The Frontal nocturnal epilepsy (ENF) appears during the night, and is manifested by an autonomic activation and unusual motor behavior.
Within this type, there is autosomal dominant nocturnal epilepsy (ADNFLE), which is very rare and is inherited between relatives.
It's about the Seizures During the night, when the person is asleep, although sometimes it can happen during the day.
These seizures can last from a few seconds to minutes, and vary in severity so that some people have only mild episodes, while others may experience sudden and sudden movements of the arms and legs, moving them as if riding a bicycle.
It may also emit sounds such as screams, groans or grunts, so you may believe they are Nightmares or night terrors And not an epilepsy.
In addition, the affected person can even get out of bed and wander around the house, something that is often confused with somnambulism .
The nocturnal epilepsy shares with other types of epilepsy that, just prior to the onset of the attack, there is a pattern of neurological signs called aura . These symptoms include fear, hyperventilation, chills, tingling, dizziness, and feeling of falling into the void.
The cause of seizures is not yet known with exactness. It is believed that they may be more frequent when the person is tired or stressed, but usually do not have known precipitating causes.
This problem seems to occur frequently in the childhood , Around 9 years. Although it can appear until the middle of the adult age, stage where the episodes are usually less frequent and lighter.
On the other hand, these people do not have any intellectual problem related to the disease, however, some have also presented psychiatric disorders as schizophrenia , But it is not thought to be due to epilepsy itself.
Prevalence of nocturnal epilepsy
It is not known exactly, but in a study by Provini et al. (1991) found interesting figures on nocturnal epilepsy. For example:
- Seizures predominate in men in a ratio of 7 to 3.
- The age of onset of nocturnal attacks is variable, but it is much more frequent in children and adolescents.
- There is a family recurrence in 25% of cases, while in 39% there is a family history of parasomnias.
- About 13% of the cases presented antecedents like Anoxia , Febrile seizures or brain alterations observed through Magnetic resonance .
On the other hand, autosomal dominant nocturnal nocturnal epilepsy (ADNFLE) appears to be very rare and its prevalence has not even been accurately estimated. It has now been described in more than 100 families around the world.
Causes
It seems to be due to changes in brain electrical activity during the different stages of sleep. Usually, they occur in Phases of sleep 1 and 2 which are the least deep.
Although it seems to act as a vicious circle, since the lack of sleep that can be caused by seizures may be one of the most common triggers for more attacks. Other factors would be stress Or fever.
However, the original cause of seizures is not yet known.
On the other hand, autosomal dominant nocturnal epilepsy (ADNFLE) is the first epilepsy to be associated with a genetic cause. Specifically, mutations in the CHRNA2, CHRNA4 and CHRNB2 genes have been found in these patients. These genes are responsible for coding Neural nicotinic receptors .
In addition, this type is inherited with an autosomal dominant pattern, which means that a copy of the gene altered by one parent is enough to increase the risk of transmitting epilepsy. However, there are other cases in which it occurs sporadically, since the affected has no family history of the disorder.
symptom
Symptoms of epileptic seizures during the night include...
- Sudden and repetitive motor movements.
- Dystonic posture, or sustained muscular contractions that cause some parts of the body to become twisted or tense.
- Uncontrolled jerking, pushing or pushing.
- Restless sleepwalking.
- dyskinetic characteristics: involuntary movements of the extremities.
- Strong autonomic activation during seizures.
- In a study of the magazine Brain , It is stated that this type of epilepsy constitutes a spectrum of different phenomena, of different intensity, but which represent a continuum of the same epileptic condition.
- During the day, unusual drowsiness or headache.
- Drooling, vomiting or wetting the bed.
- In addition, attacks disrupt sleep, and end up impacting on concentration and performance at work or school.
The most frequent type of seizure during sleep are partial convulsions, ie those that are focal or located in a particular part of the brain .
Diagnosis
It can be difficult to diagnose this condition since the attacks occur when the person sleeps, and the person may not be aware of their own problem. In addition, it is common to be confused with other conditions such as sleep disorders Not related to epilepsy .
According to Thomas, King, Johnston and Smith (2010), if more than 90% of seizures occur during sleep, it is said to have sleep convulsions. However, it should be noted that between 7.5% and 45% of epileptics have some type of seizures while sleeping.
There are no established diagnostic criteria for NFE. In addition, it is difficult to detect it because, through a encephalogram There may be no malfunction.
However, we may suspect NFS if it starts at any age (but especially in infancy) and give brief bouts of sleep characterized by a stereotyped motor pattern.
The techniques to detect it are:
- Brain magnetic resonance (RM) or Computed tomography (TC)
- Daily record of the convulsive activity, for this you can use a camera to record the affected person while sleeping at night.
- At present, there is a clock called Smart Monitor, which has sensors to detect the epileptic seizures in those who carry it. In addition, it connects with the user's mobile to be able to notify parents or caregivers when the child has an epileptic seizure.
This may be more a measure of palliative symptoms than a diagnostic tool, although it may be useful to see if people with epilepsy attacks appear at night.
- For its differential diagnosis, the best tool has been the videoopolisomnographic record (VPSG). However, these records are not available worldwide and are often expensive.
In fact, distinguishing between ENF and motor sleep phenomena not associated with epilepsy can be an arduous task, and if this instrument were used, more cases of NFE would be diagnosed than expected.
- Another instrument that can be useful to detect it is the scale of frontal nocturnal epilepsy and parasomnias.
To assess what type of epilepsy is involved, physicians must examine:
- Type of attack that presents.
- Age at which the seizures began.
- If there is a family history of epilepsy or sleep disorders.
- Other medical problems.
There appears to be no difference in the clinical and neurophysiological findings between nocturnal epilepsy Frontal lobe Sporadic and hereditary.
Do not confuse with...
- Benign neonatal sleep myoclonus : Which may look like epilepsy because it consists of involuntary movements that resemble seizures, such as hiccups or jerks during sleep. However, in a electroencephalogram (EEG) would show that there are no brain changes typical of epilepsy.
- Parasomnias : Are behavioral disorders that occur during sleep without completely disrupting sleep. They encompass enuresis Or"wet the bed,"nightmares, night terrors , somnambulism , Restless legs syndrome, rhythmic movements of sleep or Bruxism .
- Psychiatric disorders.
However, in a study by Miano and Peraita-Adrados (2013), a high percentage of children with nocturnal frontal epilepsy were found who were not previously diagnosed and who appeared to be related to other sleep disorders, which could be the triggers of the seizures Night.
In short, do not confuse one problem with another, but it is important to know that several conditions can occur at the same time along with nocturnal epilepsy.
Forecast
The prognosis is usually good; So that when a child has epilepsy, it usually does not progress further into adulthood.
On the other hand, it must follow the treatment since the frontal nocturnal epilepsy does not return of spontaneous form.
Treatment
Epileptic seizures are mainly controlled through medication, mainly anticonvulsive drugs or Antiepileptics .
However, some of these drugs can have side effects on sleep causing the person to not rest well. That is why it is important to choose the antiepileptic medication to be prescribed to the patient.
Drugs that do not seem to alter sleep and help suppress convulsions are: phenobarbital, phenytoin, carbamazepine, valproate, zonisamide, and oxcarbazepine (among others) (Carney & Greyer, 2005). Oxcarbazepine seems to have the least adverse effects on sleep.
On the other hand, carbamazepine has been found to completely eliminate convulsions in approximately 20% of cases, and gives significant relief by 48% (which means a reduction of seizures by at least 50%).
References
- Autosomal dominant nocturnal frontal lobe epilepsy. (July 5, 2016). Retrieved from the Genetics Home Reference.
- Carney, P.R. & Greyer, J.D. (2005). Clinical Sleep Disorders. Philadelphia: Lippincott, Williams, and Wilkins.
- Combi, R., Dalprà, L., Tenchini, M.L., & Ferini-Strambi, L. (2004). Autosomal dominant nocturnal frontal lobe epilepsy-a critical overview. Journal Of Neurology, 251 (8), 923-934.
- Peraita Adrados, R. (2013). Frontal nocturnal epilepsy infradiagnosticada in infancy as a sleep disorder: study of a series. Journal of Neurology, (5), 257.
- Provini, F., Plazzi, G., Tinuper, P., Vandi, S., Lugaresi, E., & Montagna, P. (n.d). Nocturnal frontal lobe epilepsy - A clinical and polygraphic overview of 100 consecutive cases. Brain, 1221017-1031.
- Sleep and epilepsy. (S.f.). Retrieved on July 8, 2016, from Epilepsy Society.
- Smart Monitor: the watch that alerts on epileptic seizures. (February 10, 2015). Obtained from Biomedical Engineering.
- Thomas, R., King, W., Johnston, J., & Smith, P. (n.d). Awake seizures after pure sleep-related epilepsy: a systematic review and implications for driving law. Journal of Neurology Neurosurgery And Psychiatry, 81 (2), 130-135.
- York Morris, S. (September 25, 2014). Identifying and Treating Nocturnal Seizures.