Abstract-Text (inkl. Referenzen und Bildunterschriften)

Introduction: Autoimmune encephalitis associated with antibody against GABA-B varies in its clinical presentation. The disease is difficult to distinguish from some other conditions without testing for anti-GABA-B antibody in blood serum or cerebrospinal fluid. Cerebral lesions are typically detected by magnetic resonance imaging (MRI) in the medial temporal lobe or hippocampus. Clinical case: A 65-year-old man reported memory loss, convulsions, and disturbed consciousness before presentation in the emergency room. The left upper arm showed reduced autonomous movement after painful stimuli, and MRI showed abnormal hyperintensities in the left frontal lobe on T2 and fluid-attenuated inversion recovery sequences, restricted diffusion, and decreased cerebral blood flow. Contrast-enhanced T1-weighted MRI showed gyral enhancement involving the cortex and subcortical white matter. Computed tomography angiography did not identify culprit blood vessels. Screening for serum antibodies associated with autoimmune encephalitis detected antibody against GABA-B. A corticosteroid therapy, intravenous immunoglobulin therapy and plasmapherese doesn"t really improved symptoms. In this particular case, the patient did not have any type of cancer. However, subsequent analyses and diagnostics revealed the suspicion of a lung tumour, which, due to the patient's death, could not be confirmed. Conclusion: Today, the detection of autoantibodies against nerve or glial cells enables the early and specific diagnosis of autoimmune encephalitis in numerous neurological and psychiatric symptom complexes. This has also fundamentally changed the approach to immunotherapeutic treatment of this group of diseases, as well as the understanding of the underlying pathophysiology and triggering factors. The still growing number of new autoantibodies requires a regular update on the state of antibody diagnostics, the frequency of associated tumours as well as the antibody-specific spectrum of clinical symptoms, ranging from personality changes and cognitive disorders to epileptic seizures and movement disorders as well as vegetative and consciousness disorders. In a large proportion of patients, immunotherapy or tumor therapy can lead to a substantial or complete improvement of symptoms. In addition, there are allosteric agonists of the GABA-B2 subunit, which can block the antibody-blocked GABA-B1 subunit and thus represent a potential therapeutic option.