Epilepsy is the fourth most common neurological disorder and can affect people of any age. The World Health Organization estimates that currently, 50 million people around the world have epileptic seizures. The symptoms and types are very varied, as well as the treatment options and the chances of recovery.
In this article, we explain what this neurological disorder is, its symptoms and types, what it is like in children and young people and what are the possible causes and treatment options for this disease.
What Is Epilepsy?
Also known as seizure disorder, epileptic seizure or epileptic attack, this disorder consists of episodes of uncontrolled electrical activity in the brain originated in the neurons, and that usually lasts for a few seconds.
It is a chronic disorder, meaning that having a single seizure does not necessarily represent or trigger that the affected person suffers from it. In fact, it is estimated that approximately 10% of the world's population has at least one seizure in their lifetime.
Diagnosis
Seizures usually begin between the ages of 5 and 20, but may also occur for the first time in people over 60. Diagnosing this disorder not only considers obvious symptoms but also requires a thorough medical evaluation to determine what happens in the brain.
According to the World Health Organization, epilepsy is diagnosed when there are two or more unprovoked seizures. In other words, the crises must have been repeated for a period of time and spontaneously. However, if a person has a single seizure with no apparent cause, it is recommended not to wait until another one occurs and visit a doctor immediately.
We are dealing with a disorder that causes fear and misunderstanding. This has resulted in stigmatization and discrimination. Therefore, it is best to be well-informed about what it really is and make an effort in order to change stereotypes.
Types and Symptoms
According to theInternational League Against Epilepsy (ILAE), there are three classification levels.
The first one refers to the symptoms of each seizure; the second one to the specific type of the disorder diagnosed depending on the types of seizures. The third level concerns epileptic syndromes and the relationship they may have with other disorders.
In other words, the main types of this disorder are focal seizures, generalized seizures or combined seizures, depending on whether the type of seizure is focal, generalized or a combination of both.
These seizures may include convulsions, but not necessarily. It is refractory when there are recurrent seizures and poor response to treatment, significantly affecting the patient's daily life.
Apart from that, there are epileptic syndromes. In this case, we have to consider the characteristics of the seizure and the specific type as well as other important details such as electroencephalographic activity, age or associated neurological lesions, among other factors.
The following is an explanation of the types of seizures and the types of epileptic syndromes, according to the Spanish Federation of Epilepsy, which also includes the characteristics of childhood epilepsy syndrome.
Focal or Partial Seizures
These are divided into simple, complex or secondary generalization. We are in front of a focal seizure when the following symptoms are presented.
1. Simple Partial
They do not involve loss of consciousness and depending on the exact area of the brain where they originate. These seizures can cause symptoms such as involuntary muscle movements in different parts of the body, uncontrolled laughing or visual, olfactory and auditory hallucinations, as well as strange and unreal thoughts.
2. Complex Partial
In this case, they usuallyinvolve a loss of consciousness during the crisis, but sometimes the person does respond, albeit inconsistently. The most common movements are sucking, swallowing or chewing or there may be excessive rubbing of hands and clothing.
Complex partial seizures can be very confusing because the state of consciousness gradually recovers.
3. Partial with Secondary Generalization
This seizure often precedes a generalized one. That is, even though it starts in a specific area of the brain that only affects some parts of the body, it can spread and affect both hemispheres.
Generalized Seizures
They affect both hemispheres of the brain from the onset of the crisis, making the manifestations visible throughout the body. Generalized seizures diagnose when they include the following subtypes:
1. Generalized tonic-clonic
They are the most common and begin with a stiffness of the extremities that is called the tonic phase. It is followed by the cloning phase, which is characterized by involuntary and rapid muscle movements.
This type of crisis may present head bumps, tongue bites or a lack of sphincter control.
Generalized tonic-clonic seizures are the most widespread picture of the disorder; however, pharmacology has offered several remedies that in most cases make these seizures very unusual. In fact, one of the main triggers is the abrupt withdrawal of medicines.
2. Myoclonic
Their main characteristics include brief, rapid muscle contractions, sometimes occurring in only one limb. This may cause the person to fall or drop objects in their hand.
Diagnosis can be complicated and delayed because the seizures usually last a few seconds and can be confused with a moment of mere clumsiness.
3. Atonic
Involve the sudden loss of muscle tone, which may cause the person to fall to the floor and risk injury. To avoid this situation there are special helmets available.
4. Absence Seizures
They are called "absence seizures" because their main characteristic is the sudden and momentary loss of consciousness followed by recovery. The person usually remains apparently unconscious staring at one spot, unable to respond and therefore the activities s/he is doing at the moment are suddenly interrupted.
These seizures last only a few seconds and the person recovers immediately as if nothing had happened. They are more common in children than adults and are usually confused with attention problems or learning difficulties.
Epileptic Syndromes
The characteristics of the different types depend on the syndrome; they may be childhood idiopathic, idiopathic generalized, reflex, and seizures. However, there are many more subcategories based on comorbidity with other syndromes.
1. Childhood idiopathic
This syndrome is also known as childhood or infant epilepsy because it occurs in children with no apparent cause and when their neurological characteristics are considered appropriate for their age.
It should not be confused with infantile spasms - sudden, rapid movements that usually occur between 3 months and two years of age and gradually decrease in frequency. They tend to contract the extremities, bending and extending arms or knees at high speed.
2. Idiopathic Generalized
They involve unknown, unspecified epilepsies, i.e., without apparent cause, with very similar characteristics to absence or tonic-clonic motor seizures. The medical treatment is usually very favorable.
3. Reflex
External stimuli cause it. It can be a "photosensitive epilepsy", if caused by visual stimuli, or non-photosensitive, when the cause is related to other senses, for instance, the sense of touch.
4. Seizures
The cause is usually an encephalic disease or disorder, and they share symptoms of other syndromes such as West Syndrome (recurrent childhood spasms), Dravet Syndrome, Lennox Gastaut Syndrome or acquired epileptic aphasia.
Causes and Treatments
Fortunately, many advances allow us to identify possible causes such as brain trauma, serious illnesses involving high temperatures, medical records of a severe blow, vascular disorders, or having had a lack of oxygen to the brain at birth or during development.
This disorder has also been linked to neurodegenerative diseases such as Alzheimer, drug use during pregnancy, immune system diseases such as AIDS or meningitis, and finally genetic factors.
The main treatment is the use of anticonvulsant or anti-epileptic medication on a daily basis. These medications prevent seizures and reduce both their frequency and severity. In cases where the person does not respond favorably to this therapy, surgery is usually performed to remove the epileptogenic region.
The problem is that there is a major therapeutic gap: almost 80% of the 50 million people with epilepsy worldwide live in low and middle-income countries. In consequence, it is estimated that about three-quarters of the people with epilepsy will not be able to access the treatment they need.
References
Epilepsy Foundation (2017). Types of Epilepsy Syndromes. Accessed on 28 February, 2018. Available at https://www.epilepsy.com/learn/types-epilepsy-syndromes
Health Line (2018). Everything you need to know about epilepsy. Accessed on 28 February, 2018. Available at https://www.healthline.com/health/epilepsy
Scheffer, I., Berkovic, S., Capovilla, G. et. al. (2017). ILAE classification of the epilepsies: Position paper of the ILAE Commission for Classification and Terminology. Epilepsia Official Journal of the International League Against Epilepsy, 58(4): 512-521
World Health Organization (2017). Epilepsy. Accessed on 28 February, 2018. Available at http://www.who.int/mediacentre/factsheets/fs999/es/