CSF markers in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS, 'Lou Gehrig disease') is the most common, progressive, neurodegenerative, motor neuron disease, causing damage to upper and lower motor neurons, leading to paralysis and death within 3-5 years. Majority of ALS cases are sporadic ALS (SALS) and only 5-10 % of cases are familial ALS (FALS). Pathogenesis of ALS is complicated and still unclear, including genetic, glutamate excitotoxicity, oxidative stress, mitochondrial dysfunction, neurofilament accumulation, impaired trophic support, altered glial function, viral infection, immune imbalance and impairment of the blood-brain, blood-spinal cord and blood-cerebrospinal fluid barriers (BBB/BSCB/BCSFB). The CSF analysis is still one of the basic laboratory tools and might reflect pathophysiological alterations in the course of the disease and could provide an insight into disease pathomechanisms. The most important aim of its analysis is evaluation of blood-CSF barrier, which is altered in 46 % of ALS patients. The CSF biomarkers may give insight into ALS pathophysiology and may be useful for early, presymptomatic diagnosis, therapeutic monitoring and the development of new therapeutic strategies. This review summarizes the general concepts of biomarkers in CSF of ALS patients and their potential usefulness in further research.