POLYARTERITIS-NODOSA, MICROSCOPIC POLYANGIITIS, AND CHURG-STRAUSS-SYNDROME

Polyarteritis nodosa (PAN), first described by Kussmaul and Maier, is a well-known form of necrotizing angiitis whose main manifestations ar e weight loss, fever, asthenia, peripheral neuropathy, renal involveme nt, musculoskeletal and cutaneous manifestations, hypertension, gastro intestinal tract involvement, and cardiac failure, Recently individual ized from PAN, microscopic polyangiitis (MPA) is a systemic vasculitis of small-size vessels whose clinical manifestations are very similar to those of PAN, but it is characterized by the presence of rapidly pr ogressive glomerulonephritis (RPGN), which is nearly constant, and pul monary involvement usually absent in PAN, Churg-Strauss syndrome (CSS) is a disorder characterized by hypereosinophilia and systemic necroti zing vasculitis similar to that of PAN and occurring in individuals wi th asthma and allergic rhinitis, Considering the etiologies of PAN, pr imary and secondary vasculitides can also be distinguished because PAN can be the consequence of hepatitis B virus (HBV) infection and somet imes of other etiologic agents. The prognosis of systemic vasculitis h as been transformed by corticosteroids that are, except in HEV-related PAN, the basic treatment, Immunosuppressive drugs, especially cycloph osphamide, have also contributed to improving the prognosis, but their precise role in the management of these vasculitides is still being e lucidated.