The spasms are usually caused by serious brain disorders.
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 help doctors identify the cause.
Injecting adrenocorticotropic hormone into a muscle or giving a corticosteroid or vigabatrin (an antiseizure drug) by mouth often helps control the spasms.
Infantile spasms are a type of seizure Seizures in Children Seizures are a periodic disturbance of the brain’s electrical activity, resulting in some degree of temporary brain dysfunction. When older infants or young children have seizures, they often... read more . 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 of age. They may stop by 5 years of age, but often, another type of seizure then develops.
Causes of Infantile Spasms
Usually, infantile spasms occur in infants who have a serious brain disorder or developmental problem, which may have already been diagnosed. These disorders include
Metabolic disorders Overview of Hereditary Metabolic Disorders Hereditary metabolic disorders are inherited genetic conditions that cause metabolism problems. Heredity is the passing of genes from one generation to the next. Children inherit their parents'... read more (problems that affect body chemistry) or genetic disorders Overview of Chromosome and Gene Disorders Chromosomes are structures within cells that contain a person's genes. A gene is a segment of deoxyribonucleic acid (DNA) and contains the code for a specific protein that functions in one or... read more
Lack of oxygen in newborns, as may occur during labor or delivery
Sometimes a serious head injury in infants (either during or after birth)
Tuberous sclerosis complex Tuberous Sclerosis Complex Tuberous sclerosis complex is a hereditary disorder that causes abnormal growths in the brain, changes in the skin, and sometimes tumors in vital organs, such as the heart, kidneys, and lungs... read more , 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 of infantile spasms can be identified.
Symptoms of Infantile Spasms
Spasms usually consist of a sudden jerk (spasm) of the trunk and limbs that looks very much like the infant has startled. 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 occasionally occur during sleep.
In most affected children, intellectual development, including development of language skills, is slow, and intellectual disability Intellectual Disability Intellectual disability is significantly below average intellectual functioning present from birth or early infancy, causing limitations in the ability to conduct normal activities of daily... read more 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.
Diagnosis of Infantile Spasms
Magnetic resonance imaging
Sometimes blood and urine tests and a spinal tap
Doctors diagnose infantile spasms based on symptoms and results of electroencephalography (EEG) Electroencephalography Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Electroencephalography (EEG) is a simple, painless procedure in which... read more , 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.
Magnetic resonance imaging (MRI) Magnetic Resonance Imaging (MRI) In magnetic resonance imaging (MRI), a strong magnetic field and very high frequency radio waves are used to produce highly detailed images. MRI does not use x-rays and is usually very safe... read more of the brain is done to look for signs of brain damage or malformations.
Other tests are done to look for the cause:
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 Spinal Tap Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Electroencephalography (EEG) is a simple, painless procedure in which... read more (lumbar puncture).
If the cause of infantile spasms is still unclear, genetic tests may be done.
Treatment of Infantile Spasms
Vigabatrin (an antiseizure drug)
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. ACTH therapy is typically continued for 2 to 3 weeks and then tapered off over 6 to 9 weeks. A corticosteroid (such as prednisone), given by mouth, may also be effective as an alternative to ACTH.
Vigabatrin is an antiseizure drug given by mouth. It is the drug of choice when tuberous sclerosis complex is the cause of the spasms. There is not enough evidence to support that any other antiseizure drug or a ketogenic diet is effective.
Sometimes epilepsy surgery Surgery In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before... read more 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.