ABSTRACT
La encefalitis debida a anticuerpos contra receptores N-metil-D-aspartato (NMDA)es una entidad potencialmente tratable, caracterizada por síntomas neuropsiquiátricos que incluyen crisis epilépticas, alteración de conciencia, catatonía y trastornos autonómicos, y desencadenada por una respuesta inmunológica mediada por antígenos. A su vez, el síndrome DRESS (sigla en inglés de Reacción a drogas con eosinofília y síntomas sistémicos) es un cuadro de hipersensibilidad retardada mediada por células, frecuentemente asociada a fármacos antiepilépticos aromáticos. Se presenta el caso de una paciente joven que debutó con crisis epilépticas inicialmente fármaco-sensibles, desarrolló luego el síndrome de DRESS secundario a fenitoína. Cursó posteriormente con trastornos de memoria y lenguaje, alteraciones conductuales y estado catatónico y presentó anticuerpos contra receptores NMDA en el líquido cefalorraquídeo. Ambas entidades respondieron a inmunoterapia con corticoides, lo cual contribuiría a explicar una asociación fisiopatogénica entre estas dos entidades inmunomediadas.
N-Methyl-D-Aspartate receptor encephalitis is a potentially treatable entity characterized by neuropsychiatric symptoms including epileptic seizures, disruption of consciousness, catatonia, and autonomic disorders, and triggered by an immunological response mediated by an antigen. In turn, the DRESS syndrome (Drug Reaction with Eosinophilia and Systemic Symptoms) is a delayed cell-mediated hypersensitivity reaction, frequently associated with antiepileptic aromatic drugs. The case is presented of a young patient who debuted with epileptic seizures initially drug-sensitive, developedthen DRESS syndrome secondary to the use of phenytoin, and later presented disorders of memory and language, behavioral alterations and catatonic state, and presented anti- NMDA receptor antibodies in CSF. Both entities responded to corticoid immuno-therapy, which could contribute to explain a pathogenic association between these two immunomediated entities.
ABSTRACT
BACKGROUND: N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-isoxazole-4-propinoic acid (AMPA) receptors bound to postsynaptic density-95 (PSD-95) and alpha isoform of calcium/calmodulin-dependent protein kinase II (alphaCaMKII) is fundamentally involved in the regulation of working memory. The aim of present study was to investigate the alterations of NMDA and AMPA receptors responsible for hippocampal synaptic dysfunction and selective neuronal cell death after chronic renal failure (CRF) which may be associated with impairment of working memory. METHODS: Altered interactions between NMDA and AMPA receptors and PSD-95 and alphaCaMKII were analyzed in the cornu ammonis (CA) 1 and CA3/dentate gyrus (DG) subfields of the uremic rat hippocampi using the immunoblotting and immunoprecipitation methods. RESULTS: Uremia induced by CRF produced necrotic cell death and decreased neuronal nucleoli protein levels in the hippocampal CA1 subfield, but not in the CA3/DG subfields. The CA1 subfields of CRF rats exhibited significant decreases and increases, respectively, in the expressions of PSD-95/NR2B and alphaCaMKII/NR2A synaptic complex. Moreover, increased phosphorylation of glutamate receptor type 1 (GluR1) AMPA receptor at ser831 was observed in the CA1 subfield after CRF. CONCLUSION: These hippocampal CA1 neuronal vulnerability may be responsible for memory dysfunction after CRF as mediated by an increase in NR2A-containing NMDA receptors bound to alphaCaMKII and subsequent activation of GluR1-containing AMPA receptors caused by the phosphorylation of GluR1 at ser831.