The brain is composed of neurons, tiny cells that communicate with each other through electrical signals. A seizure is a sudden abnormal discharge of electrical signals in the brain that impairs the normal function of the brain. According to the Children’s Hospital of Boston, 3 to 5 percent of all children can experience a seizure, particularly before their first birthday. There are several causes of seizures in young children.
Fever
Febrile seizures are the most common type of seizures in young children. According to the National Institute of Neurological Disorders and Stroke, these seizures affect approximately one in every 25 children, and more than one-third of them will have repeated episodes of febrile seizures.
The cause of febrile seizures is a sudden increase in the child’s baseline body temperature. The temperature suddenly increases, leading to a generalized involuntary shaking of arms and legs, accompanied by loss of consciousness. These seizures are usually brief, lasting less than five minutes, and are not harmful to the child. No treatment is needed for a first time febrile seizure. A child with repeated episodes of febrile seizures may need anti-epileptic drugs to control them.
Infections
Infections of the brain and the central nervous system are another common cause of seizures in young children. Meningitis is an inflammation of the meninges, the tissue covering the brain. The most common causes in children include bacteria and viruses. Children with meningitis can present with fever, irritability, headaches, fear of bright lights, or photophobia, and seizures.
Encephalitis is an inflammation of the brain itself, mostly caused by viruses. It can present in the same way as meningitis, with the added symptoms of altered mental status such as loss of consciousness and confusion. Seizures in these conditions result from irritation of the brain tissue and the neurons by the microorganisms themselves or by the byproducts of the body’s response to inflammation.
Electrolyte Imbalances
Electrolytes are molecules in the body that carry an electrical charge. Common electrolytes include sodium, potassium and calcium. An imbalance in the level of some of these electrolytes can lead to seizures. For example, syndrome of inappropriate secretion of ADH, or SIADH, is a known complication of meningitis in which the brain secretes too much ADH—a hormone that regulates fluid absorption from the kidneys. It can cause a decrease in the levels of sodium in the blood and seizures. Likewise, high sodium can cause seizures, especially if it is corrected too quickly.
