Medical history of pediatric epilepsy
The personal history of childhood epilepsy should include the presence of infection, preterm abortion, and other discomfort during the mother’s pregnancy. Attention should be paid to all larger events at birth and early in the child’s development, such as whether the child was born at full term, with or without asphyxia, birth injuries, intracranial hemorrhage, severe jaundice, intracranial infection, encephalitis, meningitis; any severe head trauma, any high fever convulsions, and any poisoning. The presence of any special hazards (both physical and emotional) suffered before the convulsions, the presence of fever, ear infections, central nervous system infections and other potential causes, and the intelligence of the child. These are important clues to the etiologic diagnosis and treatment.
Etiology of pediatric epilepsy
Although the etiology of pediatric epilepsy is complex, with the rapid development of medical technology, most of the causes have been clearly understood and, in general, epilepsy can be classified into two main categories etiologically:
Epilepsy without a clear cause
This category accounts for 20% of all epilepsy patients and is mostly genetically related, so it is also called cryptogenic epilepsy or hereditary epilepsy.
Epilepsy with a definite cause
The most common causes include.
(i) congenital brain developmental malformations: such as anencephaly, giant gyrus malformation, polymicrocephaly, gray matter heterotopia, cerebral penetration malformation, congenital hydrocephalus, hydrazine hypoplasia, arachnoid cysts, microcephaly, and macrocephaly.
(ii) Neurocutaneous syndromes: the most common ones are tuberous sclerosis, neurofibromatosis and cerebral trigeminal angiomatosis, etc.
(iii) genetic metabolic diseases: such as phenylketonuria, hyperammonemia, cerebral lipid deposition disorder, vitamin B6-dependent disorder, etc.
(iv) Perinatal brain injury: mainly birth injury, asphyxia, intracranial hemorrhage, hypoxia, ischemic encephalopathy, of which hypoxic-ischemic encephalopathy resulting in epilepsy is the most common.
⑤ intracranial infections: such as bacterial meningitis, viral encephalitis, brain abscess, mycobacterial meningitis, cerebral parasitosis, post-inoculation encephalitis, and post-infectious encephalitis
(vi) Nutritional metabolic disorders and endocrine diseases: common hypoglycemia, hypocalcemia, hypomagnesemia, vitamin B6 deficiency, and hypothyroidism.
(vii) Cerebrovascular disease: such as cerebrovascular malformation, intracranial hemorrhage, cerebrovascular inflammation, cerebral infarction.
(viii) Trauma: intracranial hemorrhage, skull fractures, and cerebral contusions caused by trauma can cause epilepsy, but the incidence is related to the degree and location of the injury.
⑨ Brain injury after febrile convulsions also leads to epilepsy.
Characteristics of pediatric epilepsy
Pediatric epilepsy has a high incidence and serious health consequences. Because of the physiological characteristics of newborns and the neurological and humoral changes, pediatric epilepsy has many unique clinical features compared to adults.
(1) Genetic factors: It is now recognized that epilepsy is associated with genetics and has a greater impact on childhood epilepsy. This is demonstrated by the fact that not only is epilepsy itself genetically predisposed, but also for some other genetic disorders, epileptic symptoms are often seen and may even be the main symptom, such as phenylketonuria, neurofibromatosis, and tuberous sclerosis. Clinical data demonstrate that children with a genetic predisposition to epilepsy can have seizures when exposed to a variety of general and minor external factors. Even if no clinically significant seizures are present, there can be evidence of a lowered seizure threshold, i.e., spike-wave or multi-spike slow-wave discharges on the EEG.
(2) Acquired factors: i.e., there are epileptic pathological changes in the brain, and these acquired brain injuries cause structural or metabolic lesions in the brain that produce epileptic foci; the lesions can be diffuse or limited, resting or progressive. There are many causes of brain injury, but in pediatric patients it is mostly congenital developmental abnormalities, birth or trauma, brain infections, and febrile convulsions.
(3) Gender, age of onset and seizure type: generally more males than females, most often in young children, and there is a close relationship between age and seizure type. Neonatal seizures are often insidious and focal, while older children have obvious and generalized convulsions.
(4) Seizure manifestations: The incidence of each seizure type varies with age, and its clinical manifestations are closely related to the maturity of the central nervous system. In addition to the common grand mal seizures that occur at any age in children, the clinical manifestations of neonatal epilepsy are mostly in the form of stereotyped repetitive movements and are often accompanied by abnormal eye movements.
(5) Intellectual alterations: Anyone with obvious organic, genetic, or metabolic brain etiology, as well as those with abnormal neurological signs, almost always has low intelligence. The younger the age, the higher the incidence of intellectual impairment, and the different seizure types with intellectual decline, from high to low, in order of infantile spasms, disorientation seizures, and the more frequent the seizures, the higher the rate of low intelligence, severe seizures itself can affect intellectual development.
In addition, pediatric epilepsy is characterized by the diversity and variability of seizures in the same patient and the ease of triggering by adverse factors.
Effects of epilepsy on the intelligence of the child
Intellectual abnormalities play an important role in childhood epilepsy. The use of IQ tests during follow-up is important for early detection of children with low IQ, early intervention, and timely treatment. The following factors affecting the intelligence of children with epilepsy should be taken into account.
Primary epilepsy generally has a good prognosis, with complete seizure control with medication and a higher IQ than secondary epilepsy. In addition to biological factors, there are also social factors that cause low IQ in children with primary epilepsy, as children with primary epilepsy often have fear and anxiety and are unable to stay in school, resulting in low IQ.
Medications: Some antiepileptic drugs have an effect on intelligence, such as phenobarbital, sodium phenytoin, sodium valproate, and benzodiazepine antiepileptic drugs can impair memory, motor speed, and mental development, which can cause mental retardation if taken for a long time.
Congenital and acquired: Some congenital factors such as craniosynostosis, genetic and metabolic defects are common causes of epilepsy and mental retardation, which are difficult to treat and serious. Among the postnatal factors, low IQ is related to the severity of central nervous system infection and the presence of complications. Therefore, febrile convulsions in infancy should be actively managed and prevented, and should be controlled with drugs immediately to avoid permanent brain damage after convulsions.
Age: Infants and toddlers with seizures are more likely to have low IQ than older children, with more severe seizures at younger ages and more mild seizures at older ages. This is related to the characteristics of brain development in infants and young children, because the metabolism of brain tissue is active during infancy, and cell differentiation and myelin formation are vigorous, so they are most likely to suffer from convulsive brain injury. The younger the age of onset, the earlier the onset, the more obvious the low IQ.
The type of seizure: clinical seizure type is closely related to intelligence, and the intelligence of children with different types of epilepsy varies. Complex partial seizures have a greater impact on IQ, while simple partial seizures have a smaller impact. Infantile spasms and small motor seizures are difficult to treat and have low IQ, while petit mal seizures have a better prognosis. The duration of seizures, the frequency of seizures, the control of symptoms, and the regularity and timeliness of treatment are closely related to intelligence.
In conclusion, early diagnosis of pediatric epilepsy, determination of seizure type, timely and reasonable medication, and elimination of the cause are the keys to prevent mental retardation and prognosis. The prognosis is not only related to the degree of seizure control, but also to the social or psychological adaptation. In addition to the use of appropriate antiepileptic drugs, the child’s family should be counseled on the treatment of childhood epilepsy, and the child’s intelligence should be followed up to improve the IQ level of the child.