Relapsing polychondritis: a chameleon among orphan diseases.

Relapsing polychondritis (RPC) is a rare disease with recurrent episodes of inflammation of cartilage tissue leading to fibrosis and organ damage. Despite unknown etiology, there is some evidence of a genetic predisposition. The clinical presentation is heterogeneous and an association with other autoimmune disorders such as rheumatoid arthritis or different forms of vasculitis has been described. All organ systems containing cartilage can be affected, such as ear, nose, joints, trachea, aorta, and coronary arteries. Given the broad spectrum of potential manifestations, a variety of medical specialists may be involved in the management of RPC patients. As establishing the diagnosis of RPC may be difficult, an interdisciplinary approach may be preferable. Treatment options include glucocorticoids, dapsone, disease-modifying antirheumatic drugs, and biologics. Prognosis is as heterogeneous as the clinical picture, depending on the severity of organ damage. In this paper we give an overview of the current knowledge with regard to pathogenesis, clinical picture, diagnosis, and therapy of RPC.