Limbic encephalitis: clinic, pathogenesis and diagnostic problems

Abstract

Limbic encephalitis is a rare and potentially serious disease, which may or may not be paraneoplastic and is characterized by recent memory deficits, psychiatric disturbances and seizures. Of autoimmune origin, it is associated with serum and intrathecal antibodies against intracellular and surface neuronal antigens, with special involvement of limbic areas.

This article reviews historical and epidemiological aspects, pathogenesis, more frequent and better defined syndromes, histopathology and complementary studies. The difficulties of differential diagnosis and the need to always rule out an underlying tumor are also reviewed.

Detection of neuronal autoantibodies is important for diagnosis, therapeutic planning and prognosis. Immunotherapy and, if appropriate, neo- plasm treatment, are crucial to achieve substantial neurological recovery.

Limbic encephalitis is probably an underdiagnosed entity, with a more favorable prognosis if treated early. The current knowledge of its pathogen- esis may also provide clarity for a better understanding of other neurological and psychiatric syndromes that may share autoimmune mechanisms, such as some psychotic disorders and drug-resistant epilepsies.