Relapsing PolychondritisDz

ICD-9 Code: 733.99.
ICD-10 Code: M94.1

Definition: Relapsing polychondritis is a rare disease characterized by inflammation and destruction of the cartilage. It affects auricular cartilage in 85% of patients and may also affect nasal cartilage (50% of patients), laryngotracheal cartilage (50% of patients), and other organ systems.

Etiology: Although the etiology is unknown, there is both cellular and humoral immune reactivity to cartilage, particularly types IX and XI. In addition, CD4+ T cells play an important role in the disease process, and the prevalence of HLA-DR4 is higher in patients than in controls.

Demographics: Relapsing polychondritis is a rare disorder. Although it has been described in many age groups, its incidence peaks in the fifth decade. There is no sexual predominance, and whites are most commonly affected.

Cardinal Findings: Ear pain, erythema and swelling, which may occur after minor trauma, is the initial complaint in nearly half of affected patients. Although the pinna of the ear may be grossly inflamed, the lower ear lobule is unaffected because it lacks underlying cartilage. Persistent or recurrent inflammation can lead to complete destruction of the cartilage, leaving a floppy or scarred pinna. Inflammation may also cause occlusion of the external auditory canal and hearing loss (~30% of patients). As many as one-third of patients may experience auditory or vestibular abnormalities secondary to vasculitis of the internal auditory artery.

Nasal and laryngotracheal cartilage may be affected (in ~50% of patients). Nasal cartilage destruction may result in a “saddle nose” deformity. A saddle nose deformity may also be seen in granulomatosis with polyangiitis, syphilis, or leprosy. Laryngotracheal involvement, which may present as hoarseness, stridor, or local tenderness, may be life threatening if the airway is involved.

Other organ involvement includes ocular (50%; iridocyclitis, retinal vasculitis, extraocular muscle paresis, periorbital edema, scleritis, episcleritis, conjunctivitis), articular (50%; chronic, seronegative, nonerosive, inflammatory oligoarthritis), vascular (10%; vasculitis of arteries of all sizes), and renal (10%; segmental proliferative glomerulonephritis).

Uncommon Findings: Aortic insufficiency, aortitis, and coexistent connective tissue disorders (e.g., vasculitis, JA, SLE, Sjögren’s syndrome, reactive arthritis) may occur. The overlap of Behçet’s syndrome and relapsing polychondritis has been termed MAGIC syndrome.

Diagnostic Testing: There is no diagnostic test for relapsing polychondritis. Supportive, nonspecific findings include increased ESR, anemia of chronic disease, and hypergammaglobulinemia. Antibodies to type II collagen are found in 50% of patients. Pulmonary function tests, including flow volume curves, should be performed for baseline assessment and with respiratory symptoms.

Imaging: Tomograms and CT may help determine the presence and severity of laryngotracheal involvement.

Keys to Diagnosis: Diagnosis is based on the constellation of appropriate clinical findings. Biopsy is often not needed but may be done in atypical cases. Histopathologic confirmation of cartilage inflammation and destruction supports the diagnosis and may help exclude other diagnoses.

Differential Diagnosis: Granulomatosis with polyangiitis, infection (e.g., fungal, mycobacterial, spirochetal), vasculitis, and malignancy should be considered.

Treatment: Therapy depends on the severity and extent of disease. In a minority of patients, NSAIDs and mild analgesics may suffice. Patients with more severe or refractory disease often require corticosteroids. Some patients (e.g., those with severe vasculitis, renal, or respiratory disease) may require high- dose oral corticosteroids or immunosuppressives (MTX, cyclophosphamide, cyclosporine). Laryngotracheal involvement associated with airway compromise may require surgical intervention such as excision or stenting.

Prognosis: The severity of involvement in particular organ systems determines the prognosis. Overall, a 5-year survival rate of 74% has been reported. Death is usually owing to infection, vasculitis, malignancy, or airway collapse.

BIBLIOGRAPHY

Barretto SN, Oliveira GH, Michet CJ Jr, et al. Multiple cardiovascular complications in a patient with relapsing polychondritis. Mayo ClinProc 2002;77:971–974. PMID:12233932

Letko E, Zafirakis P, Baltatzis S, et al. Relapsing polychondritis: a clinical review. Semin Arthri- tis Rheum 2002;31:384–395.PMID:12077711