What Are the McAdam, Damiani-Levine, and Michet Criteria?

When doctors suspect relapsing polychondritis (RP), they often refer to the McAdam, Damiani-Levine, or Michet criteria. These are not definitive blood tests or imaging scans. Instead, they are classification and diagnostic aids—essentially clinical checklists—used to help recognize the disease pattern ^{[1] [2]}. Because no single laboratory test can prove you have RP, these three systems were developed to help doctors identify the characteristic combinations of inflamed cartilage and other affected tissues ^[2]. It is important to know that these criteria were largely designed to group patients for research; in the clinic, your doctor can diagnose and treat you even if you don’t perfectly match a checklist ^{[2] [3]}.

What Do the Different Systems Measure?

While all three systems look for the classic signs of RP, they require different combinations of symptoms or test results:

• McAdam Criteria: This original system focuses on six specific clinical manifestations: recurrent or bilateral inflammation of the ear cartilage (auricular chondritis), nasal cartilage inflammation, non-erosive joint inflammation (polyarthritis), eye inflammation, respiratory tract cartilage inflammation, and inner ear issues (cochlear or vestibular dysfunction) ^{[1] [4] [5]}. To satisfy the McAdam criteria, a patient must have at least three of these six features ^{[4] [5]}.
• Damiani-Levine Criteria: This system broadened the criteria to make it easier to classify RP when fewer symptoms are present, provided there is other supportive evidence. Under the Damiani-Levine system, a patient may satisfy the criteria if they have just one or more of the classic clinical features in conjunction with a confirming cartilage biopsy ^{[6] [7]}.
• Michet Criteria: This system is another clinical framework that organizes symptoms into major and minor categories, requiring specific combinations of clinical features to meet its threshold ^{[7] [6]}.

Comparison of Frameworks (Supportive Aids, Not Pass/Fail Tests)

The Role (and Limits) of Cartilage Biopsy

A biopsy (taking a small sample of cartilage to examine under a microscope) is not always required to diagnose RP, especially if you have multiple clear clinical symptoms ^{[1] [6]}. However, in the Damiani-Levine framework, a biopsy plays a central role by corroborating the clinical suspicion when only one symptom is present ^[6].

If a biopsy is considered, the ear (auricle) is often a preferred, accessible site ^[8]. Studies in specific patient groups show that ear biopsies can successfully identify inflammatory cells and cartilage damage, sometimes even when the ear is currently asymptomatic ^{[8] [9]}. In contrast, biopsies of the airway (trachea or bronchi) are less likely to provide a definitive result and carry higher risks ^[8].

However, a biopsy is not a routine, harmless procedure. It can cause pain, bleeding, infection, scarring, or permanent cosmetic deformity to the ear. Most importantly, a normal biopsy does not rule out RP, and finding inflammation does not prove RP by itself ^[2]. The decision to biopsy should be weighed carefully with a specialist to determine if it will actually change your treatment plan.

Why Clinicians Might Reach Different Conclusions

It is common for the diagnosis to remain uncertain early on. If one doctor says you meet the criteria for RP and another says you do not, it usually stems from:

• Differing Thresholds: The systems have different requirements. In a small 18-patient study, the criteria successfully identified the disease (sensitivity) in anywhere from 50% to roughly 89% of confirmed cases, depending on which exact rules were applied ^[7].
• Early or Partial Disease: These checklists were based on patients with classic, fully developed RP. In one study of 87 clinically diagnosed patients, 65.5% did not meet the Michet or Damiani thresholds because they had “partial” or “limited” disease ^[3]. Cartilage inflammation can take years to fully appear ^{[2] [3]}. Not meeting a checklist does not mean your symptoms aren’t real.
• Conditions That Resemble RP: Doctors must carefully rule out conditions that overlap with or resemble RP ^[2]. A major one is VEXAS syndrome, an acquired (not inherited) condition caused by a genetic mutation (UBA1) in blood cells, often seen in older men. VEXAS can cause fevers, skin/lung issues, and abnormal blood counts that overlap with RP ^{[10] [11]}. Other mimics include granulomatosis with polyangiitis (GPA, a type of blood vessel inflammation), infections, and side effects from certain cancer immunotherapies ^{[12] [13]}.

Urgent Warning: Because RP can weaken or narrow the airway, any new or worsening shortness of breath, noisy breathing (stridor), hoarseness, or trouble swallowing requires urgent medical assessment. Do not wait for a routine appointment. Sudden severe eye pain, vision changes, or sudden hearing loss and vertigo also require prompt specialist care.