphery and leaf veneation like Wickham striae [Table/Fig-2]. She was managed with once daily application of a Class I topical corticosteroid (clobetasol propionate 0.05% ointment) under occlusion during the night along with a urea containing moisturiser during daytime and an oral second-generation antihistamine at night for two weeks to which she responded well. Lichen planus is an inflammatory papulosquamous disease mediated by autoreactive T-cells that target the basement membrane of skin and mucosa [1]. Varied clinical types exist of which this case is hypertrophic variant of lichen planus that characteristically presents as multiple well-circumscribed, itchy, violaceous papules and plaques, commonly over the anterior aspect of legs [2]. Dermoscopy is a very simple non invasive procedure can effectively pick it out through characteristic findings, most notable of which, is the Wickham striae. These are a network or intersecting white lines traversing through the lesion which can show different patterns like linear, radial streaming, annular, round and leaf veneation like [3], which was also seen in the present case [Table/Fig-2]. Active lesions may show dotted, globular or linear blood vessels in the periphery [Table/Fig-2] [4]. In hypertrophic lichen planus multiple keratin plugs which may be surrounded by a white halo (corn pearls) are additional findings [Table/Fig-2]. Lichen planus often presents with characteristic clinical features; hence, a skin biopsy can be circumvented in most cases. However, a clinical diagnosis can be challenging to make in a few cases mimicking other papulosquamous disorders (like psoriasis vulgaris). These cases can be easily picked up with a simple non invasive test like dermoscopy which highlights the presence of characteristic Wickham striae. This makes it a useful tool for general practitioners even in resource poor settings.

Keywords

• dermatoscopic
• lichenified plaques
• papulosquamous disease