Parkinsonism and multiple sclerosis--is there association?

Association between multiple sclerosis (MS) and parkinsonism is rarely reported. We describe clinical, radiological and DAT scan findings in two patients presenting with parkinsonism. MRI revealed demyelinating lesions of the central nervous system consistent with MS in both patients. On the other hand, DAT scan findings were supportive of Parkinson's disease. There is still an open debate whether MS lesions can cause parkinsonism, or these are just coincidental findings of two different diseases in the same patient. Although there are cases of causal relationship between parkinsonism and MS, some literature reports and our observations suggest that Parkinson's disease and MS can coexist as two separate diseases in the same patient. It is possible that the symptoms of Parkinson's disease can be aggravated by MS plaques, explaining the favorable response to corticosteroids in some patients.