Less common rheumatologic disorders: Current concepts of skin and systemic manifestations.

The cutaneous manifestations of the common rheumatologic disorders, such as systemic lupus erythematosus, dermatomyositis, and systemic sclerosis, are well known. In contrast, the dermatologic findings of less common rheumatologic disorders, including Sjögren syndrome, mixed connective tissue disease, and relapsing polychondritis, are less widely known. The cutaneous manifestations of these connective tissue disorders are reviewed.