[Treatment of ANCA associated systemic necrotizing vasculitides].

Vasculitides associated with antineutrophil cytoplasmic antibodies (ANCA) mainly affect small vessels. These disorders comprise crescentic glomerulonephritis, Wegener's granulomatosis, microscopic polyangiitis and Churg-Strauss syndrome. Treatment of ANCA-associated vasculitides should be adapted to the type and severity of clinical manifestations, and to certain patient characteristics. Corticosteroids and immunosuppressants are compulsory in Wegener's granulomatosis, but steroids alone can be prescribed to patients with Churg-Strauss syndrome and microscopic polyangiitis without factors of poor prognosis. New biotherapies are showing promise in selected patients but need to be evaluated in the long term. Immunosuppressant and steroid dose reductions, and widespread use of pulse cyclophosphamide instead of oral treatment, have improved patient outcome. Remission is currently obtained in more than 90% of cases but relapses are frequent: for example, more than 50% of Wegener's patients relapse three years after remission. New strategies are needed to prevent relapses and to limit adverse drug effects.