Encefalitis Autoinmune Anti-NMDAR, un reto diagnóstico. Reporte de caso

Abstract

Background: Encephalitis due to antibodies against N-methyl-D-aspartate receptors is an autoimmune disease. However, factors such as herpes simplex virus infection and some neoplasms that trigger the production of these antibodies are required. Nowadays, the etiology of a large percentage of these cases is unknown. The condition presents clinical manifestations that mimic psychiatric disorders, making timely diagnosis and the establishment of adequate therapy difficult, which can limit complications and potential sequelae. Case description: A 17-year-old female patient presented to the health center with depression, easy crying, irritability, and behavioral changes that progressively worsened. She was treated with benzodiazepines, antipsychotics, and mood stabilizers. Since she showed no improvement, she was transferred to another health facility where the progression of neurological deterioration persists due to an altered state of consciousness, aphasia, and catatonic position, leading to a diagnosis of acute encephalitis. A cerebrospinal fluid study was conducted with a request to determine anti-N-methyl-D-aspartate receptor antibodies, which returned positive. Management began with plasmapheresis sessions without a favorable response, prompting the decision to use Rituximab, resulting in progressive improvement in the clinical condition. Conclusion: Anti-N-methyl-D-aspartate receptor encephalitis represents a diagnostic challenge due to its similarity with psychiatric disorders; this pathology should be considered in cases with imprecise clinical presentations. Determining anti-N-methyl-D-aspartate receptor immunoglobulin G in cerebrospinal fluid represents the study of choice. Timely initiation of treatment allows for damage limitation and prompt patient recovery.