A 56 year-old man presented with 2 year-old, itchy, erythematous to brownish papules with silver scales on both legs. He had hypertension and diabetes mellitus. The clinical diagnosis was prurigo nodularis and punch biopsy was done. Microscopic examination showed a pronounced granular layer and numerous lymphocytic infiltrations of the papillary dermis with mild spongiosis (c). The final diagnosis was Kyrle’s disease with prurigo nodularis. He was treated with cyclosporin (100 mg/day) and narrowband ultraviolet-B(NB-UVB) twice/week for 12 weeks. However, there was no improvement of symptoms. Therefore, oral alitretinoin (30 mg/day) was started. After 16 weeks of treatment, skin lesions and pruritus were improved. His score on the visual analog scale for pruritus improved (from 6 to 3). His treatment with oral alitretinoin continued for 19 months and he successfully achieved complete remission without 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.