Pr�emyopathische versus amyopathische Dermatomyositis

Abstract

The so-called amyopathic dermatomyositis is a rare variant of dermatomyositis which has attracted increasing interest during the last years. One finds the classical signs of dermatomyositis such as periorbital edema and erythema, erythematous macular and papular lesions localized at bony prominences (so-called Gottron's papules), generalized pruritus, photosensitivity, and a cutaneous histopathologic picture compatible with skin lesions of dermatomyositis. Crucial for the diagnosis is the exclusion of myositis by clinical examination, EMG and histology. Furthermore, longterm supervision of patients is advisable in order not to miss the appearance of early signs of myositis. The longest reported follow-up of amyopathic dermatomyositis patient is 4 years; however, it cannot be excluded that these cases will eventually culminate in classical dermatomyositis. In this paper we describe two cases and discuss the differential diagnosis and therapy; also, the term "Premyopathic dermatomyositis" is proposed, to indicate that the full picture is to be expected in most cases.