Brain-derived neurotrophic factor in blood serum and lacrimal fluid of patients with focal epilepsy.

Abstract Objective To evaluate brain-derived neurotrophic factor (BDNF) level in blood serum (BS) and lacrimal fluid (LF) of people with epilepsy (PWE). Methods It was a case-control study of 72 consecutive patients with focal epilepsy (cases, Epilepsy group) and 60 age- and gender-matched healthy volunteers (controls). Based on comorbid depression, two subgroups of PWE were formed. BDNF level was measured by enzyme-linked immunosorbent assay (ELISA) in BS and LF. Results Compared to controls, BDNF level (pg/mL) in PWE was lower both in BS (22,520 ± 3810 vs. 26,360 ± 3090, P Significance In patients with focal epilepsy, BDNF level is decreased both in BS and LF, though with no correlation between them. No association of BDNF levels with age and epilepsy characteristics, as well as the occurrence of depression, was found. Low BDNF level in LF could be considered as a non-invasive biomarker of focal epilepsy.