[dwerten]

Radiation therapy has been used to treat GME of dogs in the past.8 However, it was not always effective in dogs that relapsed when prednisone therapy was discontinued.8 With the advent of therapies such as lomustine and cyclosporine there is little indication to use radiation therapy to treat autoimmune CNS disease of dogs since these chemotherapeutic agents seem to be more effective.

Summary: Prednisone alone, in immunosuppressive doses, tapered slowly over 6 months, is often effective in causing permanent remission of neutrophilic and eosinophilic meningitis or focal brainstem or forebrain GME. If these conditions relapse when prednisone therapy is reduced or discontinued, then other chemotherapeutic agents such as lomustine (used for 1 year) and/or microemulsion cyclosporine (used for 1.5 years) can be added to achieve permanent remission. Dogs with GME involving the spinal cord or visual pathways or that have necrotizing encephalitis should be treated with combination therapy of prednisone, lomustine, cytarabine and cyclosporine modified from the outset if they are to survive long-term. Leflunomide therapy can also be used to treat resistant cases that relapse despite combination therapy with other drugs.


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