NEFL and delirium: Ehler et al evaluated the levels of Nf-L from the CSF and blood in a pilot study including 20 patients with sepsis and 5 patients without sepsis, and found that plasma Nf-L levels were higher in sepsis compared to patients without sepsis, having a significant increase from day 1 to day 7 only in septic patients.21The increase in plasma Nf-L levels over time was significantly greater in sepsis patients experiencing delirium, as assessed by the CAM-ICU score, compared to those without delirium.