Based on the own observations, we have summarized the features of symptomatic epilepsy in multiple sclerosis and conducted a clinical analysis of the most diagnostically difficult cases of inflammatory and demyelinating diseases in which epilepsy was the major clinical syndrome. The cases of post-infectious acute disseminated encephalomyelitis, idiopathic cerebral angiitis, Rasmussen's encephalitis are reviewed. Peculiarities of MRI structural brain lesions in these patients are discussed. The use of additional laboratory studies, including a study of cerebrospinal fluid, is considered.