[Wegener's granulomatosis and microscopic polyangiitis].
Wegener's granulomatosis and microscopic polyangiitis are among the main systemic necrotizing vasculitides predominantly affecting small vessels. Their prevalences range from 24 to 157 cases per million inhabitants. Mean age at onset is usually 40 to 60 years old. Most common and suggestive features of Wegener's granulomatosis are upper (sinusitis, crusting rhinitis, saddle nose deformity, otitis media) and lower (excavated lung nodules, alveolar hemorrhage) respiratory tract, and kidney involvements. Alveolar hemorrhage and crescentic necrotizing glomerulonephritis are also characteristic manifestations of microscopic polyangiitis. Mononeuritis multiplex and necrotic purpura are frequent symptoms in both diseases. Antineutrophil cytoplasm autoantibodies (ANCA) directed against proteinase 3 can be found in the serum of 90% of the patients with diffuse forms of Wegener's granulomatosis, whereas ANCA with anti-myeloperoxidase specificity, whose pathogenic role is now well documented, can be detected in more than 60% of those with microscopic polyangiitis. Histologically, Wegener's granulomatosis can be differentiated from its counterpart when the inflammatory infiltrates have a granulomatous pattern. Therapy relies on the combination of corticosteroids and pulse intravenous cyclophosphamide, which can be switched, as soon as remission is achieved, to azathioprine or methotrexate, for a total duration of treatment of at least 18 months. Ten-year survival rate now exceeds 80%, but relapses are frequent. The precise place of new biologics, such as rituximab, needs to be further defined.
Pagnoux
Christian
C
Centre de référence maladies auto-immunes et maladies systémiques rares, vascularites nécrosantes et sclérodermie systémique, pôle de médecine, hôpital Cochin, Université Paris-5, Paris. christian.pagnoux@cch.aphp.fr
D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000627:therapeutic use; D000328:Adult; D000367:Age Factors; D000368:Aged; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000276:immunology; D001379:Azathioprine / Q000008:administration & dosage / Q000627:therapeutic use; D002648:Child; D003520:Cyclophosphamide / Q000008:administration & dosage / Q000627:therapeutic use; D003937:Diagnosis, Differential; D004359:Drug Therapy, Combination; D005260:Female; D014890:Granulomatosis with Polyangiitis / Q000145:classification / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology / Q000276:immunology / Q000401:mortality / Q000503:physiopathology; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D013902:Radiography, Thoracic; D012008:Recurrence; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014657:Vasculitis / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology / Q000276:immunology / Q000401:mortality / Q000503:physiopathology
D000305:Adrenal Cortex Hormones; D019268:Antibodies, Antineutrophil Cytoplasmic; D007166:Immunosuppressive Agents; D003520:Cyclophosphamide; D001379:Azathioprine