Relapsing polychondritis.

Relapsing polychondritis (RP) is a rare disease in which recurrent bouts of inflammation, in some cases followed by destruction, affect the cartilage of the ears, nose, larynx, and tracheobronchial tree. At presentation, however, arthritis is the most common manifestation and more than half the patients have no evidence of chondritis. The subsequent development of chondritis provides the correct diagnosis in patients who present with polyarthritis, ocular inflammation, or skin or audiovestibular manifestations of unknown origin. A concomitant autoimmune disease is present in one-third of patients with RP. The pathogenesis of RP involves an autoimmune response to as yet unidentified cartilage antigens followed by cartilage matrix destruction by proteolytic enzymes. The diagnosis rests on clinical grounds and can benefit from use of Michet's criteria. Anti-collagen type II and anti-matrilin-1 antibodies are neither sensitive nor specific and consequently cannot be used for diagnostic purposes. In addition to the physical evaluation and laboratory tests, useful investigations include dynamic expiratory computed tomography, magnetic resonance imaging, Doppler echocardiography, and lung function tests. Bronchoscopy has been suggested as a helpful investigation but can worsen the respiratory dysfunction. The treatment of RP is not standardized. The drug regimen should be tailored to each individual patient based on disease activity and severity. Glucocorticoid therapy is the cornerstone of the treatment of RP and is used chronically in most patients. Immunosuppressive agents are given to patients with severe respiratory or vascular involvement and to those with steroid-resistant or steroid-dependent disease. Methotrexate is often effective. Cyclophosphamide is used in severe forms.