A prospective cohort study to identify clinical, biological and imaging features that predict etiology of acute encephalitis

Publié le 20 mai 2020
Mis à jour le 9 octobre 2023

Background: new diagnostic tools have been developed to improve the diagnosis of infectious encephalitis. Using a prospective cohort of encephalitis patients, our objective was to identify possible clusters of patients with similar patterns among encephalitis of unknown cause, and to describe to what extent the patient's initial presentation may be predictive of encephalitis etiology, particularly Herpes simplex virus (HSV) and Varicella-zona virus (VZV). Methods: the national cohort of infectious encephalitis in France (ENCEIF) is an ongoing prospective cohort study implemented in France in 2016. Patients presenting with a documented or suspected acute infectious encephalitis were included. Focusing on the variables describing the initial presentation, we performed a factor analysis of mixed data (FAMD) to investigate a pattern of association between the initial presentation of the patient and the etiologic pathogen. Results: as of 1st August 2018, data from 349 patients were analysed. The most frequent pathogens were HSV (25%), VZV (11%), Tick-borne encephalitis virus (6%), Listeria (5%), Influenza virus (3%), and encephalitis of unknown cause (EUC) (34%). Using the FAMD, it was not possible to identify a specific pattern related to the group of EUC. Age, temporal or haemorrhagic lesions, and cerebral spinal fluid lymphocytosis were significantly associated with HSV/VZV encephalitis. Conclusion: no initial clinical/imaging/biology pattern was identified at admission among EUC, despite the improvement of diagnostic tools. In this context, the recommendation for a universal, early probabilistic initial treatment against HSV and VZV is still relevant, regardless of the initial clinical presentation of the encephalitis.

Auteur : Le Maréchal Marion, Mailles Alexandra, Seigneurin Arnaud, Tattevin Pierre, Stahl Jean-Paul, Épaulard Olivier
Clinical Infectious Diseases, 2021, vol. 73, n°. 2, p. 264-270