ABSTRACT
A 13-year-old girl suddenly developed hypertrophic rough-surfaced plaques on both elbows, knees and ankles without obvious precipitating factors at 3 years of age.Because there was no subjective symptom or other discomfort, no treatment was given.Thereafter, the lesions neither faded nor spread.Skin examination revealed lesions covered with 1-2 mm-sized keratotic papules on the elbows and knees, which were clustered together and confluent in some areas.Circular keratotic plaques were observed on the ankles.Histopathology showed epidermal hyperkeratosis with mild parakeratosis, follicular keratotic plugs, acanthosis, broadened dermal papillae, telangiectasis and perivascular mononuclear infiltration in dermal papillae, infiltration of a few nonspecific cells in the superficial dermis.According to the clinical manifestations and histopathological findings, the patient was diagnosed with keratosis circumscripta, and treated with oral vitamin A and topical halometasone cream and urea-vitanmin E cream.The degree of skin hypertrophy and roughness was decreased after 15 days of treatment, but increased 1 month after drug withdrawal.