Methods: We report a case of anti NMDA receptor encephalitis in a child with subacute encephalopathy and psychiatric manifestations without malignancy.
Results: Female, 15 years old, healthy, 15 days ago with confusion, behavior and mood disorders, memory loss and agitation worsened progressively and 2 episodes of seizure. On examination: sleepy, confused and disoriented, no segmental deficits or meningeal signs.
Normal serum laboratory tests. Analysis of cerebrospinal fluid (CSF) showed an increase of leukocytes (41/mm3) with a predominance of lymphocytes (98%); immunology negative for syphilis and cysticercosis in CSF. Search oligoclonal bands: normal IgG in serum and CSF. Normal magnetic resonance imaging of skull. Electroencephalogram disorganization and diffuse slowing of brain electrical activity.
after another seizure, the patient had a decreased level of consciousness, speech impairment, movement disorders and muscle clonus, without motor response to stimuli (Glasgow 6). Received corticosteroid pulse therapy with 1 g / day for 3 days, human immunoglobulin 40 mg / day intravenously for 3 days and 6 sessions of plasmapheresis with mild clinical improvement.
After the detection of anti NMDA receptor antibody, began treatment with rituximab with good evolution. Showed no hemodynamic instability and no malignancies were found. At discharge, kept rituximab every 3 weeks and anticonvulsants. After 20 months of diagnosis, showed no change in behavior, motor or cognitive.
Conclusions: Anti NMDA receptor encephalitis is a rare disease. Up until 2012, only 3 cases of the disease were reported in Brazil. Often confused with psychiatric disorders or infectious encephalitis is still underdiagnosed and should always be considered. A retrospective study of adults with unknown etiology encephalitis demonstrated anti NMDA receptor antibodies in 1% of patients admitted to an intensive care unit.