Dystonia is a broad range of movement disorders. Dopa-responsive dystonia is one category that is very similar to Parkinsonism. This is what my son is diagnosed with. The main difference, from what I understand, is that dopa-responsive dystonia is generally progressive to a point and then levels off. Parkinsonism is a continually progressive, degenerative disease. Both are treated with the same medication. It's the prognosis that differs.