Hydroxyurea-induced dermatomyositis: true amyopathic dermatomyositis or dermatomyositis-like eruption?

BACKGROUND:   Hydroxyurea-induced dermatomyositis is a rare adverse reaction of long-term hydroxyurea therapy. It has been reported under different names; however, the exact classification and nomenclature of this eruption have been the subject of much debate, and a more precise term is still awaiting. Herein, we review the different aspects of this reaction and suggest a new term that might help to minimize the confusion about its nomenclature.

MATERIALS AND METHODS: We describe a 68-year-old woman who had been on long-term hydroxyurea therapy for the treatment of chronic myeloid leukemia for nine years. She presented with typical dermatomyositis-like lesions and many of the other mucocutaneous adverse effects of hydroxyurea.

RESULTS: Skin examination revealed typical Gottron's papules on the dorsa of the hands, atrophy, xerosis, acquired ichthyosis, photosensitivity, cutaneous, oral and nail hyperpigmentation, acral erythema, palmoplantar keratoderma, actinic keratoses, and leg ulcers. There was no clinical or laboratory evidence of proximal muscle weakness. Cessation of hydroxyurea was associated with remarkable improvement of the skin lesions.

CONCLUSION: Hydroxyurea-induced dermatomyositis is a rare drug-induced dermatomyositis characterized by skin lesions identical to classic dermatomyositis without clinical or laboratory evidence of myositis. We propose that the term hydroxyurea-induced amyopathic dermatomyositis that adequately describes the findings reported in this subset of patients would be more precise and specific.