Epilepsy is a chronic disorder of the brain and the most common serious neurological disorder that affects about 50 million people worldwide. About 70% of those with epilepsy respond to existing treatment with drugs that have been developed for the disease for the past 30 years. That means, that the remaining 30% o not become free of epileptic seizures even if given these medicines.

The causes of epilepsy, which is the continued presence of seizures, still remain something of the mystery. There is a growing body of evidence that suggests local inflammation of the brain is linked to seizures. Inflammation is an immune response to injury and in most cases of inflammation settles down after a period of time. In some patients, inflammation does not settle down and might provoke continued seizures.

Scientists from the University of Liverpool, in collaboration with the Mario Negri Institute in Milan, have now identified a protein that acts as a marker to for whether there is inflammation in the brain. The researchers were looking for ways to spot such inflammation using blood samplesand focused on a protein called high mobility group box-1 or HMGB1, which exists in different forms – called isoforms – in tissues and the bloodstream.

Their findings, published in the Journal of Clinical Investigation, showed a persistent increase in HMGB1 isoforms in patients with newly-diagnosed epilepsy and who had continuing seizure activity despite anti-epileptic drug therapy. There was no such increase in isoforms in patients whose fits were controlled. An accompanying drug study showed that HMGB1 isoforms may predict whether an epilepsy patient will respond to anti-inflammatory drugs. The researchers say their initial findings indicate the need for evaluation in larger-scale trials but could be the start of personalised medical treatment for epilepsy.