Neurological outcomes and disability predictors in paediatric herpes simplex virus encephalitis: a multicentre cohort from French tertiary hospitals.

Objective: To identify factors associated with the neurological outcome of HSVE in children.

Methods: In this retrospective multicentric observational study, clinical, paraclinical data at onset and neurological outcomes at last follow-up of children (≥28 days and <18 years old) with HSVE, were studied. Univariate and multivariate analyses were performed to identify factors associated with neurological outcome.

Results: 49 children (mean age of 4.9 ± 5.5 years) were included. At last follow-up of 5.9 ± 3,13 years, 2 children died (4 %) and 37 (76 %) children presented with poor neurological outcome with epilepsy (57 %), intellectual disability (51 %) and language disorders (47 %). Rehabilitation was necessary for 76 % and 59 % had abnormal academic performances. At onset, younger age and seizures were significantly associated to language disorders (p < 0.01), motor disabilities (p = 0.01), and intellectual disabilities (p = 0.01) in univariate analysis. Abnormal MRIs were more frequent in children with neurological sequalae (p = 0.01). Multivariate analyses identified that: (1) epilepsy occurred more frequently in females (p = 0.03), with insular lesions (p = 0.048); (2) language disorders were more common in children who had seizures at onset (p 0.02); (3) motor disorders were more frequent in younger children (p = 0.03) with thalamic lesions (p = 0.04).

Conclusions: Our findings indicate that despite decrease in mortality rates, neurological disabilities in children with HSVE still persist at high levels. This underscores the need to enhance HSVE management strategies. Moreover, the identified risk factors associated with poor neurological outcomes can aid in identifying high-risk children, facilitating the implementation of alternative treatment approaches such as immunotherapy or intensive rehabilitation.