Humans ; Anti-N-Methyl-D-Aspartate Receptor Encephalitis/therapy* ; Child ; Receptors, N-Methyl-D-Aspartate/immunology* ; Prognosis ; Immunotherapy/methods* ; Autoantibodies/blood*

Adult ; Female ; Humans ; Limbic Encephalitis ; etiology ; Ovarian Neoplasms ; complications ; Paraneoplastic Syndromes, Nervous System ; etiology ; Receptors, N-Methyl-D-Aspartate ; immunology ; Seizures ; etiology ; Teratoma ; complications

BACKGROUNDAutoimmune encephalitis associated with antibodies against γ-aminobutyric acid B receptor (GABA B R) in patients with limbic encephalitis (LE) was first described in 2010. We present a series of Han Chinese patients for further clinical refinement.

METHODSSerum and cerebrospinal fluid (CSF) samples from patients referred to the program of encephalitis and paraneoplastic syndrome of Peking Union Medical College Hospital were tested with indirect immunofluorescence. Clinical information of patients with anti-GABA B R antibody positivity was retrospectively reviewed, and descriptive statistical analysis was performed.

RESULTSAll eighteen anti-GABA B R antibody-positive cases had limbic syndromes, and electroencephalogram (EEG) or neuroimaging evidence fulfilled the diagnostic criteria of LE. Four patients had additional antibodies against Hu in serum and one had anti-N-methyl-d-aspartate receptor antibody in both sera and CSF. Seventeen (17/18) patients presented with new-onset refractory seizure or status epileptics. Twelve (12/18) patients had memory deficits, 11 (11/18) patients had personality change, 7 (7/18) patients had disturbance of consciousness, and 3 (3/18) patients showed cerebellar dysfunction. One patient with LE had progressive motor and sensory polyneuropathy. Lung cancer was detected in 6 (6/18) patients. Ten (10/18) patients showed abnormality in bilateral or unilateral mediotemporal region on magnetic resonance imaging. Ten (10/18) patients had temporal lobe epileptic activity with or without general slowing on EEG. Seventeen patients received immunotherapy and 15 of them showed neurological improvement. Four patients with lung cancer died within 1-12 months due to neoplastic complications.

CONCLUSIONSOur study demonstrates that most Han Chinese patients with anti-GABA B R antibody-associated LE have prominent refractory epilepsy and show neurological improvement on immunotherapy. Patients with underlying lung tumor have a relatively poor prognosis. Testing for anti-GABA B R antibodies is necessary for patients with possible LE or new-onset epilepsy with unknown etiology.

Adult ; Autoantibodies ; immunology ; China ; Electroencephalography ; Epilepsy ; immunology ; pathology ; Female ; Humans ; Limbic Encephalitis ; immunology ; pathology ; Male ; Middle Aged ; Receptors, N-Methyl-D-Aspartate ; immunology ; Retrospective Studies ; gamma-Aminobutyric Acid ; metabolism

Autoimmune Diseases ; diagnosis ; etiology ; therapy ; Child, Preschool ; Encephalitis ; diagnosis ; etiology ; therapy ; Female ; Humans ; Receptors, N-Methyl-D-Aspartate ; immunology

Autoimmune encephalitis is rare and has various clinical manifestations, which may hamper the correct diagnosis. Therefore, the pediatrician should be familiar with the clinical symptoms, signs, laboratory features, neuroimaging changes, immunological characteristics, and differential diagnosis of this disease. In order to correctly diagnose anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis, cerebrospinal fluid (CSF) examinations including detection of oligoclonal bands, brain MRI scanning, and routine EEG and/or 24 hours video EEG should be performed in children. For highly suspected cases, particularly children presenting with psychiatric symptoms and epileptic seizures, examinations should be done to detect anti-NMDAR antibodies (Abs) in serum and CSF. A notable feature in children is the EEG pattern named "extreme delta brush", which may help confirm the clinical diagnosis. Anti-NMDAR Abs in CSF is the diagnostic "gold-standard" for this disease. The differential diagnosis of anti-NMDAR encephalitis is broad. In pediatric patients, the differential diagnosis should be made mainly with herpes simplex virus encephalitis, other autoimmune encephalitis, and psychosis.
Anti-N-Methyl-D-Aspartate Receptor Encephalitis ; diagnosis ; Antibodies ; analysis ; Diagnosis, Differential ; Electroencephalography ; Humans ; Magnetic Resonance Imaging ; Receptors, N-Methyl-D-Aspartate ; immunology

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is the most prevalent type of encephalitis. Investigating the pathogenesis of anti-NMDAR encephalitis will enhance our understanding of this disease and play a central part in providing reasonable treatment for the patients. The pathogenesis is elucidated as follows: (1) the findings of the relationship between anti-NMDAR encephalitis and tumors; (2) further research on the relationship between anti-NMDAR encephalitis and tumors; (3) NMDAR epitopes and the autoimmunity of patients; (4) the interaction between antibody and NMDAR; (5) the pathogenesis of anti-NMDAR encephalitis without tumors. This review gives a brief introduction to the methodology and way of finding out the valuable clinical problems and making a clear and explicit explanation of them by exhibiting the process of discovering the disease, disclosing its relationship with tumors, and investigating its pathological and molecular mechanism. Current studies have demonstrated that anti-NMDAR encephalitis is an autoimmune disease of the nervous system that is closely associated with tumors, particularly ovarian teratoma.
Anti-N-Methyl-D-Aspartate Receptor Encephalitis ; etiology ; Antibodies ; immunology ; Autoimmunity ; Humans ; Neoplasms ; complications ; Receptors, N-Methyl-D-Aspartate ; immunology

OBJECTIVETo study the clinical and laboratory features and diagnosis of the patient with anti-N-methyl-D-aspartate receptor(NMDAR)encephalitis in children.

METHODThe data of clinical feature, laboratory findings, and radiological manifestation were reviewed and analyzed.

RESULTOf the 7 patients, 4 were female and 3 were male. The age of onset was from 6.6 to 15.5 years (average 9.5 years). The onset of 4 cases started with convulsion. Six cases had seizures which was difficult to control by antiepileptic drugs. All patients had psychiatric symptoms and speech disorder. Six cases had different levels of decreased consciousness and dyskinesias. 6 cases had autonomic nerve instability, and 7 cases developed sleep disorders. The results of MRI examination were normal in all patients. The EEG of most patients showed focal or diffuse slow waves. Six cases had oligoclonal bands. All cases were confirmed to have the disease by detection of anti-NMDA receptor antibodies. No tumor was detected in any of the patients. All patients received immunotherapy.

CONCLUSIONAnti-NMDAR encephalitis is a severe but treatable disorder that frequently affects children and adolescents. Pediatric patients had clinical manifestations similar to those of adult patients. But children have a lower incidence of tumors and hypoventilation also occurs less frequently in children. Most of children had a good prognosis.

Adolescent ; Anti-N-Methyl-D-Aspartate Receptor Encephalitis ; complications ; diagnosis ; therapy ; Autoantibodies ; blood ; cerebrospinal fluid ; Autonomic Nervous System ; physiopathology ; Brain ; diagnostic imaging ; pathology ; Child ; Electroencephalography ; Female ; Humans ; Immunotherapy ; methods ; Magnetic Resonance Imaging ; Male ; Movement Disorders ; etiology ; Radiography ; Receptors, N-Methyl-D-Aspartate ; immunology ; Retrospective Studies ; Seizures ; etiology

BACKGROUNDNR2B containing N-methyl-D-aspartate (NMDA) receptor plays an important role in the facilitation and maintenance of neuropathic pain. The discrete distribution of NR2B subunit in the central nervous system (CNS) may support reduced side effects of agents that act selectively at this site. Therefore, we investigated the hypothesis that a humoral autoimmune response targeting the NR2B subunit of NMDA receptor relieves pain like behaviours produced by peripheral injury.

METHODSRats were immunized subcutaneously with NR2B-Keyhole Limpet Hemocyanin (NR2B-KLH) three times at two-week intervals. NR2B specific IgG titres in sera and cerebrospinal fluid were determined by indirect ELISA. Seven days after the third immunization, 2 of the 3 terminal branches of the sciatic nerve (tibial and common peroneal nerves) were tightly ligated. Behavioural testing was carried out on every other day after surgery, until 7 days after surgery. The lumbar spinal cord (L4-6) was removed on day 7 after ligation. The expression of NR2B protein in the lumbar spinal cord was determined using Western blotting.

RESULTSAfter the second vaccination, NR2B specific IgG in sera was detected to be > 0.5 microg/ml in six of nine rats. After the third vaccination, all the immunized rats had > 2.2 microg/ml. Titres of NR2B specific IgG in sera peaked 42 days post initial immunization and persisted for over 70 days. No NR2B specific IgG was detected in sera from PBS or KLH group. The behavioural thresholds in NR2B group were significantly higher than those in PBS and KLH groups on day 7 after ligation. NR2B specific IgG in CSF in NR2B group could not be detected on day 1 before spinal dissection; but could be detected on day 7 after surgery. The expression of NR2B protein in group NR2B was significantly lower than in PBS and KLH groups on day 7 after surgery.

CONCLUSIONThe NR2B peptide could be used as a vaccine against neuropathic pain, which could be associated with reduction of NR2B protein in the lumbar spinal cord.

Adjuvants, Immunologic ; Animals ; Blotting, Western ; Disease Models, Animal ; Enzyme-Linked Immunosorbent Assay ; Female ; Hemocyanins ; immunology ; Immunoglobulin G ; immunology ; Neuralgia ; immunology ; physiopathology ; prevention & control ; Pain Measurement ; Rats ; Rats, Sprague-Dawley ; Receptors, N-Methyl-D-Aspartate ; immunology ; metabolism ; Recombinant Fusion Proteins ; administration & dosage ; immunology ; Spinal Cord ; drug effects ; metabolism ; physiopathology ; Time Factors ; Vaccines ; administration & dosage ; immunology