In infantile spasms, children suddenly raise and bend their arms, bend their neck and upper body forward, and straighten their legs.
Many children who have infantile spasms also develop abnormally or have intellectual disability.
Electroencephalography is done to diagnose the disorder, and analysis of samples of blood, urine, and the fluid around the spinal cord as well as brain imaging helps doctors identify the cause.
Injecting adrenocorticotropic hormone into a muscle or giving a corticosteroid or vigabatrin (an anticonvulsant) by mouth often helps control the spasms.
Infantile spasms are a type of seizure. A seizure is an abnormal, unregulated electrical discharge that occurs within the brain and temporarily interrupts normal brain function.
Infantile spasms last for only a few seconds but typically occur close together in a series that lasts several minutes. Children may have many series of spasms a day. Spasms usually start when children are younger than 1 year. They may stop by age 5 years, but often, another type of seizure then develops.
Usually, infantile spasms occur in infants who have a serious brain disorder or developmental problem, which may have already been diagnosed. These disorders include
Tuberous sclerosis, a hereditary disorder, is a relatively common cause of infantile spasms. People with this disorder have long, narrow growths in the brain, which resemble roots or tubers.
Sometimes no cause can be identified.
Spasms usually consist of a sudden jerk (spasm) of the trunk and limbs. Sometimes the spasms involve only slight nodding of the head. Spasms may last several seconds, and children usually have many spasms in clusters, one right after the other.
Spasms typically occur soon after children wake up and rarely occur during sleep.
In most affected children, intellectual development, including development of language skills, is slow, and intellectual disability is present. When infantile spasms start, children may at least temporarily stop smiling or lose developmental skills that they have learned, such as being able to sit up or roll over.
Doctors diagnose infantile spasms based on symptoms and results of electroencephalography (EEG), which is done to check for specific patterns of abnormal electrical activity in the brain. EEG is done while children are sleeping and while they are awake.
Other tests are done to look for the cause:
Magnetic resonance imaging (MRI) of the brain is done to look for signs of brain damage or malformations.
Samples of blood, urine, and the fluid around the spinal cord (cerebrospinal fluid) may be analyzed to check for disorders that may be causing the spasms, such as metabolic disorders. Cerebrospinal fluid is obtained by doing a spinal tap (lumbar puncture).
If the diagnosis is still unclear, genetic tests may be done.
Because early control of infantile spasms is associated with a better developmental outcome, early identification and treatment of spasms are essential.
The most effective treatment for infantile spasms is adrenocorticotropic hormone (ACTH), injected into a muscle once a day. A corticosteroid (such as prednisone), given by mouth, may also be effective.
The only other drug that has been clearly proven to help stop the spasms is the anticonvulsant vigabatrin. It is particularly helpful when tuberous sclerosis is the cause. There is insufficient evidence that any other anticonvulsant or a ketogenic diet is effective.
Sometimes epilepsy surgery is done to eliminate the cause of the spasms. An area of the brain may be surgically removed if seizures are caused by only that one area and that area can be removed without significantly affecting the child's ability to function.