Arthritis in Sarcoidosis

Key Features

• May occur early (within 6 months of onset of symptoms) or late

• Occurs in 10–35% of patients with sarcoidosis

• Often associated with erythema nodosum

• Rarely deforming

Clinical Findings

• Usually acute in onset, but may appear insidiously and antedate other manifestations of sarcoidosis

• Knees and ankles are most commonly involved, but any joint can be affected

• Distribution of joint involvement is usually polyarticular and symmetric

• Often associated with erythema nodosum

• Commonly self-limited, resolving after several weeks or months and rarely resulting in chronic arthritis, joint destruction, or significant deformity

Diagnosis

• Contingent on demonstration of other extra-articular manifestations of sarcoidosis and biopsy evidence of noncaseating granulomas

• In chronic arthritis, radiographs show typical changes in the bones of the extremities with intact cortex and cystic changes

• Despite the clinical appearance of an inflammatory arthritis, synovial fluid often is noninflammatory (ie, < 2000 leukocytes/mcL [2.0 × 10⁹/L])

Treatment

• Usually symptomatic and supportive

• Corticosteroids, methotrexate, or TNF inhibitors may be effective in patients with severe and progressive joint disease