Resistant pityriasis lichenoides et varioliformis acuta in a 3-year-old boy: successful treatment with methotrexate.

Pityriasis lichenoides et varioliformis acuta (PLEVA) represents the acute clinical subtype of pityriasis lichenoides (PL) and its occurrence is relatively common during childhood. Diagnosis and treatment may sometimes pose certain difficulties. We present the recalcitrant case of a 3-year-old boy with an asymptomatic polymorphic eruption consisting of multiple, scattered, 0.5 cm, round to ovoid, erythematous papules covered in places with a fine scale, vesicles and superficial erosions with thick hemorrhagic crusts. The correlation of the clinical features with the lesional histopathology favored the diagnosis of PLEVA. No first-line treatment scheme succeeded in controlling the eruption of new lesions. The only therapeutic approach that eventually managed to cease the disease evolution was the combination of prednisolone and methotrexate.