The Causes of Epilepsy

"Why?" is perhaps the question you ask most often. In this chapter, we will look at the main known causes of epilepsy, along with the classification your doctor uses. Let us say at the outset: despite every effort, in a significant portion of children no clear cause is found — and this is not necessarily bad news.

The Six Main Groups of Causes of Epilepsy

The International League Against Epilepsy (ILAE) groups the causes of epilepsy under six main headings. A child may have more than one cause at the same time. These groups are:

1. Structural Causes

There is a difference or damage in the structure of the brain that can be seen with imaging methods (especially MRI). Examples include congenital differences in brain development (such as cortical dysplasia), damage from lack of oxygen occurring during or before birth, past brain hemorrhages, trauma, tumors, or vascular differences.

2. Genetic Causes

Epilepsy may be caused directly by a genetic change. This does not necessarily mean the condition was passed down from the family; the genetic change may have arisen for the first time in the child (de novo). Some genetic epilepsies have a good outlook (for example, some childhood absence epilepsies), while others can lead to more severe conditions (for example, Dravet syndrome).

3. Infectious Causes

One of the most common causes of epilepsy worldwide is past infections of the central nervous system. Infections such as meningitis (inflammation of the membranes around the brain) and encephalitis (inflammation of the brain) can set the stage for epilepsy even after they have healed.

4. Metabolic Causes

Some inborn disorders in the body's chemical processes (metabolism) can affect brain function and lead to seizures. Some of these causes are important because a few of them can be directly corrected with a special diet or vitamin treatment.

5. Immune Causes

In some cases, the body's immune system mistakenly attacks the brain's own tissue (as in autoimmune encephalitis). These types of epilepsy are a relatively newly recognized group and may respond to treatments that suppress the immune system.

6. Unknown Causes

Despite all modern tests, in a significant portion of children the cause of epilepsy cannot be found. This group is called "of unknown cause." This phrase does not mean the doctor did not investigate enough; it simply means the cause has not yet been identified with today's knowledge and technology. As science advances, a cause can eventually be found in some of this group.

Is "No Cause Found" Bad News?

No. On the contrary, epilepsies with no identifiable cause are often not linked to structural damage and may therefore have a better outlook.

What matters is bringing the seizures under control and keeping the child's development on a healthy track. Even when the cause is not always known, treatment is usually possible.

Factors That Trigger Seizures

It is important to distinguish the "cause" of epilepsy from the factors that "trigger" seizures. The cause is the underlying condition behind the epilepsy; a trigger is a factor that, in a child who has epilepsy, temporarily lowers the seizure threshold and makes a seizure more likely. The most common triggers are:

• Lack of sleep and irregular sleep (one of the most common and most important triggers).
• Fever and infections.
• Taking medications irregularly or skipping doses.
• Excessive stress, fatigue, and emotional ups and downs.
• Flashing lights in some children (photosensitivity) — but, contrary to popular belief, this affects only a small portion of children with epilepsy.
• Alcohol and sleepless nights in adolescents.

Getting to know your child's triggers is one of the most practical ways to reduce seizures. The seizure diary we will introduce in the next section will help you discover exactly these triggers.

A Practical Way to Discover Triggers

Each child's triggers can be different, and sometimes no clear trigger is found. The best way to discover your child's specific triggers is to keep a seizure diary. When a seizure happens, think back over the previous 24 hours: Did the child sleep well? Were they sick or feverish? Did they experience unusual stress? Was there a delay in the medication schedule? Over time, the notes in your diary may reveal a pattern, and knowing that pattern is one of the most practical ways to reduce seizures.

But there is an important balance to keep in mind: managing triggers should not mean cutting the child off from life. For example, paying attention to sleep is reasonable, but keeping a child away from every excitement and every activity is excessive and harmful. The goal is to reduce risk with reasonable precautions while allowing the child to live a full life.

Why Does "Finding the Cause" Sometimes Take Time?

In some families, the diagnostic process can take a long time, and this requires patience. The reason is that epilepsy has hundreds of different causes, and some of them only come to light with advanced tests. Also, some findings become clearer over time, as the child's development is followed. Each test done while searching for the cause is actually one step closer to the right answer, ruling out one possibility at a time. Trusting your doctor during this process and asking your questions openly will both reassure you and speed things up.