Limbic encephalitis
Limbic encephalitis (singular: Limbic encephalitis) are a group of inflammatory diseases of the central nervous system. Characteristic of this occurring mostly in adults and subacute disease are memory impairment, psychiatric disturbances and epileptic seizures.
The term " limbic encephalitis " was coined in the 1960s by British neuropathologist and neurologist, the inflammatory changes were mainly belonging to the limbic system areas in the autopsy of patients.
- 2.1 Diagnostic criteria
- 2.2 CSF
- 4.1 Overview Article
Classification
Limbic encephalitis associated in about 60 percent of cases with cancer. These paraneoplastic limbic encephalitis are then used as (PLE ) refers, of which the limbic encephalitis nichtparaneoplastischen ( NPLE ) can be distinguished. For the non - paraneoplastic limbic encephalitis is either autoimmune diseases or the mechanisms of pathogenesis are not known.
Nichtparaneoplastische limbic encephalitis ( NPLE )
From a NPLE is used when the clinical and imaging criteria for limbic encephalitis are met, but despite extensive tumor search no tumor can be found. The NPLE may be associated with autoantibodies. The antibodies in the NPLE are mostly directed against structures on the surface of nerve cells, while the antibodies in the PLE are mostly directed against intracellular structures. Known antibodies which may be associated with the NPLE are VGKC, NMDA, AMPA, and GAD autoantibodies.
Methods of investigation
Diagnostic criteria
2008 diagnostic criteria were defined as a prerequisite for the diagnosis of limbic encephalitis. A basic prerequisite is the occurrence of limbic syndrome with onset of symptoms less than 5 years. The occurrence of at least one of the following three defined the limbic syndrome: a disorder of Neugedächtnisses, Temporallappenanfälle and / or affective disorder. In addition, in magnetic resonance imaging of the brain temporomediale increased signal intensity in the FLAIR/T2-Wichtung detectable.
The definitive diagnosis of limbic encephalitis can be made according to the criteria, if histologically chronic temporomediale encephalitis is detectable, a tumor was related to the onset of neurological symptoms within 5 years of proven or succeed the detection of well-characterized onkoneuronalen antibodies or antibodies against VGKC.
Where the basic conditions are met, however, does not meet the criteria for a definitive diagnosis, the disease can be classified as a possible limbic encephalitis if MRI Follow-up a volume and shows signal decrease of temporomedialen swelling and signal increase. The increased signal intensity on MRI should not be attributed to a status epilepticus. The signal increase to normal at status epilepticus within a few days.
CSF
The product obtained by a lumbar puncture cerebrospinal fluid ( CSF) has up to 80 % of limbic encephalitis inflammatory changes. Typical is a proliferation of lymphocytes ( lymphocytic pleocytosis ), an increase of the protein, a slight barrier dysfunction, evidence of intrathecal IgG formation and occasionally the detection of oligoclonal bands. The detection antibody antineuronal succeeds both in the cerebrospinal fluid and in serum. The antibody concentration in the cerebrospinal fluid may be significantly higher.
Treatment
Both the paraneoplastic as well as in the non- paraneoplastic limbic encephalitis the beginning of immunotherapy is recommended already at " clinically sufficient suspicion", especially if this is supported by the brain MRI findings. Possible immunotherapies are glucocorticoid therapy with immunoglobulins or conducting a plasmapheresis.
Where the results of tumor and antibodies search before the treatment is adjusted accordingly. So if evidence of a tumor whose treatment is paramount. If proof of a tumor, the result of immunotherapy after 3 months is recommended to check and change if there is no response to another form of immunotherapy. If there is no response after a further 3 months is recommended only continue immunotherapy when there is a VGKC antibody -associated limbic encephalitis.