A 61 year-old man presented with several one month-old erythematous to brownish papules and nodules on the back and both legs (a,c). He had diabetes mellitus. The initial clinical suspicion was prurigo nodularis and punch biopsy was done. Microscopic examination showed hyperkeratotic epidermis with acanthosis and parakeratosis. Elongated and irregular rete ridges were observed with dense dermal perivascular infiltration (a,b). The final diagnosis was prurigo nodularis. Initially, he was treated with oral cyclosporine 100 mg/day for 4 weeks. However, relief of the symptoms was insufficient and oral alitretinoin was started at a dose of 30 mg/day. After 4 weeks of alitretinoin treatment, symptoms and skin lesions were improved, and with 8 weeks of treatment (b,d), he stopped medical treatment and achieved complete remission without recurrence.
A 42 year-old man presented with multiple scaly erythematous itchy papules on the whole body that were 12 months old. He had hypertension and diabetes mellitus. The clinical diagnosis was prurigo nodularis and treatment was started. Despite taking oral antihistamine and cyclosporine (200 mg/day) for 4 weeks, the patient’s symptoms were not improved. Medication was changed to oral alitretinoin in a dose of 30 mg/day. Within 5 weeks of treatment, symptoms had improved. The treatment of oral alitretinoin was continued for 12 weeks until complete remission and was stopped afterward without recurrence.