Rheumatoid Arthritis
Rheumatoid arthritis (RA) is the most common rheumatic disorder, affecting approximately 1% of adults worldwide, and is 3 times more likely to occur in women than in men. RA is classically a progressive, symmetric, and deforming peripheral polyarthritis characterized by synovial inflammation and hypertrophy as well as autoantibody production. Although it can involve any joint, RA primarily affects the small joints of the hands and feet. Typically, affected joints are swollen and tender, with decreased range of motion and deformity from bone and cartilage destruction. Hand deformities (Fig 9-1) include nodules, ulnar deviation, Boutonnière deformity (abnormally flexed proximal interphalangeal [PIP] joint and extended distal interphalangeal [DIP] joint), and swan-neck deformity (abnormally hyperextended PIP and flexed DIP). Early diagnosis and treatment are critical in controlling the joint damage and associated disability.
Extra-articular Manifestations
Extra-articular involvement, which is an indicator of disease severity, occurs in about 40% of RA patients over the course of the illness. Risk factors for systemic involvement include the presence of rheumatoid factor (RF), anti–cyclic citrullinated peptide (CCP) anti-bodies, and smoking. RA can affect almost all systems; manifestations include
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subcutaneous rheumatoid nodules (in approximately 25% of patients)
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anemia of chronic disease (common in RA patients)
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increased risk of lymphoma
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Felty syndrome (seropositive RA, neutropenia, and splenomegaly)
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osteopenia and a higher risk of fractures
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pleural effusions, pulmonary nodules, and interstitial fibrosis
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cardiac disease (coronary artery disease, pericarditis and effusions, valvular disease from rheumatoid nodules, and cardiomyopathy from secondary amyloid deposition)
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peripheral vascular disease and vasculitis (small- to medium-sized vessels)
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carpal tunnel syndrome (from synovitis, compressive myelopathy, or radiculopathy)
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muscle weakness (primary or drug-induced myopathy)
Ocular involvement may include dry eye disease, scleritis, episcleritis, and corneal inflammation, melting, and infection. The ocular manifestations of RA are discussed in BCSC Section 8, External Disease and Cornea, and Section 9, Uveitis and Ocular Inflammation.
Excerpted from BCSC 2020-2021 series: Section 1 - Update on General Medicine. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.