Marques TM, et al. - In patients with clear signs of parkinsonism but uncertain diagnosis, researchers examined the diagnostic ability of serum neurofilament light chain (NFL). For this investigation, serum samples were gathered from these patients. After 3 years of follow-up, clinical diagnoses of Parkinson disease (PD) and atypical parkinsonism disorders (APDs) were established and updated again after a maximum of 12 years. According to findings, serum NFL levels were pointedly elevated in APD vs PD and were highly accurate in discriminating APDs from PD. Findings suggested that serum NFL could be an effective biomarker for identifying APD, even when clinical symptoms were not conclusive.