Case Report: Autoimmune Encephalitis Associated with GABA-B Antibody Mimicking Cerebral Infarction
José Padrao Mendes1* and Gabriele Woebker2
1 Helios Universitätsklinikum Wuppertal, Germany.
2 Helios Universitätsklinikum Wuppertal, Germany.
*Corresponding Author: José Padrao Mendes, Helios Universitätsklinikum Wuppertal, Germany.
DOI: https://doi.org/10.58624/SVOANE.2024.05.0159
Received: November 11, 2024 Published: December 06, 2024
Abstract
Autoimmune encephalitis associated with GABA-B antibodies varies in its clinical presentation. Without testing for anti-GABA-B antibodies in blood serum or cerebrospinal fluid, the disease is difficult to distinguish from some other conditions. Cerebral lesions are typically detected by magnetic resonance imaging (MRI) in the medial temporal lobe or hippocampus. We describe a patient with an autoimmune encephalitis caused by anti-GABA-B antibodies who presented with an initial focal epilepsy. The 65-year-old man reported memory loss, seizures, and altered consciousness prior to presentation to the emergency department (ED). The left arm showed reduced autonomous movement to 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 autoimmune encephalitis-related serum antibodies revealed anti-GABA-B antibodies. A course of corticosteroids, intravenous immunoglobulin therapy and plasmapheresis didn't really improve the symptoms. In this particular case, the patient had no cancer. However, subsequent analysis and diagnosis raised the suspicion of a lung tumour. However, this could not be confirmed due to the patient's death. The early and specific diagnosis of autoimmune encephalitis in many neurological and psychiatric symptom complexes is now possible through the detection of autoantibodies against nerve or glial cells. This has 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, movement disorders, vegetative and consciousness disorders.
Keywords: Autoimmune Encephalitis, GABA-B, GABA-B Receptor, Encephalitis, Antibodies, Diagnostic Criteria, MRI, CSF, Therapy, Outcome
Citation: Mendes JP, Woebker G. Case Report: Autoimmune Encephalitis Associated with GABA-B Antibody Mimicking Cerebral Infarction. SVOA Neurology 2024, 5:6, 262-268. doi. 10.58624/SVOANE.2024.05.0159
