Dermatology Online Journal

Pityriasis rotunda disorder of keratinization clinically described as persistent, large, sharply defined circular patches of ichthyosiform scaling with no inflammatory changes. Patients with pityriasis rotunda may be classified into one of two groups, which are based on ethnicity, number of lesions, family history, and association with systemic diseases. A 45-year-old woman presented with asymptomatic, sharply-demarcated, round, scaly, hyperpigmented lesions on her leg that had been present for several years. Our patient did not have systemic disease or malignancy and so does not fit into groups already described.