[Low complement levels in urticarial vasculitis as first manifestation of systemic lupus erythematosus].

Hypocomplementaemic urticarial vasculitis syndrome is a leukocytoclastic vasculitis characterized by urticarial lesions, associated with fever, arthralgias, arthritis and abdominal pain. Other systemic manifestations include glomerulonephritis, uveitis, episcleritis, chronic obstructive pulmonary disease and neurological abnormalities. Some case associated with systemic lupus erythematosus have been described and SLE diagnosis was made by previous or concomitant diagnostic criteria before onset of urticarial vasculitis. Urticarial vasculitis prior to SLE diagnosis is rare. The development of anti-Ro/SS-A antibody for the diagnosis of SLE is emphasized. The authors alert to the importance of periodically searching for this marker in patients with urticarial vasculitis.