Therapy for granulomatous angiitis.

The clinical diagnosis of granulomatous angiitis can be extremely difficult because of the diversity of presentation. A clinical presentation of progressive multifocal encephalopathy is most common but signs suggesting isolated mass lesions or dementia may be seen. Laboratory studies are helpful, particularly when CSF examination reveals elevated protein or a mononuclear cell response. Cerebral angiogram may demonstrate vasculitis but tissue biopsy is extremely important in firmly establishing a diagnosis. Leptomeningeal biopsy should be performed before initiation of appropriate immunosuppressive therapy and before major irreversible loss of neurologic function occurs. Corticosteroid therapy is the initial treatment of choice, although recent anecdotal reports suggest additional benefits of immunosuppressive drugs such as cytoxan in refractory cases. Whether immunosuppressive drugs should be added routinely cannot be ascertained at present. However, in view of the likelihood of an extended period of treatment, and perhaps relapses when treatment is discontinued, the need to establish an unequivocal diagnosis is of utmost importance when treating with potentially hazardous drugs.