What Is Dravet Syndrome?
Dravet syndrome is an aberrant kind of epilepsy that begins in the child's first year of life. It usually starts with a long-lasting seizure that is greater than five minutes and is brought on by a high fever. Seizures can be of various sorts and severity in children with Dravet syndrome. They also have a variety of additional symptoms, such as developmental delays, speech and language difficulties, as well as balance and walking impairments. Dravet syndrome was formerly known as severe myoclonic epilepsy of infancy, polymorphic epilepsy, and epilepsy with polymorphic seizures.
What Is the Cause of Dravet Syndrome?
In 80 to 90 percent of instances of Dravet syndrome, a mutation is found in the SCN1A gene. Dravet syndrome is likely to be the most severe of a group of illnesses linked to alterations or mutations in sodium ion channel genes. The voltage-gated sodium ion channel is a gated transmembrane protein structure in the cell membrane that regulates sodium ion passage into and out of the cell, allowing electrical signals to propagate along neurons. In excitable cells like neurons and muscle cells, the capacity of a cell to depolarize is crucial because this electrical signal can be used to generate an action potential, which subsequently converts into a response like a neurotransmitter release or contraction. Sodium-ion channels are essential components of any tissue that relies on electrical signals, such as the brain and the heart. Although more than 80 percent of Dravet syndrome patients have a mutation in the SCN1A gene, not all SCN1A mutations cause Dravet syndrome.
What Are the Signs and Symptoms of Dravet Syndrome?
Seizures commonly begin during the first year of life.
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A tonic-clonic seizure, or a seizure involving jerking or clonic motions on one side of the body, is generally the first seizure that occurs with a fever. These seizures are frequently lengthy, last over five minutes, and can lead to status epilepticus. In infancy and early childhood, such seizures usually reoccur every few weeks.
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Myoclonic seizures, which are short shock-like spasms of a muscle or group of muscles, begin between the ages of one to five in 85 percent of children with Dravet syndrome.
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Absence seizures that are not typical.
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Tonic-clonic seizure.
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Seizures with focal awareness or diminished awareness, or partial seizure.
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Atonic seizures.
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Later in childhood, tonic seizures, which occur primarily during sleep, may arise.
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Non-convulsive status epilepticus is characterized by a lack of responsiveness in the kid, as well as eye flutter and body twitching that lasts for long periods of time.
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Seizures can occur without a temperature after the initial febrile seizure. These children, on the other hand, are extremely susceptible to infections and frequently have seizures when they fall sick or have a fever.
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Seizures can also be provoked by minor variations in body temperature that are not caused by infection, such as a hot bath or hot weather.
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Many children suffer from photosensitive seizures that are induced by flashing lights, patterns, or other photic stimuli.
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Seizures can be triggered by excitement or emotional stress in certain children.
In the early years, children usually develop normally. They may miss developmental milestones after the age of two. Other issues that may be encountered include:
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The motor tone is low.
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Walking with trepidation.
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A hunched gait can develop in older children and adults.
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Problems with growth and nutrition.
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Problems with the autonomic nerve system, which controls physiological functions such as the heart, lungs, stomach, and intestines.
How Is Dravet Syndrome Diagnosed?
It might take longer to find out if the child has Dravet syndrome, a rare form of epilepsy because the child's symptoms may resemble those of other diseases found in childhood, and one can get the wrong diagnosis at first. It is absolutely critical to get a correct diagnosis. Giving a kid with Dravet syndrome medications to manage other issues, such as febrile seizures, may exacerbate their symptoms. If the kid has had two or more seizures lasting several minutes each before the age of one, see a doctor or a pediatric neurologist, especially if the seizures were induced by heat. Dravet syndrome is diagnosed using a combination of symptoms and test results.
Symptoms that aid in the diagnosis of Dravet syndrome include:
Seizures are the most common symptom in infants. Some seizures are referred to as "tonic-clonic." The child's muscles will stiffen, and they may pass out during this type of seizure. The other sort of seizure is called "hemiclonic", and it occurs when a baby's arm or leg jerks violently on one side of the body. Seizures are frequently triggered by heat. A warm bath, being outside in warm temperatures, or an illness could cause the infant to have seizures. Each seizure might last anywhere from 5 to 15 minutes. Seizures may become less frequent and last for less time as the child grows older. Seizures can sometimes occur without being triggered by heat.
Other symptoms:
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Learning at a slower pace.
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Problems with balance and a wobbly gait.
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Muscle tone is low.
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Language and speech are delayed.
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Nutritional issues and slow growth.
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Sleeping problems.
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Infections that recur.
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Heart rate, blood pressure, and body temperature are difficult to control.
Magnetic Resonance Imaging (MRI): It is a type of imaging that uses a magnetic field and radio waves to provide extremely detailed images of the child's brain. This test can assist doctors in determining the source of seizures. To keep babies and young children calm during the exam, they may need to be sedated.
Electroencephalogram (EEG): It is one of the most frequent tests used by doctors to determine the origin of seizures. It detects the pattern of electrical impulses that occur when brain cells communicate with one another.
Genetic Tests: These can help parents figure out if the child has Dravet syndrome or not. The SCN1A gene has a mutation in about 90 % of children with the disease, and this gene aids in the transmission and reception of electrical signals by brain cells. A blood test is used to check for the SCN1A gene and other genetic alterations associated with Dravet syndrome.
What Is the Treatment for Dravet Syndrome?
The aim of treatment is to curtail the child's seizure frequency and severity because seizures vary in type and duration, and no two children will have the same response to treatment.
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Medications: Dravet syndrome patients have seizures that are hard to control. The objective of seizure treatment is to determine the most effective pharmaceutical combination for the child's long-term condition. To treat the various seizure types found with Dravet syndrome, two or more drugs are usually required. Some anti-seizure drugs can aggravate seizures and should not be used.
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Diet: According to research, the ketogenic diet is beneficial. Individuals with Dravet syndrome may benefit from food that is heavy in fat and low in carbohydrates. Diet has an impact on metabolic pathways involved in central nervous system function. This diet is rich in fat, low in carbohydrates, and adequate in protein. A ketogenic diet is a diet meant to assist youngsters with epilepsy in managing their symptoms. When drugs have failed to control the child's seizures, this treatment is usually considered a last resort.
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Vagus Nerve Stimulator: A vagal nerve stimulator is an implantable device that is implanted under the child's skin in the chest. It delivers an electrical impulse to the child's vagus nerve. The impulse balances out their brain's aberrant electrical activity, which triggers seizures. Every few minutes, a wire attached to the stimulator sends energy pulses to the brain through the vagus nerve in the neck. When the child feels a seizure initiating, they can place a magnet over the battery and send a signal. Often, this will bring the seizure to a halt.
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Additional Therapies: Dravet syndrome can impact a child's capacity to think, speak, move, and learn. Before starting school, the doctor may suggest that the kid undergo a developmental evaluation. Children with this illness can benefit from a mix of physical therapy, occupational therapy, and speech therapy to keep on track with their peers. Children are taught exercises to increase their strength, mobility, and coordination by physical therapists. Occupational therapists teach children how to execute everyday tasks like buttoning their garments and picking items up in a more efficient manner. Speech therapists diagnose and treat language and speech disorders.
Conclusion
The chance of sudden, unexpected mortality is higher in people with Dravet syndrome than in the general population. Seizures may be long-lasting and frequent in the child. The goal of seizure treatment is to achieve the most excellent feasible seizure control. Medications can help lower the number and severity of seizures, but seizure-free living is rarely attainable. Other health issues and developmental setbacks will arise in the child, which must be identified and treated as soon as possible. With growing age, a hunched gait is noticed. Seizures tend to get fewer and milder as the child gets older. Despite this, the majority of children, teenagers, and adults require continuing parental or caregiver care.
