Pathology of relapsing polychondritis
- Clement J Michet, MD
Clement J Michet, MD
- Associate Professor of Medicine
- Mayo Clinic
Relapsing polychondritis (RPC) is characterized by widespread, potentially destructive, inflammatory, and degenerative lesions. Ear cartilage is classically affected, but RPC may involve cartilage and biochemically and immunologically related connective tissue structures throughout the body (table 1). (See "Clinical manifestations of relapsing polychondritis".)
This topic will review the pathologic changes associated with RPC. The pathogenesis of this disorder is discussed separately. (See "Etiology and pathogenesis of relapsing polychondritis".)
HISTOLOGY OF A TYPICAL ACTIVE EAR LESION
Biopsy of an active ear lesion is representative of pathologic changes occurring at connective tissue sites elsewhere. There is a characteristic spectrum of changes that depends upon the time the biopsy is performed.
●A pleomorphic perichondral infiltrate of lymphocytes with a variable proportion of polymorphonuclear cells, monocyte/macrophages, and plasma cells is initially observed at the chondro-dermal junction (picture 1). Lymphocytes dominate with CD4 helper T cells exceeding CD8 cytotoxic T cells . Contiguous regions of cartilage show evidence of proteoglycan depletion. Coarse granular deposits consisting primarily of immunoglobulin G (IgG) and C3 can be localized by direct immunofluorescence at the junctional site.
●As the disease progresses, the integrity of cartilage is disrupted by invading granulation tissue, which tends to sequester islands of degenerating chondrocytes and depleted matrix (picture 2). IgG and C3 may be seen throughout the matrix. Matrix metalloproteinases (MMP) are expressed in both the perichondral granulation tissue and chondrocytes . Chondrocyte apoptosis is increased in chondritis lesions and correlates with the expression of MMP-3 and cathepsin-K. Nitric oxide expression is increased, reflecting the chondrocyte production of pro-apoptotic MMPs.To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information on subscription options, click below on the option that best describes you:
- Riccieri V, Spadaro A, Taccari E, Zoppini A. A case of relapsing polychondritis: pathogenetic considerations. Clin Exp Rheumatol 1988; 6:95.
- Ouchi N, Uzuki M, Kamataki A, et al. Cartilage destruction is partly induced by the internal proteolytic enzymes and apoptotic phenomenon of chondrocytes in relapsing polychondritis. J Rheumatol 2011; 38:730.
- Hashimoto K, Arkin CR, Kang AH. Relapsing polychondritis: an ultrastructural study. Arthritis Rheum 1977; 20:91.
- Selim AG, Fulford LG, Mohiaddin RH, Sheppard MN. Active aortitis in relapsing polychondritis. J Clin Pathol 2001; 54:890.
- Chang-Miller A, Okamura M, Torres VE, et al. Renal involvement in relapsing polychondritis. Medicine (Baltimore) 1987; 66:202.
- Dalal BI, Wallace AC, Slinger RP. IgA nephropathy in relapsing polychondritis. Pathology 1988; 20:85.
- Hoang-Xaun T, Foster CS, Rice BA. Scleritis in relapsing polychondritis. Response to therapy. Ophthalmology 1990; 97:892.
- Yu EN, Jurkunas U, Rubin PA, et al. Obliterative microangiopathy presenting as chronic conjunctivitis in a patient with relapsing polychondritis. Cornea 2006; 25:621.
- Hirunwiwatkul P, Trobe JD. Optic neuropathy associated with periostitis in relapsing polychondritis. J Neuroophthalmol 2007; 27:16.