AAN 2025 | Understanding the etiology of acute symptomatic seizures

So, acute symptomatic seizures are those seizures that have happened in a close temporal correlation with a brain injury. And this brain injury can be structural or non-structural. Which are the etiologies of structural and non-structural brain injuries? Structural, as you can imagine, are traumatic brain injuries, ischemic stroke, hemorrhagic stroke, or tumors. These are changing the structure of the brain. The non-structural goes into inflammatory, infection, and toxic metabolic. In infection, we have meningitis and encephalitis. In inflammatory, we have autoimmune meningitis, autoimmune encephalitis. We can also have multiple sclerosis flare or multiple sclerosis diagnosis. And in toxic metabolic, we have all the laboratory abnormalities such as hyponatremia, hypomagnesemia, or we can also have such as baclofen toxicity, alcohol withdrawal, CEP toxicity. Beghi et al., Beghi and colleagues years ago established this definition, but also established the time of temporal correlation based on the etiology of the brain injury. And it was established for epidemiological purposes and for further studies. For patients that had a structural brain injury, the temporal correlation is about seven days. For patients that had a toxic metabolic abnormality like hyponatremia or hypoglycemia, it’s within 24 hours. For patients that have an acute infection, the time can be a little more prolonged. If you have data that support that the infection is currently active, as well as sometimes the bacteria can be resistant to active bacteria medications. So you have data that the disease is still active. It can be more than seven days. It can be up to 14 days. And one of these cases is, for example, with tuberculosis, the mycobacteria tends to be more resistant to certain medications. And then for the inflammatory states, it can be the moment of the diagnosis of the disease, or it can be also during a flare. For example, in a patient that has multiple sclerosis, upon presentation or diagnosis of multiple sclerosis, if the patient had a seizure, that is an acute symptomatic seizure. But if the patient comes in a year also with a flare of multiple sclerosis and had a seizure, that will also be an acute symptomatic seizure during the active phase of the disease, which is a flare in the moment.

This transcript is AI-generated. While we strive for accuracy, please verify this copy with the video.