ABSTRACT
The case illustrates that mediotemporal lobe epilepsy with hippocampal sclerosis may rarely present as an adult-onset disease on the basis of chronic limbic encephalitis. Limbic encephalitis is usually associated with a neoplasia and is then known as paraneoplastic limbic encephalitis. However, cases without neoplasia have been identified in a cohort of patients undergoing presurgical evaluation (non-paraneoplastic limbic encephalitis). Limbic encephalitis should be included in the differential diagnosis of temporal lobe epilepsy that is not typical for the
MRI scan. A malignant condition, usually a small cell lung cancer in the presence of characteristic autoantibodies, needs to be excluded. Long-term follow-up in cases of suspected paraneoplastic limbic encephalitis is mandatory because the neurological syndrome may begin more than 2 years before the detection of the underlying tumor.
