When your own immune system attacks the cartilage that shapes you

Science · Published 23 October 2026 Swipe more like this →

In short: Relapsing polychondritis is a rare systemic disorder where the body's defense mechanism turns against its own structural tissues. It causes recurring cycles of intense inflammation and physical deterioration, often beginning with painful swelling in the ears or nose before potentially threatening the airway.

The pathology of relapsing polychondritis (RP) centers on an immune-mediated attack on cartilaginous and proteoglycan-rich tissues. This systemic disease is characterized by recurrent episodes of inflammation that lead to progressive anatomical deformation and functional impairment. While it primarily targets the elastic cartilage of the ears and nose, it can involve nearly any type of cartilage in the body, including the hyaline cartilage of peripheral joints and the fibrocartilage at axial sites. The condition specifically targets tissues rich in proteoglycans. It can also damage the cartilage of the tracheobronchial tree.

Clinically, over 80% of patients present with auricular chondritis (inflammation of the outer ear) and polyarthritis. However, because the disease is pleomorphic—meaning it presents in many different forms—the initial symptoms can be non-specific. This often leads to a delayed diagnosis. The typical pattern involves an acute, painful inflammatory crisis followed by spontaneous remission of varying lengths. Such cycles make early detection difficult and increase the risk of permanent damage or life-threatening complications. Diagnosis is often hindered by these non-specific early symptoms. This delay can lead to increased risks of permanent sequelae.

The disease is frequently associated with other autoimmune conditions; approximately 30% of adult patients with RP also have another disorder, with rheumatoid arthritis being the most common co-occurrence. Because the condition can impact the tracheobronchial tree, it poses a significant risk to the respiratory tract. Management often focuses on controlling these inflammatory flares, with modern therapeutic options including biologics for patients who do not respond to standard treatments. Medical professionals use laboratory and instrumental investigations to establish diagnostic criteria. These reviews also examine the role of biologics in managing refractory cases.

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