NEFL and amyotrophic lateral sclerosis: Compared to healthy controls, NfL and pNfH concentrations in CSF, plasma or serum are elevated in ALS [9, 34–38, 40–44, 50, 52, 58–60, 65, 66] as well as other neurological diseases such as frontotemporal dementia (FTD) [37, 38, 67, 68], Alzheimer’s disease [69], stroke [70] and COVID-19 [71].