Encéphalite à anticorps anti-récepteur N-Méthyl-D-Aspartate associée à une neuroborréliose de Lyme : difficultés diagnostiques et thérapeutiques

Résumé

Background: Autoimmune encephalitis (AIE) is a group of rare neurological diseases characterized by various neuropsychiatric signs associated with antibodies targeting neuronal proteins. Anti-NMDAR Encephalitis is an AIE recently described in the pediatric population. Case: A 9-year-old girl was admitted for status epilepticus associated with hypersomnia, hallucination and unmotivated laughter evolving for 3 months. Diagnosis of AIE associated with Lyme neuroborreliosis was made when tests confirmed positive anti-NMDAR antibodies in CSF and positive Lyme antibodies. The outcome was good after receiving two doses of IVIG and appropriate antibiotics. Conclusion: Suspecting auto-immune encephalopathy is essential in the differential diagnosis of encephalitis, as early treatment can significantly influence the outcome.