Publications & Posters

Serum neurofilament light chain levels in the intensive care unit: comparison between severely ill patients with and without COVID-19

Annals of Neurology |December 30, 2020

Sutter R, Hert L, De Marchis GM, Twerenbold R, Kappos L, Naegelin Y, Kuster GM, Benkert P, Jost J, Maceski AM, Rüegg S, Siegemund M, Leppert D, Tschudin-Sutter S and Kuhle J

Ann Neurol. 2021



There is emerging evidence for multifarious neurological manifestations of coronavirus disease 2019 (COVID‐19), but little is known regarding whether they reflect structural damage to the nervous system. Serum neurofilament light chain (sNfL) is a specific biomarker of neuronal injury. We measured sNfL concentrations of 29 critically ill COVID‐19 patients, 10 critically ill non–COVID‐19 patients, and 259 healthy controls. After adjusting for neurological comorbidities and age, sNfL concentrations were higher in patients with COVID‐19 versus both comparator groups. Higher sNfL levels were associated with unfavorable short‐term outcome, indicating that neuronal injury is common and pronounced in critically ill patients. ANN NEUROL 2021

Neurologic symptoms have been reported in up to 36% of patients with coronavirus disease 2019 (COVID‐19).12 Animal models3 and postmortem studies in humans45 suggest neurotropism of other, closely related coronaviruses (especially severe acute respiratory syndrome coronavirus [SARS‐CoV]), and investigations on the potential of SARS‐CoV2 to damage the peripheral and central nervous system (CNS) are needed to distinguish neurologic symptoms related to structural damage versus reversible neurological dysfunction. Such differentiation may be critical to prognosticate long‐term sequelae.

Neurofilament light chain (NfL) represents a main constituent of the neuronal cytoskeleton and plays a role in axonal growth, stability, and intracellular transport6; serum NfL (sNfL) is a blood‐based marker specifically reflecting neuroaxonal damage, as shown in studies including acute (ischemic stroke, hypoxic–ischemic encephalopathy)78 and chronic (multiple sclerosis and cerebral small vessel disease)910 diseases of the CNS.

The aim of this study was to test whether in critically ill patients COVID‐19 infection is associated with neuronal damage, based on quantitation of sNfL levels.