A 41 year-old woman presented with multiple, 2 year-old, scattered erythematous to brownish papules with pruritus on both legs. She had diabetes mellitus. The initial clinical suspicion was reactive perforating collagenosis and punch biopsy was performed. Atrophic and ulcerative epidermis was observed. There was cup-shaped invagination of the epidermis associated with a keratin plug containing inflammatory debris and collagen fibers (d,e). Reactive perforating collagenosis and prurigo nodularis were finally diagnosed. After the use of oral cyclosporine (100 mg/day) for 4 weeks without improvement, oral alitretinoin (30 mg/day) was started. Within 5 weeks of alitretinoin treatment, her pruritus and skin lesions improved. After that, she stopped medical treatment without progression or recurrence.
A 41 year-old woman presented with localized brownish papules and patches with crust and a scaly skin lesion. She had chronic kidney disease. Her skin lesion was diagnosed as prurigo nodularis. Because of her impaired kidney function, medication that might impair renal function was limited. Treatment with oral alitretinoin was selected in a dose of 30 mg/day. Within 4 weeks of treatment, the symptoms had improved compared to conventional treatment. She continued treatment with oral alitretinoin during which the symptoms waxed and waned.