Encefalitis asociada a anticuerpos antirreceptor de NMDA: descripción de dos casos en población infantojuvenil

Abstract

The clinical diagnosis of encephalitis due to anti-glutamate receptor N-methyl D-aspartate (NMDA) antibodies (anti-NMDA encephalitis) is made more complex by the fact that psychiatric clinical features are usually predominant in the early stages. This can lead to a delay in the diagnosis, treatment and prognosis of the disease.We report on two clinical cases attended by the Child/Youth Psychiatry Section of our hospital, in collaboration with the Paediatric and Neurology services. Case 1: a 4-year-old male who was referred owing to behavioural alterations and the regression of previously acquired skills. Case 2: a 13-year-old female who was admitted due to a behavioural disorder within the context of a possible initial psychotic episode. In both cases appropriate complementary tests were performed, including lumbar puncture and anti-NMDA antibodies, which were positive. Once the diagnosis of anti-NMDA encephalitis had been reached, treatment was started: in the first case, with intravenous perfusion of corticoids and immunoglobulins, while in the second rituximab had to be associated. Both patients progressed towards clinical improvement.Over the last two years there has been an increase in the number of cases of anti-NMDA encephalitis diagnosed in the child/youth population. It is a neuropsychiatric, autoimmune condition, which can correspond to a paraneoplastic syndrome. Follow-up and transvaginal ultrasonography as well as thoracoabdominal computerised axial tomography scans are recommended for at least two years after diagnosis. Early diagnosis and treatment are important, which means that a multi- and interdisciplinary approach is required.