Autoimmune Encephalitis: Current Knowledge on Subtypes, Disease Mechanisms and Treatment

Abstract

<jats:sec> <jats:title>:</jats:title> <jats:p>Autoimmune encephalitides (AE) comprises a group of diseases with antibodies against neuronal synaptic and cell surface antigens. Since the discovery of the most common subtype, N-Methyl-D-Aspartate (NMDA) receptor encephalitis, an astonishing number of novel disease-causing antibodies have been described. This includes other glutamatergic and GABAergic receptor antibodies and antibodies against various other surface proteins. Many of these novel conditions present as limbic encephalitis with memory impairment, psychiatric features and epileptic seizures, often alongside subtype specific clinical features. Others present with a clinical disease course specific to the antibody. In contrast to the well-known paraneoplastic syndromes with antibodies directed against intracellular antigens (e.g. limbic encephalitis with Hu antibodies), autoimmune encephalitides are often highly responsive to immunotherapy, with a good outcome if diagnosed and treated early. Prognosis depends on aggressive immunotherapy, often with a combination of corticosteroids, intravenous immunoglobulin, plasma exchange or in some cases anti-CD20 therapy and cyclophosphamide. Other treatment regimens exist, and prognosis vary between disease subtypes and occurrence of underlying cancer. We review the current knowledge on subtype-specific clinical presentation, proposed disease mechanisms, diagnosis including pitfalls, treatment paradigms and outcome in autoimmune encephalitides, and provide suggestions for future research in treatment. </jats:p> </jats:sec>

Rapidly progressive cognitive decline associated with teprotumumab in thyroid eye disease

“…Nevertheless, the presence of high protein level in the cerebrospinal fluid, as well as rapid improvement of symptoms with plasmapheresis, indicated a possible immunologic cause supporting the diagnosis of autoimmune encephalitis syndrome. 2 Although this disorder is more commonly associated with antibodies to neuronal cell surfaces/synaptic proteins and paraneoplastic syndromes, it has been reported to occur in the absence of cancer. Our patient had no known underlying malignancy.…”

“…Therapeutic plasmapheresis is currently used to treat neurological disorders such as Guillain-Barre syndrome, myasthenia gravis, chronic inflammatory demyelinating polyneuropathy and autoimmune encephalitis. 2 5 It is possible that plasmapheresis was effective in removing teprotumumab-induced antibodies to neuronal surfaces and synaptic proteins, resulting in neurological improvement. It would have been interesting to analyse and characterise the substances removed by apheresis; however, this was not done in our patient.…”

Research progress in teratoma‐associated anti‐N‐methyl‐D‐aspartate receptor encephalitis: The gynecological perspective

“…Likewise adult symptoms may vary by gender; overall, psychiatric and behavioral symptoms may be present in more than 80% of adult patients, and these symptoms are most significant in 54% of male patients and 67% of female patients. 32 Although most patients with anti-NMDAR encephalitis start with prodromal symptoms, previous studies have described a purely psychotic form of illness resembling schizophrenia, and the presence of acute psychotic symptoms or unexplained behavioral problems in young female patients may be the only first symptom of this rare teratoma causing anti-NMDAR encephalitis. 33 As most patients are initially treated for infectious causes, neuropsychiatric sequelae become a potentially important issue.…”

“…The EEG of up to 96% of patients with anti-NMDAR encephalitis can show nonspecific widespread diffuse slowing with epileptic focal activity, and in 13%-58% of these cases the EEG can show a delta brush, a delta wave background with a specific frequency of beta waves superimposed, which is neither sensitive nor specific for anti-NMDAR encephalitis, although it is a unique EEG pattern. 32,34 Imaging On magnetic resonance imaging (MRI) images of the brain, abnormalities are preferentially seen in fluidattenuated inversion recovery sequences, including high signal in the bilateral temporal lobe, frontal lobe, subcortical white matter, and periventricular regions; they may also show contrast enhancement in the soft meninges and cortex. Although the majority of anti-NMDAR encephalitis patients with abnormalities on cranial computed tomography (CT) or MRI are usually nonspecific, imaging is significant in screening for ovarian teratomas.…”

Current Perspectives on Neurological Diseases: Experimental Models, Mechanisms of Disease and Treatments

“…Scheller Nissen et al [5] in depth describe the current knowledge, disease mechanisms, diagnosis and treatment of Autoimmune Encephalitides (AE). AE comprise an astounding number of diseases characterized by antibodies against neuronal synaptic and cell surface antigens.…”