Electroencephalography for prognostication of outcome in adults with severe herpes simplex encephalitis

Lina Jeantin; Claire Dupuis; Geoffroy Vellieux; Pierre Jaquet; Etienne de Montmollin; Jean-François Timsit; Romain Sonneville; ENCEPHALITICA Study Group

doi:10.1186/s13613-023-01110-3

Electroencephalography for prognostication of outcome in adults with severe herpes simplex encephalitis

Ann Intensive Care. 2023 Feb 23;13(1):10. doi: 10.1186/s13613-023-01110-3.

Authors

Lina Jeantin¹, Claire Dupuis², Geoffroy Vellieux^{3

4}, Pierre Jaquet⁵, Etienne de Montmollin^{6

7}, Jean-François Timsit^{6

7}, Romain Sonneville^{8

9}; ENCEPHALITICA Study Group

Collaborators

ENCEPHALITICA Study Group:
Mikael Alves, Laurent Argaud, Pierre Bailly, François Barbier, Lila Bouadma, Noelle Brulé, Fabrice Bruneel, Russell Chabanne, Marie Conrad, Daniel da Silva, Frederic Dailler, Delphine Daubin, Sophie Demeret, Nicolas Lerolle, Julien Marechal, Bruno Mourvillier, Ahmed El Kalioubi, Benjamine Sarton, Stein Silva, Vincent Susset, Jean Marc Tadié, Jean-Françoit Timsit, Michel Wolff, Alexandre Lautrette, Emmanuel Novy, Bertrand Guidet, François Mateos, Clément Brault, Quentin Maestraggi, Keyvan Razazi, Jean-Pierre Quenot, Aurélie Joret, Albrice Levrat, Alexandre Massri, Alexandre Robert, Damien Contou, Jean-Paul Mira, Gaudry Stephane, Guillaume Voiriot, Asael Berger, Vincent Das, Nicolas Engrand, Martin Murgier, Shidasp Siami, Sami Hraiech, Eric Mariotte, Claire Ragot, Annabelle Stoclin, Pierre Trouiller, Mathieu Schmidt, Charline Sazio

Affiliations

¹ Department of Neurology, GHU Paris Psychiatrie et Neurosciences, Université de Paris, Paris, France.
² Department of Intensive Care Medicine, Clermont-Ferrand University Hospital, 63000, Clermont-Ferrand, France.
³ Paris Brain Institute, ICM, Inserm, CNRS, Sorbonne Université, 75013, Paris, France.
⁴ Department of Neurophysiology, Pitie-Salpêtrière University Hospital, AP-HP, Paris, France.
⁵ Department of Intensive Care Medicine, Delafontaine Hospital, Saint Denis, France.
⁶ IAME, INSERM, UMR1137, Université Paris Cité, Paris, France.
⁷ Department of Intensive Care Medicine, Bichat-Claude Bernard University Hospital, AP-HP, 46 Rue Henri Huchard, 75877, Paris Cedex, France.
⁸ IAME, INSERM, UMR1137, Université Paris Cité, Paris, France. romain.sonneville@aphp.fr.
⁹ Department of Intensive Care Medicine, Bichat-Claude Bernard University Hospital, AP-HP, 46 Rue Henri Huchard, 75877, Paris Cedex, France. romain.sonneville@aphp.fr.

Abstract

Background: Electroencephalography (EEG) is recommended for the practical approach to the diagnosis and prognosis of encephalitis. We aimed to investigate the prognostic value of standard EEG (_stdEEG) in adult patients with severe herpes simplex encephalitis.

Methods: We performed a retrospective analysis of consecutive ICU patients with severe herpes simplex encephalitis in 38 French centers between 2006 and 2016. Patients with at least one _stdEEG study performed at ICU admission were included. _stdEEG findings were reviewed independently by two investigators. The association between _stdEEG findings (i.e., background activity, lateralized periodic discharges, seizures/status epilepticus, and reactivity to painful/auditory stimuli) and poor functional outcome, defined by a score on the modified Rankin Scale (mRS) of 3 to 6 (moderate to severe disability or death) at 90 days, were investigated.

Results: We included 214 patients with at least one available _stdEEG study. The first _stdEEG was performed after a median time of one (interquartile range (IQR) 0 to 2) day from ICU admission. At the time of recording, 138 (64.5%) patients were under invasive mechanical ventilation. Lateralized periodic discharges were recorded in 91 (42.5%) patients, seizures in 21 (9.8%) and status epilepticus in 16 (7.5%). In the whole population, reactivity to auditory/noxious stimuli was tested in 140/214 (65.4%) patients and was absent in 71/140 (33.2%) cases. In mechanically ventilated patients, _stdEEG reactivity was tested in 91/138 (65.9%) subjects, and was absent in 53/91 (58.2%) cases. Absence of reactivity was the only independent _stdEEG finding associated with poor functional outcome in the whole population (OR 2.80, 95% CI 1.19 to 6.58) and in the subgroup of mechanically ventilated patients (OR 4.99, 95% CI 1.6 to 15.59). Adjusted analyses for common clinical predictors of outcome and sedation at time of _stdEEG revealed similar findings in the whole population (OR 2.03, 95% CI 1.18 to 3.49) and in mechanically ventilated patients (OR 2.62, 95% CI 1.25 to 5.50).

Conclusions: Absence of EEG reactivity to auditory/noxious stimuli is an independent marker of poor functional outcome in severe herpes simplex encephalitis.

Keywords: Critical care outcomes; Electroencephalography; Encephalitis; Functional status; Herpes simplex; Prognosis.