RESUMO
INTRODUCTION: 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. CASE REPORTS: 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. CONCLUSIONS: 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.
