Recurrent encephalitis and stroke following cessation of acyclovir prophylaxis in a patient with neonatal herpes simplex virus with RNF213 mutation

Abstract Objective Herpes simplex virus (HSV) encephalitis can be associated with many secondary neurological complications, but having multiple episodes of recurrent neurological complications is rare in an individual. Understanding the course of each complication can reduce time to diagnosis and adequate treatment. Additionally, we postulate the role of RNF213 mutation in HSV susceptibility. Methods We describe a unique presentation of HSV‐1 encephalitis in an infant with a pathogenic RNF213 mutation who went on to develop multiple rare neurological complications over the course of her illness. Results Our patient was first diagnosed with neonatal HSV‐1 encephalitis at age 2 weeks. She had recurrence of HSV encephalitis (HSE) with associated vasculopathy that led to right middle cerebral artery and posterior cerebral artery infarctions at 13 months, and then later developed post‐HSE anti‐N‐methyl‐ d‐aspartate receptor encephalitis. All of this occurred concomitant with RNF213 mutation. Interpretation This patient demonstrates that, though rare, multiple neurological complications can occur in a single person, thus highlighting the importance of close surveillance of patients with a history of neonatal HSE and pursuing a broad differential in patients with subtle or recurrent symptoms. Furthermore, we propose a potential role of RNF213 mutation in the pathogenesis of our patient's multiple medical conditions.