[Dementia as a primary symptom in late onset multiple sclerosis. Case series and review of the literature].

Cognitive impairment is meanwhile accepted as a well-known symptomatology affecting up to 60% of the patients even in the early disease course of multiple sclerosis (MS). After a longer duration the development of dementia is not unusual. However, cognitive dysfunction as the primary or only manifestation of MS is thought to be rare. We report on four elderly patients referred to the memory clinic of our psychiatric university hospital because of beginning dementia. All of them were found to have evidence of a chronic inflammatory CNS process compatible with the diagnosis of MS. At the beginning of their symptomatology all patients were older than 60 years . Just in one case, progressive gait disturbances beginning after cognitive decline contributed to restriction in the activities of daily living. Data of 239 cases of the literature were reviewed and revealed motor disturbances as the main initial symptom and often a primary progressive course with unfavourable prognosis in late onset MS. Until now dementia as the primary symptomatology has not been described in patients older than 60 years. Possibly MS as a differential diagnosis in dementia as well as cognitive impairment as an initial symptom of MS is under-recognized.