Blood biomarkers in epilepsy

Robust and accessible biomarkers are greatly needed in epilepsy. Diagnostic and prognostic precision in the clinic needs to improve, and there is a need for objective quantification of seizure burden. In recent years, there have been advances in the development of accessible and cost-effective blood-based biomarkers in neurology, and these are increasingly studied in epilepsy. However, the field is in its infancy and specificity and sensitivity for most biomarkers in most clinical situations are not known. This review describes advancements regarding human blood biomarkers in epilepsy. Examples of biochemical markers that have been shown to have higher blood concentrations in study subjects with epilepsy include brain proteins like S100B or neuronal specific enolase, and neuroinflammatory proteins like interleukins, and tumor necrosis factor-alpha. Some of the blood biomarkers also seem to reflect seizure duration or frequency, and levels decrease in response to treatment with antiseizure medication. For most biomarkers, the literature contains seemingly conflicting results. This is to be expected in an emerging field and could reflect different study populations, sampling or analysis techniques, and epilepsy classification. More studies are needed with emphasis put on the classification of epilepsy and seizure types. More standardized reporting could perhaps decrease result heterogeneity and increase the potential for data sharing and subgroup analyses.

Is the antiseizure effect of ketogenic diet in children with drug-resistant epilepsy mediated through proinflammatory cytokines?

In order to understand whether the antiseizure mechanism of ketogenic diet (KD) is mediated through its anti-inflammatory effect, we measured the serum concentrations of cytokines IL- 1β and IL-6 in 21 children with drug-resistant epilepsy. We found a significant reduction in the levels of serum IL- 1β and IL-6 levels at one-year of KD therapy compared to baseline. However, we did not find any correlation between decrease in the serum concentrations of these interleukins with the reduction in seizure frequency at one-year of KD therapy, which may be due to the small sample size and heterogeneous patient population we studied. Future studies should try to overcome these limitations.

Inflammatory signs and epileptic crisis in patients admitted in an emergency unit

ABSTRACT Objective: To evaluate inflammatory signs presented in medical records of patients with a main diagnosis of epileptic seizures, admitted in an emergency unit. Method: Cross-sectional and retrospective study. The sample was composed of 191 medical records, from children, adolescents, adults, and elders, with a clinical diagnosis of epileptic seizures, admitted between June 2016 and June 2017 at the emergency unit of a hospital in Porto Alegre/RS. Results: The prevalent inflammatory signs were tachypnea (33.5%) and/or fever (27.2%) associated with leukocytosis (P=0.030). Children/adolescents had seizures less frequently (P=0.010) and these were due to fever (P=0.000). Adults presented seizures more frequently (P=0.006), which were related to medication/intoxication (P=0.000). In elders, seizures occurred due to metabolic or circulatory abnormalities (P=0.000), less often due to fever (P=0.005). Conclusion: Seizures are related to fever and tachypnea, being caused by different etiologies according to age, being more frequent in adults. Fever is related to leukocytosis, regardless of age.