What are the causes of polychondritis of the ears?

Causes of Polychondritis of the Ears

Relapsing polychondritis is primarily an autoimmune condition that causes inflammation and destruction of cartilaginous structures, with ear cartilage being the most commonly affected site. 1, 2

Primary Causes

• Autoimmune etiology is the predominant cause, with antibodies to type II collagen in cartilage frequently found in affected patients 3
• The condition demonstrates an equal male/female ratio with a mean age at diagnosis of 51 years 1
• Perichondral inflammation leads to cartilaginous fragmentation and destruction that eventually becomes replaced by fibrosis 1

Associated Conditions

• Approximately 30% of relapsing polychondritis cases are associated with other conditions: 4, 5
  • Systemic vasculitis 4
  • Myelodysplastic syndrome 4
  • Other autoimmune diseases 5
  • Malignancies including colon, breast, lung carcinoma, and malignant lymphoma 5

Clinical Presentation and Diagnosis

• Auricular chondritis presents as painful swelling, warmth, and redness in a portion of the auricle that characteristically spares the earlobe 6
• The condition can be mistaken for infectious cellulitis or otitis externa, leading to delayed diagnosis 2, 7
• Laboratory findings often include: 2
  • Elevated inflammatory markers (CRP, ESR)
  • Positive antinuclear antibodies (ANA)
  • Other autoantibodies may be present

Differential Diagnosis from Infectious Causes

• Key distinguishing features from infectious causes:
  • Sparing of the earlobe (which lacks cartilage) 3
  • Poor response to antibiotics 2
  • Recurrent episodes affecting the same area 2
  • Prompt response to corticosteroids 2
  • Possible involvement of other cartilaginous structures (nose, joints, respiratory tract) 1

Clinical Course and Complications

• Relapsing course is seen in 86% of patients, while continuous symptoms occur in 14% 1
• Without proper treatment, chronic disease may result in: 3
  • Flabby, droopy ear
  • Cauliflower ear deformity
  • Saddle nose deformity (if nasal cartilage is involved)
• Serious complications can occur if other cartilaginous structures are involved: 1
  • Respiratory involvement (tracheal cartilage) can lead to airway obstruction
  • Audiovestibular damage
  • Heart valve disease
  • Neurologic, ocular, and renal manifestations

Management Considerations

• Early recognition is crucial to prevent permanent cartilage damage 2
• Treatment typically includes: 1, 3
  • Salicylates and NSAIDs for milder cases
  • Systemic corticosteroids for more significant inflammation
  • Immunosuppressants (cyclophosphamide, azathioprine, methotrexate) for severe or refractory cases
  • Newer approaches including TNF-alpha antagonists for resistant cases 4

Common Pitfalls

• Misdiagnosis as infectious cellulitis or otitis externa is common, leading to delayed appropriate treatment 2, 7
• Failure to recognize the condition can lead to irreversible cartilage damage and potential life-threatening complications if respiratory involvement occurs 1
• Focusing only on the ear manifestations may cause clinicians to miss systemic involvement that requires more aggressive therapy 1