Kyrle's disease effectively treated with oral isotretinoin.

BACKGROUND: Kyrle's disease (KD) is a primary perforating dermatosis that affects more commonly 30-50 year old females, and clinically characterized by pruritic hyperkeratotic and ulcerated nodules, papules and plaques, localized on extensor surface of upper and lower limbs, and on the trunk. OBJECTIVE: To determine the effectiveness of the treatment with oral isotretinoin in KD. METHODS: We present the case of a 63-year-old woman with hyperkeratotic, erythematous-brown nodules and plaques localized on arms and legs, intensely itching; some lesions were ulcerated and discharging. Histology showed hyperplastic epidermis, cup-shaped invagination, degenerative basophilic material with plug formation. In the upper dermis, there was a dense lympho-histiocytic infiltrate. Narrow-band UVB and low dose oral corticosteroids were ineffective. Treatment with isotretinoin 20 mg/day was started with an excellent response in two months, and complete remission in the next four months. Isotretinoin was reduced to 10 mg/day for additional four months. In the next 9-month follow up, no recurrence of the disease was observed. CONCLUSIONS: Low-dose isotretinoin was very effective and well tolerated in our patient. One previous case treated with isotretinoin has been published.