What

• Autoimmune damage to synovium → periarticular osteopenia → bone erosions, joint space narrowing, & joint subluxation of the small joints

Epidemiology

• F > M, affecting 0.2 to 1% of developed world
• HLA-DRB1 is strongest genetic risk factor
• Cigarette smoking is strongest environmental risk factor

Presentation

• Polyarticular inflammatory arthritis + ___

• Dermatologic: extensor-surface nodules > neutrophilic dermatosis

• Ocular: secondary Sjogren’s disease (sicca, xerostomia), (epi)scleritis

• Pulmonary: RA-ILD (UIP most common, Caplan Syndrome if silica inhalation), asymptomatic pleural thickening & small effusions, nodules → cavitation, airway disease (bronchiectasis, bronchiolitis)

• Cardiac: pericarditis, myocarditis, nodular infiltration

• Hematologic: Felty syndrome (neutropenia + splenomegaly)*, LGL leukemia

• Rheumatoid vasculitis*: cutaneous (retiform purpura, nail fold infarcts, & ulcers) > mononeuritis multiplex, myositis

📚 The risk of extraarticular disease ↑ if disease is seropositive, if patient is male, & if patient smokes

📚 Rheumatoid vasculitis is exceedingly rare (< 1%) & often seen 10+ years after Dx

*Manifestations usually require longstanding, untreated, severe disease