Status epilepticus (SE) is a rare but serious medical emergency in which the brain’s natural mechanisms for stopping a seizure fail, or other mechanisms activate that cause the seizure to persist abnormally. A seizure is considered SE when it lasts longer than 5 minutes, or when multiple seizures occur in rapid succession without full recovery of consciousness in between.
If a seizure persists beyond 30 minutes, it may result in long-term complications affecting not only the brain but also other vital organs such as the heart and kidneys.
Types of Status Epilepticus
SE can be either convulsive or non-convulsive, depending on whether visible motor symptoms are present.
Convulsive status epilepticus usually arises from a generalized or secondarily generalized epileptic seizure. It is characterized by rhythmic jerking (clonic movements), salivation, rapid eye movements, and may be accompanied by fluctuating levels of consciousness.
Non-Convulsive Status Epilepticus (NCSE) may be more subtle. The patient may appear confused, respond inappropriately, or even present with delirium. In some cases, NCSE is seen in patients who are in a coma. Because of its subtler presentation, it may be misdiagnosed, and diagnosis often relies on findings from an EEG (electroencephalogram).
Causes of Status Epilepticus
SE can have various underlying causes, including:
- Fever
- Stroke
- Low levels of antiepileptic medication
- Head trauma
- Central nervous system infections
- Alcohol or drug abuse, or sudden withdrawal
In about 20% of cases, no specific cause can be identified despite thorough investigation. These are referred to as status epilepticus of unknown origin.
In some instances, SE may be the first manifestation of epilepsy. This scenario may indicate a condition known as NORSE (New-Onset Refractory Status Epilepticus), which occurs in individuals with no prior history of epilepsy. NORSE most commonly affects children, young adults, and individuals over the age of 60.