What should you know about limbic encephalitis?

Abstract

Limbic encephalitis was firstly described by Brierley in 1960 1 and was characterized as an inflammatory disorder involving the hippocampi, amygdala, frontobasal and insular regions, with a spectrum of symptoms, most commonly characterized by a subacute progressive impairment of short-term memory, psychiatric features and seizures. While in some cases it appears to exclusively involve limbic regions, it has become clear that several clinical features implicate involvement of areas other than the limbic system. For this reason, the authors prefer the term autoimmune encephalitis (AIE).Once regarded as a rare and paraneoplastic disorder with a poor prognosis, most forms of AIE are now recognised as being non-paraneoplastic and a substantial proportion of them may have a good response to immunotherapy, particularly if it is promptly initiated.Due to a broad differential diagnosis, the recognition of AIE is frequently difficult and delayed. The aim of this article was to facilitate recognition of the clinical features and to simplify the diagnostic approach, with the ultimate objective of rapid immunotherapy administration. CLINICAL VIGNETTEA 52-year-old, right handed, man presented to the Accident and Emergency (A&E) department after two generalized tonic-clonic seizures. He was previously healthy and was the third of four healthy siblings with no problems during development or birth. He was successful at school and worked as a lawyer. There was no previous history of epilepsy, infections of the central nervous system (CNS), trauma, substance abuse or smoking. He was a moderate consumer of alcohol and was taking no medications. There was no relevant family history. ABSTRACTAutoimmune encephalitis is an inflammatory disorder characterized by a subacute impairment of short-term memory, psychiatric features and seizures. It is often associated with a variety of other neurological symptoms, and its differential diagnosis is wide, leading to challenges in its recognition. It used to be regarded as a rare disease, usually paraneoplastic and with poor prognosis. However, with the recent recognition of membrane-surface directed antibodies, it is now known that in a substantial proportion of cases there is no association with any malignancy and there is a good prognosis if treated. Hence, early recognition and prompt initiation of immunotherapies are of great importance.Key words: limbic autoimmune encephalitis, encephalopathy, intracellular antigens, membrane surface antigens, VGKC-complex, LGI1, CASPR2, N-methylaspartate, paraneoplastic syndrome, immunotherapy. RESUMOA encefalite autoimune é uma doença inflamatória caracterizada por envolvimento subagudo da memória de curto prazo, presença de sintomas psicóticos e crises epilépticas. Dada a diversidade de sintomas na apresentação, o diagnóstico diferencial é um verdadeiro desafio. Anteriormente, era considerada uma doença rara, de etiologia paraneoplásica e com mau prognóstico. No entanto, com a recente descoberta dos anticorpos dirigidos à superfície da membrana, é atua...

Anti-leucine-rich glioma-inactivated 1 limbic encephalitis: A case report and literature review

“…The disorder usually involves the medial temporal area, which causes memory dysfunction and seizures, and has distinctive clinical characteristics, including FBDSs, memory disturbance and a subacute, progressive course (6). According to the literature, hyponatremia is commonly found in patients with anti-LGI1 LE (1); however, this is a non-specific sign (7).…”

Non-paraneoplastic variant of limbic encephalitis – case report

“…neuropathological examination reveals chronically active inflammatory processes in medial temporal lobe and/or the presence of a tumour diagnosed within 5 years of the occurrence of neurological symptoms, and/or the presence of autoantibodies, and/or the signs of inflammation in medial temporal lobe in MRI, which cannot be explained otherwise) [9][10][11]/ Co najmniej jeden objaw z badań morfologicznych (w badaniu neuropatologicznym stwierdzenie przewlekłego zapalenia przyśrodkowej części płata skroniowego i/lub obecność guza zdiagnozowanego w ciągu 5 lat od wystąpienia objawów neurologicznych, i/lub obecność autoprzeciwciał, i/lub w badaniu MRI cechy zapalenia w przyśrodkowej części płata skroniowego, których nie można wyjaśnić inaczej) [9][10][11] the potassium channel (alpha subunit) are rarely detected. Most frequently detected antibodies are those directed against the LGI1 protein, which plays an important role in synaptic transmission as it binds to preand post-synaptic protein complexes [24][25][26][27][28][29], against the CASPR2-associated protein contaktin-2. Limbic encephalitis may have some characteristic medical signs depending on the type of antibodies present.…”

“…Warto zaznaczyć, że u części chorych, u których wykrywa się te przeciwciała, w przebiegu LE również występują nowotwory. Rzadko wykrywa się przeciwciała przeciwko samym białkom tworzącym kanał potasowy (podjednostka a), najczęściej przeciwko białku LGI1, które odgrywa istotną rolę w transmisji synaptycznej poprzez udział w tworzeniu pre-i postsynaptycznych kompleksów białkowych [24][25][26][27][28][29], przeciwko białku związanemu z kontaktyną (CASPR2) i kontaktyną 2 (contaktin-2). Obraz chorobowy LE może mieć pewne charakterystyczne cechy w zależności od rodzaju występują-cych przeciwciał.…”

Autoimmune limbic encephalitis and anesthesia

“…This rare disorder is usually paraneoplastic and is characterized by memory impairment, seizures, psychiatric symptoms, autonomic derangement, involuntary movements, and cognitive dysfunction [1]. It is also usually characterized by the presence of antibodies against various antigens, including those against N-methyl-D-aspartate (NMDA) receptors [1,2]. Therapy consists of immunosuppressants in combination with the management of seizures and psychiatric symptoms.…”