Circulating DNA in polyarteritis nodosa and related syndromes

Patients with systemic lupus erythematosus (SLE) were previously reported to have a high prevalence of circulating DNA in association with systemic vasculitis. The present study was designed to determine whether circulating DNA also characterizes forms of systemic arterial inflammation other than those associated with SLE. A specific counterimmunoelectrophoresis assay capable of detecting 20-50 ng/ml of double-stranded DNA (dsDNA) in plasma was used. Of a total of 16 patients studied, 15 (94%) had circulating DNA. Similarly, 89% of the 47 plasmas from vasculitis patients contained DNA. In each of the 3 control groups, which consisted of normal individuals, patients with nonvasculitic systemic inflammation, and patients receiving high dose corticosteroid and/or cytostatic agents, no more than 8% had plasma DNA. This difference was significant with P less than 0.001. Relevance of this observation to etiologic, pathogenetic, and clinical considerations in the systemic arteritides is discussed. It is suggested that clinical detection of circulating plasma DNA may be useful for the diagnosis and management of systemic polyarteritis nodosa and related syndromes.