Infantile spasm(West syndrome): Symptoms, Diagnosis & Treatments
Epidemiology & Symptoms
Infantile spasm (West syndrome) usually occurs between 2 and 12 months. It is known that around one in 3,000 people worldwide suffer from this disease. Infantile spasms are characterized by three distinct patterns: the epileptic syndrome, which is a key factor in distinguishing the disease from other epileptic syndromes.
The first is an epileptic spasm that appears cluster-like shortly after sleeping just before going to bed. The second is developmental regression and the third is a typical EEG pattern called hypsarrhythmia.
Hypsarrhythmia is a characteristic pattern that appears on the EEG. It refers to the appearance of an irregular, multi-focal high-voltage spike on the chaotic slow background as shown above.
In the case of Cryptogenic West syndrome, the child undergoes normal development before the seizure is expressed. In the case of symptomatic west syndrome, the child suffers from developmental disturbance preceding seizure, which is caused by peri-natal encephalopathy, malformation, and underlying metabolic disorder. Cryptogenic west syndrome is more susceptible to diagnosis than symptomatic west syndrome because structural normal metabolic abnormalities are not observed and normal development process precedes seizure expression. West syndrome is thought to be a medical emergency because cryptogenic west syndrome may have a great impact on the prognosis in patients with delayed diagnosis for more than 3 weeks.
Diagnosis
For diagnosis, you should first make sure that there are no special events in the peri-natal period and that there are no impediments to development before symptoms develop. In all cases, we need to look for abnormal EEG patterns such as hypsarrhythmia by analyzing EEG recorded before sleep and after sleep. The most important diagnostic value is neuro-imaging. It is known that neuroimaging can reveal about 70% of etiology in symptomatic west syndrome. MRI is mainly used as a neuro-imaging tool. In addition, genetic testing and metabolic screening may be helpful in diagnosis.
Treatments
In the infant stage, the density of corticotropin-releasing hormone (CRH) receptors is so high that CROH-induced stress reactions are over-induced and neurons are thought to be excited and trigger seizures. Therefore, ACTH or steroids that inhibit CRH are used for treatment. If infantile spasms are caused by tuberous sclerosis, vigabatrin may be effective. If these drugs are not heard, second-line treatment with benzodiazepines, valproic acid, lamotrigine, topiramate, zonisamide, and levetiracetam can be used. Ketogenic diets may be used, but side effects such as GI disturbance, infection, and renal stone may be present.
West syndrome in boys may be associated with ARX gene mutations, which are often accompanied by ambiguous genitalia and cortical migration abnormalities. In girls, there may be CKL5 / STK9 mutations.
Infantile spasm (West syndrome) usually occurs between 2 and 12 months. It is known that around one in 3,000 people worldwide suffer from this disease. Infantile spasms are characterized by three distinct patterns: the epileptic syndrome, which is a key factor in distinguishing the disease from other epileptic syndromes.
The first is an epileptic spasm that appears cluster-like shortly after sleeping just before going to bed. The second is developmental regression and the third is a typical EEG pattern called hypsarrhythmia.
Hypsarrhythmia is a characteristic pattern that appears on the EEG. It refers to the appearance of an irregular, multi-focal high-voltage spike on the chaotic slow background as shown above.
In the case of Cryptogenic West syndrome, the child undergoes normal development before the seizure is expressed. In the case of symptomatic west syndrome, the child suffers from developmental disturbance preceding seizure, which is caused by peri-natal encephalopathy, malformation, and underlying metabolic disorder. Cryptogenic west syndrome is more susceptible to diagnosis than symptomatic west syndrome because structural normal metabolic abnormalities are not observed and normal development process precedes seizure expression. West syndrome is thought to be a medical emergency because cryptogenic west syndrome may have a great impact on the prognosis in patients with delayed diagnosis for more than 3 weeks.
Diagnosis
For diagnosis, you should first make sure that there are no special events in the peri-natal period and that there are no impediments to development before symptoms develop. In all cases, we need to look for abnormal EEG patterns such as hypsarrhythmia by analyzing EEG recorded before sleep and after sleep. The most important diagnostic value is neuro-imaging. It is known that neuroimaging can reveal about 70% of etiology in symptomatic west syndrome. MRI is mainly used as a neuro-imaging tool. In addition, genetic testing and metabolic screening may be helpful in diagnosis.
Treatments
In the infant stage, the density of corticotropin-releasing hormone (CRH) receptors is so high that CROH-induced stress reactions are over-induced and neurons are thought to be excited and trigger seizures. Therefore, ACTH or steroids that inhibit CRH are used for treatment. If infantile spasms are caused by tuberous sclerosis, vigabatrin may be effective. If these drugs are not heard, second-line treatment with benzodiazepines, valproic acid, lamotrigine, topiramate, zonisamide, and levetiracetam can be used. Ketogenic diets may be used, but side effects such as GI disturbance, infection, and renal stone may be present.
West syndrome in boys may be associated with ARX gene mutations, which are often accompanied by ambiguous genitalia and cortical migration abnormalities. In girls, there may be CKL5 / STK9 mutations.
