Detection of Brain Somatic Mutations in Cerebrospinal Fluid from Refractory Epilepsy Patients.

Brain mosaic mutations are a major cause of refractory focal epilepsies with cortical malformations such as focal cortical dysplasia, hemimegalencephaly, malformation of cortical development with oligodendroglial hyperplasia in epilepsy, and ganglioglioma. Here, we collected cerebrospinal fluid (CSF) during epilepsy surgery to search for somatic variants in cell-free DNA (cfDNA) using targeted droplet digital polymerase chain reaction. In 3 of 12 epileptic patients with known somatic mutations previously identified in brain tissue, we here provide evidence that brain mosaicism can be detected in the CSF-derived cfDNA. These findings suggest future opportunities for detecting the mutant allele driving epilepsy in CSF. ANN NEUROL 2021;89:1248-1252.

Tocilizumab treatment for new onset refractory status epilepticus.

We investigated the therapeutic potential of the interleukin-6 receptor inhibitor tocilizumab in 7 patients with new onset refractory status epilepticus (NORSE) who remained refractory to conventional immunotherapy with rituximab (n = 5) or without rituximab (n = 2). Status epilepticus (SE) was terminated after 1 or 2 doses of tocilizumab in 6 patients with a median interval of 3 days from the initiation. They had no recurrence of SE during the observation. However, 2 patients experienced severe adverse events related to infection during the tocilizumab therapy. Further prospective controlled studies are warranted to validate the efficacy and safety of tocilizumab in patients with NORSE. Ann Neurol 2018;84:940-945.

Fibronectin is a potential cerebrospinal fluid and serum epilepsy biomarker.

PURPOSE: Previous studies have demonstrated that fibronectin (FN) levels are increased in brain tissues from patients and animals with epilepsy. This study aimed to assess FN levels in cerebrospinal fluid (CSF) and serum samples from patients with epilepsy. METHODS: Fibronectin levels were assessed in CSF and serum samples from 56 patients with epilepsy (27 and 29 individuals with intractable epilepsy and nonintractable epilepsy, respectively) and 25 healthy controls, using sandwich enzyme-linked immunosorbent assays (ELISA). RESULTS: CSF-FN levels were higher in patients with epilepsy (8.07 ± 1.51 mg/l versus 6.20 ± 1.18 mg/l, p<0.05) than in the control group. In addition, serum-FN levels in the group with epilepsy and in the control group were 236.96 ± 65.7 mg/l and 181.43 ± 72.82 mg/l, respectively, indicating a statistically significant difference (p=0.01). Interestingly, serum- and CSF-FN levels in individuals with epilepsy were not affected by antiepileptic drug and duration of epilepsy. Of note, the increase of CSF- and serum-FN levels was more pronounced in subjects with intractable epilepsy than in patients with nonintractable epilepsy. CONCLUSION: Serum- and CSF-FN levels constitute a potential clinical diagnostic biomarker for epilepsy and could also be used for differential diagnosis.

PD-1 Is an Immune-Inflammatory Potential Biomarker in Cerebrospinal Fluid and Serum of Intractable Epilepsy.

PURPOSE: Previous studies have demonstrated that immune and inflammatory factors play an important role in recurrent seizures. The PD-1-PD-L pathway plays a central and peripheral immunosuppressive role by regulating multiple signaling pathways during the inflammatory and immunologic processes. This study is aimed at assessing PD-1 levels in cerebrospinal fluid (CSF) and serum samples from patients with intractable epilepsy. METHODS: PD-1 levels were assessed in CSF and serum samples from 67 patients with intractable epilepsy (41 and 26 individuals with partial seizure and intractable status epilepticus, respectively) and 25 healthy controls, using flow cytometric analysis and sandwich enzyme-linked immunosorbent assays (ELISA). RESULTS: Serum-PD-1+CD4+CD25high Treg levels in the experimental groups and the control group were 10.26 ± 2.53 (PS group), 35.95 ± 27.51 (ISE group), and 4.69 ± 2.44 (control group). In addition, CSF-PD-1 level in patients with epilepsy was higher than that in the control group (50.45 ± 29.56 versus 19.37 ± 4.51), indicating a statistically significant difference (P < 0.05). Interestingly, serum- and CSF-PD-1 levels in individuals with epilepsy were not affected by antiepileptic drug and treatment course, but by epilepsy onset level. Of note, the increase of CSF- and serum-PD-1 levels was more pronounced in subjects with intractable status epilepticus than those with partial seizure. CONCLUSION: Serum- and CSF-PD-1 levels constitute a potential clinical diagnostic biomarker for intractable epilepsy and could also be used for differential diagnosis.

Chitinase-3-like protein 1 may be a potential biomarker in patients with drug-resistant epilepsy.

The mechanisms of the pathogenesis of epilepsy remain unclear. Recent research shows that the inflammatory process occurring in the brain may be a common and critical mechanism of seizures. Chitinase-3-like protein 1 (CHI3L1 or YKL-40) is a newly discovered inflammatory factor. We aimed to evaluate the role of YKL-40 as a biomarker for epilepsy. 124 subjects were classified as control group (n = 23), new-diagnosis epilepsy group (NDE, n = 34), drug responsive epilepsy group (DPE, n = 37), and drug-resistant epilepsy group (DRE, n = 30) YKL-40 was measured by ELISA in serum and cerebrospinal fluid (CSF). The concentrations of serum and CSF YKL-40 and its diagnostic accuracy for epilepsy were analysed. Patients with DRE had higher concentrations of YKL-40 in serum and CSF, while patients with NDE and DPE had increased YKL-40 levels in CSF but not serum in comparison with control. Moreover, serum and CSF YKL-40 provide high diagnostic accuracy for DRE. YKL-40 may play a possible pathogenic role in epilepsy. YKL-40 may represent a potential biomarker of brain inflammation in patients with DRE.

Alpha-synuclein is a potential biomarker in the serum and CSF of patients with intractable epilepsy.

PURPOSE: Intractable epilepsy is a brain disorder characterized by recurrent seizures and intracellular alpha-synuclein (αS) deposits; however, the neurobiological basis of this protein accumulation is still poorly understood. This is the first study aiming to assess whether the increase of αS concentrations in the serum and CSF (cerebrospinal fluid) could serve as a marker for αS deposition in the brain and diagnosis of epilepsy. METHODS: This investigation enrolled 67 epileptic patients (40 with intractable epilepsy; 13 with newly diagnosed epilepsy, and 14 with non-intractable epilepsy). CSF and serum samples were collected from each patient and were assessed by ELISA. RESULTS: It was established that the concentration of αS in the CSF and serum was elevated in the epilepsy patients, as compared to the control. However, the results of the subgroup analysis revealed that levels of αS in the serum and CSF were increased in the intractable epileptic patients (CSF: 11.12 ± 4.18 ng/ml; serum: 52.93 ± 22.11 ng/ml), whereas there was no difference in the groups with the newly diagnosed (CSF: 34.998 ± 14.96 ng/ml; serum: 7.77 ± 3.41 ng/ml) and non-intractable epilepsy (CSF: 8.93 ± 4.83 ng/ml; serum: 34.11 ± 17.53 ng/ml). CONCLUSION: Overall, we found that the rise of the αS content in the serum and CSF may facilitate the identification of intractable epilepsy; therefore, the determination of αS rates may serve as a valuable prognostic marker in the clinical assessment.

Efficacy of the Ketogenic Diet for the Treatment of Refractory Childhood Epilepsy: Cerebrospinal Fluid Neurotransmitters and Amino Acid Levels.

OBJECTIVE: The mechanisms of the ketogenic diet remain unclear, but several predictors of response have been proposed. We aimed is to study the relationship between the etiology of epilepsy, cerebrospinal fluid neurotransmitters, pterins, and amino acids, and response to a ketogenic diet. METHODS: We studied 60 patients who began classic ketogenic diet treatment for refractory epilepsy. In 24 of 60 individuals, we analyzed cerebrospinal fluid neurotransmitters, pterins, and amino acids in baseline conditions. Mean age at epilepsy onset was 24 months, 83.3% were focal epilepsies, and in 51.7% the etiology of the epilepsy was unknown. RESULTS: Six months after initiating the ketogenic diet, it was effective (greater than a 50% reduction in seizure frequency) in 31.6% of patients. We did not find a link between rate of efficacy for the ketogenic diet and etiologies of epilepsy, nor did we find a link between the rate of efficacy for the ketogenic diet and cerebrospinal fluid pterins and biogenic amines concentrations. However, we found statistically significant differences for lysine and arginine values in the cerebrospinal fluid between ketogenic diet responders and nonresponders, but not for the other amino acids analyzed. SIGNIFICANCE: The values of some amino acids were significantly different in relationship with the ketogenic diet efficacy; however, the epilepsy etiology and the cerebrospinal fluid biogenic amine and pterin values were not.