Plasma exchange in rheumatoid vasculitis.

Plasma exchange (PE) was used to treat 9 patients with rheumatoid vasculitis. The immediate development of new lesions was arrested in 7 patients. Two patients continued to develop new lesions. One responded to additional cyclophosphamide plus methyl prednisolone but the other died within days from severe systemic vasculitis. Prolonged PE alone, or PE followed by cyclophosphamide plus methyl prednisolone was associated with healing of existing lesions without relapse. Short term PE, alone or followed by azathioprine, failed to heal existing lesions and relapses occurred within 3 months. IgG rheumatoid factor and anticomplementary activity fell with PE and correlated best with clinical response.