An unusual case of acute psychosis in an adolescent

Anti-N-methyl-D-aspartate receptor (NMDA-R) encephalitis is a severe form of encephalitis that has been identified within the context of acute neuropsychiatric manifestations. We report the case of an 18-year-old adolescent referred for a first episode of acute psychosis. The clinical picture rapidly deteriorated to a state of catatonia, decreased consciousness and autonomic instability. Detection of highly positive anti-NMDA-R antibodies confirmed the diagnosis of anti-NMDA-R encephalitis. Immunosuppressive treatment and repeated plasma exchange resulted in slow recovery. The literature on diagnosis and treatment of this specific type of encephalitis is reviewed.

Ophthalmoplegia and flaccid paraplegia in a patient with anti-NMDA receptor encephalitis: a case report and literature review

We herein report the case of a 26-year-old woman with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis presenting with ophthalmoplegia and flaccid paraplegia. She developed disorientation and hallucination after fever and vomiting. Hypothermia, hypoventilation, hypertension, paralytic ileus and hyponatremia were present. Neurological examination showed mild consciousness disturbance and bilateral ophthalmoplegia on admission, flaccid paraplegia with leg areflexia on Day 4. Anti-NMDAR antibodies were detected in the serum and cerebrospinal fluid samples. Motor nerve conduction velocity was decreased in the tibial and peroneal nerves. F-wave amplitudes were reduced in the tibial nerve. MRI disclosed lesions in the callosal splenium, hippocampus and cerebral subarachnoid regions. In addition to various encephalitic symptoms, physicians should pay more attention to peripheral nerve damage in patients with anti-NMDAR encephalitis.

Immune-mediated pediatric epilepsies

Apart from Rasmussen encephalitis, other immune-mediated brain disorders have emerged that are frequently associated with recurrent epileptic seizures: (1) limbic encephalitis, (2) anti-N-methyl-D-aspartate-receptor (NMDAR) encephalitis, and (3) steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT, formerly called Hashimoto encephalopathy). Limbic encephalitis mainly affects the mediotemporal aspect of the cortex giving rise to temporal lobe seizures and memory and affective disturbances. It can occur as a paraneoplastic or, even more frequently, a nonparaneoplastic condition. Detection of specific autoantibodies may suggest underlying cancer (onconeural antibodies) and may give hints regarding the long-term prognosis. VGKC-complex or GAD antibodies have been identified in children. Anti-NMDAR encephalitis is a disorder mainly of female adolescents and young adults. Patients present with seizures in around one-third of cases, and 80% of patients develop recurrent, mainly extratemporal seizures at some stage of their disorder. The clinical course is that of a mostly monophasic, but sometimes multiphasic, severe cortico-subcortical encephalopathy. Ovarian teratomas underlie the disorder in 30-60% of adult cases but are rare in young children. Tumor removal and early intense immunotherapy are predictors for a favorable outcome. SREAT is not a disorder with definite pathogenesis but rather a "catch all" for encephalopathic immune-mediated brain diseases (often with seizures) which have in common thyroid antibodies and a good response to steroid therapy.

[Anti-N-methyl-D-aspartate receptor encephalitis in seven children]

OBJECTIVE

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

METHOD

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

RESULT

Of 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.

CONCLUSION

Anti-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.

[Autoimmune synaptic encephalitis]

Autoimmune synaptic encephalitis (ASE) is a recently recognized disease entity. The early and correct diagnosis of ASE is of importance, since the prognosis depends on the early onset of treatment. We present two Danish case reports of ASE: a 15-year-old boy presenting with a severe course of N-methyl-D-aspartate-encephalitis including persistent cognitive deficits, and a 59-year-old woman with coeliac disease presenting with leucine-rich glioma inactivated 1-encephalitis including dyskinesia, epilepsy, psychiatric features and vocal tics.

[Fast and spectacular clinical response to plasmapheresis in a paediatric case of anti-NMDA encephalitis]

INTRODUCTION

Autoimmune encephalitis against N-methyl-D-aspartate (NMDA) receptors is being diagnosed more and more frequently in the paediatric age. It should be suspected in children with psychiatric symptoms, encephalopathy, abnormal movements or epileptic seizures. Paraneoplastic cases are less frequent than in adults.

CASE REPORT

We report the case of a boy, 2.5 years of age, with subacute encephalopathic signs and symptoms and epileptic seizures followed by behaviour disorders, neurological regression, dyskinesias and insomnia. Results of a cerebrospinal fluid study were normal, the magnetic resonance scan of the head revealed a focal periventricular lesion and diffuse leptomeningeal uptake; moreover, the serial electroencephalograms showed high-amplitude delta activity interspersed with generalised intercritical epileptiform activity. The patient was given empirical treatment with high doses of corticoids and intravenous immunoglobulins with no response. After showing up positive for antibodies against the NMDA receptor, plasmapheresis was begun, which led to his swift and spectacular recovery. After more than 18 months' follow-up, his sequelae are limited to mild behavioural and language alterations. He has had no relapses and has not needed any kind of maintenance treatment.

CONCLUSIONS

Anti-NMDA encephalitis is a treatable disorder and, sometimes, the first evidence of an underlying neoplasia, which makes its early recognition and treatment essential. Treatment of the non-paraneoplastic forms are based on immunotherapy: glucocorticoids, intravenous immunoglobulins, plasmapheresis and immunosuppressants. Plasmapheresis can bring about a fast, spectacular improvement.

Anti-NMDA receptor encephalitis with the initial presentation of psychotic mania

We report a 16-year-old girl with suspected psychotic mania, who subsequently developed amnesia, catatonia, oro-lingual dyskinesia, consciousness disturbance, seizure and respiratory failure. Repeated studies of the cerebrospinal fluid (CSF), viral culture and serology, brain MRI, single photon emission CT scan, and autoimmune profiles were all normal. She was finally diagnosed with anti-N-methyl D-aspartate receptor (NMDAR) encephalitis based on the positive finding of NMDAR antibodies in CSF. Her abdominal CT scan showed no detectable malignancy and pulse steroid therapy failed to have any effect. After administration of intravenous immunoglobulin her consciousness improved gradually. Anti-NMDAR encephalitis, with a characteristic neuropsychiatric syndrome, predominantly affects females with an ovarian tumor and is frequently misdiagnosed as a psychiatric disorder. Immunotherapy and eradication of associated malignancy are the main treatment strategies. Early recognition and early intervention of the disease should improve the outcome.

Central neurogenic hyperventilation in anti-NMDA receptor encephalitis

Central neurogenic hyperventilation (CNH) is a rare condition that is generally associated with infiltrative tumors of the brainstem. Respiratory dysfunction, particularly central hypoventilation, is common in anti-N-methyl D-aspartate (NMDA) receptor encephalitis. CNH, to the best of our knowledge, has not been described previously in this disease. A 24-year-old woman was diagnosed with anti-NMDA receptor encephalitis secondary to ovarian teratoma. In addition to the typical symptoms of the disease, recurrent CNH episodes were observed during the course of the illness, which subsided with midazolam and propofol infusion. Supportive and disease-specific treatments, including oopherectomy, plasmapheresis and intravenous immunoglobulin, provided excellent recovery. These observations suggest that NMDA receptors may play a role in the pathophysiology of CNH.