Encefalitis por anticuerpos contra el receptor NMDA. Descripción de una paciente sin tumor asociado y revisión de la bibliografía

Abstract

A severe form of acute encephalitis associated to antibodies against the N-methyl D-aspartate (NMDA) receptor has recently been reported. This clinical picture occurs in young people, not always with an underlying tumour and, despite the initial severity, if identified and treated at an early stage, complete recovery without any kind of sequelae can be achieved. We report on a new case and review the body of knowledge currently available on this recently identified condition. A 22-year-old female who visited our centre due to a progressive conduct disorder. Over the days that followed, deterioration in the level of consciousness made it necessary to put her on assisted respiration. Magnetic resonance imaging of the head showed hyperintense lesions mainly in deep temporal regions. A study of the cerebrospinal fluid revealed pleocytosis with a predominance of lymphocytes and antibodies against the NMDA receptor. In the complementary study no underlying tumour was observed. Treatment with corticosteroids and immunoglobulins brought about a slow but steady improvement. After a one-year follow-up there have been no recurrences, no tumours have appeared and the patient has gone back to her usual day-to-day activities. Even a significant temporal atrophy that developed at the beginning of the clinical picture has gradually been seen to resolve itself in neuroimaging studies performed as a control measure. Encephalitis due to anti-NMDA antibodies is a disease that has only recently been characterised, but which, according to currently available data, is relatively frequent. Clinically well defined, suspicion of this condition will make it possible to reach a definitive diagnosis and to establish early treatment.