How is the work up PAN?

• - Inflammatory syndrome • - CBC: Hyperleukocytosis, Eosinophilia • - Decrease of CH 50 and fractions, pANCA sometimes positive, negative ANA, latex and Waaler rose negative • - Sometimes positive HBV • - Histo: segmental Vasculitis of medium and small arteries, evolving by relapses, fibrinoid necrosis, granulomas with neutrophils, thrombosis of blood vessels (Lumina). • - Treatment: general corticosteroids. Cyclophosphamide; methotrexate