The clinical differential diagnosis of lichen striatus includes linear forms of other lichenoid eruptions, including lichen planus, lichen nitidus, and lichen simplex chronicus as well as linear epidermal nevus, linear psoriasis, linear porokeratosis, tinea corporis, and verruca plana. Though lichen striatus usually resolves within a year of onset, occasionally lesions may persist for longer periods of time. In these cases, skin biopsy findings can differentiate lichen striatus from other entities such as linear epidermal nevi. Linear epidermal nevi, unlike lichen striatus, may be associated with underlying musculoskeletal, nervous, ocular, and cardiovascular anomalies and carry the potential for malignant transformation. Histopathologic features in lichen striatus include a mononuclear superficial and deep perivascular dermal infiltrate. The epidermis may demonstrate intracellular and extracellular edema with some exocytosis and parakeratosis.