Polychondritis, formally called relapsing polychondritis, is a rare autoimmune disease in which the body’s immune system attacks its own cartilage. It causes recurring episodes of painful inflammation in cartilage-rich structures throughout the body, particularly the ears, nose, joints, and airways. With an estimated prevalence of roughly 4.5 cases per million people, it’s uncommon enough that many doctors will go their entire career without seeing it.
The disease typically appears in people in their 40s and 50s, though it can strike at any age. Because cartilage is found in so many parts of the body, the symptoms can be widespread and sometimes confusing, often leading to delays in diagnosis.
What Causes It
The immune system mistakenly identifies a protein in cartilage, called type II collagen, as a threat. It produces antibodies against this protein and launches an inflammatory attack. Research published in the New England Journal of Medicine found these antibodies in patients during active flares, with higher antibody levels correlating with more severe disease. No antibodies were found targeting other types of collagen or cartilage components, pointing to type II collagen as the specific trigger.
Why the immune system turns on its own cartilage isn’t fully understood, but genetics play a role. Certain immune system gene variants appear far more common in people with polychondritis. One study found a particular genetic marker in 56% of patients compared to just 15.5% of healthy controls. The disease also overlaps with a recently identified genetic condition called VEXAS syndrome, which affects only men and involves cartilage, skin, and blood vessel inflammation. About 60% of people with VEXAS show symptoms that look like polychondritis.
How It Affects the Body
The hallmark symptom is ear inflammation. Up to 90% of patients experience it at some point, and for about 20% it’s the very first sign something is wrong. One or both ears become red, swollen, and tender. The earlobe, which contains no cartilage, is spared, a detail that helps distinguish it from an infection. Over time, repeated flares can destroy the ear cartilage, leaving the ears floppy or misshapen.
Nasal cartilage is the second most common target. About 24% of patients have nasal inflammation at diagnosis, and over half develop it later. The bridge of the nose becomes red, swollen, and painful. If cartilage destruction progresses, the nasal bridge collapses into what’s called a “saddle nose” deformity, a permanent, painless flattening that’s one of the disease’s most recognizable features.
Beyond the ears and nose, polychondritis can affect:
- Joints: A non-erosive arthritis that causes pain and swelling but doesn’t permanently damage the joint surfaces, unlike rheumatoid arthritis.
- Eyes: Inflammation ranging from mild redness to more serious conditions that can threaten vision.
- Airways: Inflammation of cartilage in the windpipe and voice box, which can narrow the airway. This is one of the most dangerous complications.
- Inner ear: Hearing loss, ringing in the ears, or balance problems from damage to inner ear structures.
Cardiovascular Complications
The heart and blood vessels can also be involved. Cardiac complications include inflammation of the heart’s outer lining, weakening or widening of the aorta (the body’s largest artery), and damage to heart valves. In one study of patients with cardiac involvement, about a quarter had inflammation around the heart and another quarter had thickening or widening of the aortic root. While most cardiac changes are subtle and picked up on routine testing rather than causing obvious symptoms, some can be life-threatening, including complete heart block and sudden valve failure.
How It’s Diagnosed
There is no single blood test that confirms polychondritis. Standard inflammation markers like CRP and ESR tend to rise during flares, but they’re elevated in many inflammatory conditions and aren’t specific. Antibodies to type II collagen can support the diagnosis but aren’t present in every patient. Researchers continue to search for a reliable biomarker, but none has been established yet.
Instead, diagnosis relies on recognizing a pattern of symptoms. The most widely used framework requires at least three of the following six features: bilateral ear cartilage inflammation, nasal cartilage inflammation, airway cartilage inflammation, non-erosive inflammatory arthritis, eye inflammation, and hearing or balance problems. A modified version of these criteria allows diagnosis with fewer features if a cartilage biopsy shows characteristic changes under the microscope, or if inflammation in two or more cartilage sites responds to anti-inflammatory treatment.
Because the disease is so rare and its symptoms overlap with infections, other autoimmune conditions, and even some cancers, the average patient sees multiple specialists before getting a correct diagnosis. Vitamin D deficiency is also strikingly common in these patients. One study found 91% of polychondritis patients had insufficient vitamin D levels.
Treatment and Managing Flares
Corticosteroids are the cornerstone of treatment. During an active flare, moderate to high doses of prednisone are used to bring inflammation under control quickly. Severe flares may require even higher doses. Once the flare subsides, the dose is gradually tapered to a lower maintenance level to reduce side effects from long-term steroid use.
For patients who flare frequently or can’t taper off steroids, immune-suppressing medications are added. These work by broadly dampening the overactive immune response, reducing both the frequency and severity of episodes. The goal is to use the lowest effective steroid dose possible while keeping the disease quiet.
When standard immune suppression isn’t enough, biologic therapies become an option. A French study of 41 patients with treatment-resistant polychondritis tracked outcomes across 105 courses of different biologics. Drugs that block a specific inflammatory signal called TNF were the most commonly tried. However, results were mixed: about a third of biologic courses were stopped because they didn’t work well enough, and another 18% were stopped after initially working but then losing effectiveness. Among the options studied, one class of biologic that targets a different inflammatory pathway (interleukin-6) appeared to have somewhat better staying power than others, though no biologic emerged as a clear winner for everyone.
Long-Term Outlook
Polychondritis is a chronic condition with a relapsing and remitting course. Flares come and go, sometimes separated by weeks, sometimes by years. Each episode of inflammation carries the risk of permanent cartilage damage, so the overarching strategy is to prevent flares and treat them aggressively when they occur.
Older survival data from a large patient series found 5-year survival after diagnosis was 74%, dropping to 55% at 10 years. These numbers reflect an era with fewer treatment options, and outcomes have likely improved with modern therapies. The most serious threats to survival are airway collapse from destroyed tracheal cartilage, cardiovascular complications, and infections related to immune-suppressing treatment. Patients whose disease is caught early and managed proactively tend to do better than those diagnosed after significant cartilage destruction has already occurred.