Infantile Spasms (IS), also known as West Syndrome, is a rare form of age-specific epilepsy that usually presents itself in children within the first year of life. Early diagnosis and treatment of Infantile Spasms is of the utmost importance, and in many cases can ensure a more positive prognosis and a better quality of life, and significantly increases the chances of achieving reaching normal child development milestones.
Watch the videos below and check out our blog to hear a firsthand account of what it’s like to have a child with Infantile Spasms and to learn more about how Infantile Spasms (IS) are diagnosed, what signs to look for and what treatments are available.
In honor of Infantile Spasms Awareness Week, please share the videos below with friends and family in order to help us raise awareness about this rare form of epilepsy, and about the importance of early diagnosis and treatment.
– The overall intellectual and neurodevelopmental outcome in children with infantile spasms is generally poor
– The long-term prognosis is directly related to the underlying cause of the seizures
– Better developmental outcomes are noted in patients without an identified cause (cryptogenic/idiopathic)
– Although the spasms tend to resolve by early to mid childhood, a majority of the children develop other types of seizures and epilepsies.
– There is a better outcome noted in those patients treated earlier in the course of their seizures, and in those that have an early and sustained response to treatment.
The long-term prognosis of patients with infantile spasms has been studied extensively over the years. Many studies have examined the outcome of infantile spasms including neurodevelopmental and intellectual disabilities, prognostic significance of the EEG, and the development of chronic epilepsy.
The consensus of all of these studies is that the overall outcome, with regards to chronic epilepsy and neurodevelopmental disability is generally poor in patients with infantile spasms.
Epileptic spasms usually resolve, latest by mid-childhood, in the majority of patients. Infrequently, spasms may persist in adulthood. Even if the spasms resolve, it has been found that 50-70% of the patients will develop other seizure types. Approximately 50% of the patients with a history of infantile spasms go on to develop chronic intractable epilepsy. There is a strong relationship seen between a history of infantile spasms (IS) and development of Lennox- Gastaut syndrome, with 18-50% of IS patients developing Lennox-Gastaut syndrome.
While features of hypsarrhythmia define the EEG of patients with infantile spasms, evidence of this abnormality on the first EEG was seen not to influence the response to treatment. However, if the hypsarrhythmia persisted despite treatment, or was atypical and/or asymmetrical, this was seen to adversely influence the long-term outcome.
The most important factor in predicting the cognitive and developmental outcome of patients is etiology.
Mental retardation occurs in about 70 % of patients with infantile spasms, usually involving severe to profound retardation and often associated with other psychiatric problems. Other neurological deficits, such as cerebral palsy, may be seen in about 30-50% of patients.
Most children with infantile spasms experience slowing, plateauing, or regression of their developmental progress.
Studies have consistently shown that infants with symptomatic infantile spasms are at much higher risk (86-90%) of developing mental retardation, autism and other behavioral and cognitive disabilities, compared to infants with idiopathic infantile spasms. Symptomatic infantile spasms, in particular, are associated with autism spectrum disorders (ASD) in up to 35% of cases.
10-20% of patients with normal development prior to the start of their spasms will have normal mental function or only be mildly impaired long-term. 28-50% of patients with idiopathic infantile spasms will go on to have normal or borderline cognitive development.
The premature death rate for infantile spasm ranges from 5-31%. Most of the deaths (61%) occurred at or before age 3 years, while only 10% occurred after age 20 years.
In most cases, the mortality is seen to be a result of the underlying neurological cause of the infantile spasms.
Factors for a favorable outcome in Infantile Spasms
• Cryptogenic or idiopathic cause
• Age of onset of spasms > 4 months
• No atypical or partial seizures
• Typical EEG abnormalities – hypsarrhythmia
• Early onset of treatment
• Early and good response to treatment
Infantile spasms is a potentially devastating early-onset epilepsy that affects infants, typically between three and nine months of age. Many cases of infantile spasms occur in children who are already have brain abnormalities, such as children with tuberous sclerosis, down syndrome, or brain injuries sustained as newborns. However, in about one third of affected infants, infantile spasms occur for no known reason.
There are three first-line treatments used for infantile spasms. Most pediatric neurologists select one of these three as the initial treatment.
First, adrenocorticotropic hormone (ACTH) is a naturally occurring hormone that is made by the pituitary gland. It stimulates the body to produce steroids. There are several versions of ACTH available throughout the world — in the US, physicians can prescribe a pharmaceutical grade purified ACTH for infantile spasms. ACTH must be given by injection into the infant’s thigh twice a day for two weeks, and then gradually tapered over the next several weeks. There are significant side effects. Many babies become very irritable when taking this medication. It increases their appetite, and some gain weight during treatment. ACTH can also increase blood pressure and, on occasion, lead to an increase in the size of the heart. These side effects fade after the medication is stopped.
Second, oral prednisolone is a corticosteroid, which comes as a liquid. This is the same medicine given for children with asthma attacks; although, for infantile spasms we use a higher dose for a longer period of time (usually several weeks). It can have the same side effects as ACTH, but these are usually less severe.
Third, vigabatrin is a medication that comes as a packet of powder, which can be disolved in water. The major worrisome side effect of vigabatrin is loss of peripheral vision. This is uncommon. Usually when vigabatrin is prescribed, the infant will also need to see an ophthalmologist to monitor for this potential side effect.
Current evidence suggests that ACTH has the best overall response rate. The one exception is that for children who have infantile spasms due to tuberous sclerosis, vigabatrin seems to work better.
First-line therapy works between half and three quarters of the time. If it fails, there is not good evidence to guide us on what to try next. Many physicians will switch to a different first-line agent. For example, if a child continues to have seizures after ACTH, the physician may try vigabatrin next. Rarely, a deficiency of vitamin B6 can cause infantile spasms, and many physicians will give infants this vitamin. Other physicians may try dietary therapy. For example, there is a diet called “the ketogenic diet” that avoids carbohydrates and sugars. This diet can lead to changes in how the brain makes fuel for itself, which can, in turn, reduce seizures.
In some cases, children with infantile spasms may have a subtle area of the brain which is abnormal, which is difficult to see on MRI scans. Some physicians will order other kinds of brain scans, such as a PET scan (positron emision tomography), in order to look for these kinds of abnormalities. This is important, because some infants benefit from epilepsy surgery to remove the abnormal area of brain.
Dr. Zachary Grinspan, MD