What is Epilepsia Partialis Continua?
Epilepsia partialis continua (EPC) is an uncommon brain disorder where someone repeatedly experiences localized seizures over hours, days, or even years, but remains aware of their surroundings. It can show itself in various ways, including shaking or twitching in just one area of the body (myoclonic epilepsy, localized myoclonus), seizures that start in one part of the body and spread (Jacksonian epilepsy), and seizures affecting both the senses and muscle movement (sensorimotor clonic seizures). The causes are complex, with both the outer layer of the brain (cortical) and the deeper brain structures (subcortical) potentially involved.
This disorder is often identified by the localized nature of the seizures with preserved awareness and a temporary confusion and weakness after the seizure (Todd paralysis). However, this isn’t a surefire sign of EPC, as there have been exceptions. Doctors typically treat EPC using a variety of epilepsy medications, and by determining and addressing the root cause of the seizures.
The disorder was first identified in 1894 by Russian neurologist Aleksei Kozhevnikov. He believed that the seizures were due to a localized inflammation in the brain (focal cortical encephalitis) and the consequential inflammation of brain motor fibers, which perform various tasks involving movement. In 1958, a condition called Rasmussen syndrome, which presents with seizures similar to EPC, was formally described. Since then, many scientists have suggested different possible ways this syndrome develops and affects the body.
What Causes Epilepsia Partialis Continua?
There are countless neurological diseases related to a condition called epilepsia partialis continua (EPC), which makes the nature of the disease quite varied. The reason for EPC is basically the same as other types of epilepsy, as it boils down to unusual electrical activity in the brain. This can be triggered by various disorders and conditions, including physical damage to the brain, developmental brain disorders (like Tuberous Sclerosis, Sturge-Weber syndrome, and linear sebaceous nevus syndrome), certain drugs, disruption of normal bodily functions due to conditions like high or low salt or sugar levels, or high level of uric acid or waste products in the blood. There can also be neoplastic processes, which means that different types of brain tumors (oligodendroglioma, meningioma, high grade glioma) can cause EPC, and also autoimmune processes, where the body’s immune system attacks the brain, like in autoimmune encephalitides. Another trigger can also be certain types of infections.
There is a rare neurological disease seen in children, called Rasmussen encephalitis or chronic focal encephalitis (CFE), that is strongly associated with EPC according to current research.
Risk Factors and Frequency for Epilepsia Partialis Continua
Epilepsia partialis continua (EPC) is a rare disease that slightly more often affects males than females. The disease is not very common and has mostly been mentioned in individual case reports over the years. According to a study conducted in the United Kingdom, the disease was found to occur once per one million people over a year. Another study in India found the average age of people with EPC to be around 30.2 at a tertiary health care hospital over a 14 year period.
- Epilepsia partialis continua (EPC) is a rare disease that tends to affect males more than females.
- Information about EPC is usually found in individual case reports.
- A UK study found that EPC occurs in about one in one million people over a year.
- In India, the average age of EPC patients was found to be 30.2 at a specialized hospital over 14 years.
Signs and Symptoms of Epilepsia Partialis Continua
Epilepsia Partialis Continua (EPC) is a complex condition that can be associated with numerous diseases. Therefore, a thorough medical history and neurological examination are needed. EPC is typically a type of status epilepticus (ongoing seizures), which affects only one part of the body, lasts for an hour or more, and can cause confusion and weakness after seizures. Because the disease is so complex, patients often show a variety of symptoms, making a thorough medical history and physical exam critical.
The symptoms experienced depend on the severity and characteristics of the underlying condition causing the EPC. Motor symptoms can vary greatly, ranging from quadriparesis (weakness in all four limbs) to a subtle weakness of the soft palate (the soft part at the back of the roof of the mouth). Though sensory symptoms (those affecting the senses) can occur, they’re less common than motor symptoms.
The following can usually be observed:
- Motor symptoms such as differences in limbs’ strength and soft palate weakness
- Sensory changes, though less frequent than motor symptoms
- Symptoms mostly affecting the upper extremities
- Possible changes in mental state, either from post-seizure confusion or the severity of the underlying condition causing EPC
Testing for Epilepsia Partialis Continua
If you’re being evaluated for epilepsia partialis continua (EPC), which is a type of epilepsy with continuous muscle twitching, your doctor might order some lab tests. These are usually aiming to see if there might be other issues causing your symptoms, like metabolic disturbances, problems with the blood vessels in your brain, or cancer.
Imaging studies, like magnetic resonance imaging (MRI), can assist in identifying if you have any abnormal structures in your brain. Two common causes of EPC, focal cortical dysplasia and Rasmussen encephalitis, can be detected using an MRI. Single-photon emission computed tomography (SPECT) can also be helpful in pinpointing the specific region in your brain where the seizures originate from, but this method is mainly used for research and isn’t commonly used in clinics. Standard imaging techniques like a computed tomography (CT) scan or an MRI might not reveal any abnormalities, even if you have EPC.
An electroencephalogram (EEG) is another tool your doctor may use. An EEG measures the electrical activity in your brain. But, an EEG won’t show specific signs of EPC. Instead, you might see spikes, sharp waves, or periodic movements with slow-wave activity. If your EEG shows slow activity in the background, it could suggest that one side of your brain is working differently than the other. But, a normal EEG doesn’t rule out EPC because the region of your brain where the seizures are coming from might be deep within the brain and not picked up by the EEG.
Somatosensory evoked potentials (SSEPs) is another method that could be used. SSEPs measure the brain’s response to sensations like touch and temperature. In EPC, SSEPs can point to the area of the brain where seizures originate from. They can show if your motor cortex (the part of the brain responsible for voluntary movements) is over-responsive to stimuli.
Treatment Options for Epilepsia Partialis Continua
The main cause of epilepsia partialis continua (EPC), a condition characterized by recurrent seizures, determines the initial approach to treatment. The primary goal in managing EPC is to control seizures, often accomplished through the use of anti-epileptic medication (AED). These medications work to calm the overactivity in the brain that leads to seizures.
Some AEDs appear to work better than others for treating EPC, and often, a combination of multiple AEDs is employed. Research suggests that drugs such as phenytoin and phenobarbital might work better than valproate or carbamazepine. In addition, newer AEDs, including levetiracetam, brivaracetam, lacosamide, and zonisamide, can be used because they are generally well tolerated. Another drug, felbamate, has also shown positive effects, especially in cases where other treatments haven’t worked.
If EPC is caused by Rasmussen encephalitis, an inflammatory neurological disease, it can sometimes be managed with immunosuppressive drugs. These are medications that reduce the body’s immune response, reducing inflammation and, hence, symptoms. Promising results have been seen with drugs such as rituximab, tacrolimus, intravenous immunoglobulin (IVIG), and plasma exchange. Some studies have also found benefits from ganciclovir and intraventricular interferon alfa, although these findings are based on very small numbers of patients.
If medical treatment fails to control seizures, surgical interventions like hemispherectomy might be considered. This is a drastic operation that involves removing or disconnecting one hemisphere of the brain and is usually only considered in severe cases. Additionally, emerging techniques such as repetitive transcranial stimulation and botulinum toxin, which are used to disrupt the electrical activity of the brain, have demonstrated some success in specific instances.
What else can Epilepsia Partialis Continua be?
These are some conditions that can affect the brain and nervous system:
- Cerebral venous sinus thrombosis (abnormal blood clotting in the brain)
- Cortical dysplasia (abnormal development in the brain’s cortex)
- Choreiform (a disorder causing involuntary jerky movements)
- Encephalitis (inflammation of the brain)
- Hyperglycemic nonketotic syndrome (a serious complication of high blood sugar)
- Hyponatremia (low sodium level in the blood)
- Hemiballismus (a condition causing violent, rapid movements on one side of the body)
- Perinatal central nervous system injury (injury to the brain during or shortly after birth)
- Rasmussen’s encephalitis (a rare inflammation of the brain)
- Stroke (a condition where the blood supply to part of the brain is cut off)
- Tic disorder (a condition where a person makes sudden, fast movements or sounds that they can’t control)
What to expect with Epilepsia Partialis Continua
The outlook for people dealing with continuous partial seizures, also known as epilepsia partialis continua (EPC), largely depends on what’s causing the condition. For instance, children who have specific types of brain inflammation (like Rasmussen encephalitis) or other deteriorating conditions, usually face a tougher road to recovery. Additionally, children who start having EPC at advanced stages of the illness are more likely to face life-threatening situations.
On the other hand, adults tend to have a better outcome when diagnosed with EPC. This is because the causes in adults can often be reversed. However, there are specific cases where it’s crucial to manage the condition promptly and aggressively. This is because EPC has a tendency to worsen over time or lead to permanent damage to the brain’s structure.
