Some of the symptoms of infantile spasms include involuntary muscle spasm in the trunk, neck and head; delays in acquiring skills in infants; and recurrent epileptic seizures as the child ages, explains the National Organization for Rare Disorders. In general, the condition is characterized by onset of spasm, sometimes mental retardation and abnormal brain wave patterns.
Symptoms associated with infantile spasms usually begin in the first year of life, explains the National Organization for Rare Diseases.The involuntary muscle spasms occur due to uncontrolled electrical disturbances in the brain. Each involuntary spasm begins abruptly and continues for just a few seconds, and the spasms usually occur in clusters that can last 10 to 20 minutes. These episodes may present after feeding or awakening, with the duration and intensity affected by the seizures varying from one infant to another.
The cause of infantile spasms can be identified in about 70 to 75 percent of those affected, explains the National Organization for Rare Diseases.The underlying cause is any disorder that leads to brain damage, including brain malformations such as cortical dysplasia, chromosomal abnormalities, infections and trauma. The most common disorder responsible for infantile spasms is tuberous sclerosis complex, an autosomal dominant genetic condition associated with seizures, and kidney and heart tumors.