Epilepsy (epilepsy): is a chronic brain disorder characterized by the persistence of persistent brain changes capable of producing seizures with corresponding neurobiological, cognitive, psychological, and social consequences [1]. Generally, epilepsy is diagnosed when two clinical occurrences (at least 24 hours apart) of nonprovoked seizures occur. In 2005, the International League Against Epilepsy (ILAE) revised the definition of epilepsy and stated that “a single seizure may be required for the diagnosis of epilepsy in the presence of a persistent epileptogenic tendency in the brain” [2]. This definition has positive implications for the early diagnosis and treatment of epilepsy, but it lacks clinical applicability due to the difficulty of determining the risk of recurrence after an individual’s first seizure in most cases. Provoked seizures are most commonly seen in the acute phase of certain diseases; for example, seizures occurring in the acute phase of central nervous system infections (viral encephalitis) or systemic systemic diseases (hypoglycemia/electrolyte disturbances/fever, etc.) are provoked seizures. Non-provoked seizures do not have a clear acute trigger
An epileptic seizure is a sudden, transient clinical manifestation caused by abnormal excessive, synchronized neuronal firing activity in the brain, depending on the functional areas of the brain involved. Seizures are different from epilepsy in that seizures are a symptom that can be seen in some acute brain dysfunction, such as central nervous system infections, in addition to epileptic patients, whereas epilepsy is a chronic brain disorder with recurrent seizures as the main manifestation. Seizures are classified as convulsive (convulsion) and non-convulsive. Convulsive seizures are accompanied by muscle contractions such as tonic-clonic seizures, and nonconvulsive seizures are not accompanied by muscle contractions such as typical or atypical akathisia.
Epilepsy is a common neurological disorder in children and the annual incidence of epilepsy in China is 35/100,000 population with a prevalence rate of 4-7 per 100,000, with about 60% starting in childhood [3]. With the continuous development of clinical and EEG, imaging, molecular genetics and antiepileptic drugs, the diagnosis and treatment of epilepsy have been improved, and 70-80% of children with epilepsy can be completely controlled, and most of them can live and study normally.
Etiology
The causes of epilepsy are divided into three categories: (1) idiopathic: epilepsy in which no relevant structural changes or metabolic abnormalities have been found in the brain, but are more closely related to genetic factors; (2) symptomatic (secondary): epilepsy with clear brain lesions or metabolic disorders; and (3) cryptogenic: epilepsy that is suspected to be symptomatic but for which no cause has been found.
The International League Against Epilepsy classifies the etiology of epilepsy into six categories: genetic, structural, metabolic, and unknown etiologies, which have not yet been widely recognized [4].
Classification
(i) Classification of seizures
A classification scheme for seizures was developed by the International League Against Epilepsy (ILAE) in 1981, and the classification of seizures was revised by ILAE in 2001 and 2010. For example, in May 2001, the ILAE proposed that focal seizures were no longer classified as simple or complex, and autonomic seizures were not listed. New additions were also made to the seizure forms, such as negative myoclonus and inhibitory motor seizures [5]. The commonly used clinical seizures are summarized below.
Seizure classification
1. focal seizures
Simple focal seizures
Motor seizures
Sensory seizures
Autonomic seizures
Psychosomatic seizures
Complex focal seizures
Focal seizures secondary to generalized seizures
2. Generalized seizures
Tonic clonic seizures
Tonic seizure
Clonic seizures
Disoriented seizures (typical disoriented seizures, atypical disoriented seizures)
Myoclonic seizure
Loss-of-tension seizures
3. Seizures that cannot be classified
Epileptic spasms
(II) Classification of epileptic syndromes
Epileptic syndromes refer to a group of epilepsies with similar clinical manifestations and EEG changes. The diagnosis of epilepsy syndrome is often made clinically based on age of onset, symptomatology, etiology, family history, EEG and other information. In 1985, the ILAE classified epilepsy syndromes and revised them in 1989. Common epilepsy syndromes include infantile spasms, Dravet syndrome, benign childhood epilepsy with central-temporal spikes, childhood aphasic epilepsy, Panayiotopoulos syndrome, late-onset benign childhood occipital lobe epilepsy (Gastaut type), juvenile aphasic epilepsy, and juvenile myoclonic epilepsy.
Ancillary tests
1.Electroencephalogram: It is the most important adjunct to diagnose seizures and determine the type of seizures and epilepsy, and is a routine test for patients with epilepsy.
2. Neuroimaging: The purpose is to detect abnormalities in brain structures. MRI has high value in detecting structural abnormalities in the brain. If available, cranial MRI is recommended to be routinely performed. However, for small focal cortical dysplasia, it is often detected only after 1.5 years of age; therefore, if there is a high clinical suspicion of focal cortical dysplasia, cranial MRI needs to be repeated after 1.5 years of age. head CT examination is only able to detect gross structural abnormalities and has an advantage over MRI in showing calcified or hemorrhagic lesions.
3. Other ancillary tests: including blood biochemistry, cerebrospinal fluid, genetic metabolic disease screening, chromosome examination, genetic analysis, etc., are important in the search for the cause of epilepsy and are chosen to be performed according to the condition of the child.
Diagnosis
1. whether the seizure is unprovoked; 2. classification of seizure type based on clinical seizure and EEG performance on the basis of the diagnosis of seizure; 3. diagnosis of epilepsy syndrome based on the child’s age, symptomatology, EEG and other factors; 4. determination of the cause; 5. examination and overall assessment of the child’s individual development and related organ functions should be performed.
Treatment
(I) Treatment principles
To control seizures while minimizing adverse effects and improving the quality of life of the child. Therefore, the treatment of epilepsy should follow both the principles of treatment and take into account individualized differences. Treatment of epilepsy includes drug therapy, surgical treatment, and ketogenic diet therapy. When choosing a treatment plan, the characteristics of each child with epilepsy such as etiology, seizure type/syndrome classification, co-morbidities and family factors should be fully considered for individualized and comprehensive treatment.
(b) Etiological treatment: If the cause is clear, the etiological treatment should be actively performed.
(3) Anti-epileptic drug therapy
The basic principles of drug therapy include: (1) Anti-epileptic drugs should be selected according to seizure type, syndrome and family environment. If the syndrome cannot be diagnosed, drugs should be selected according to the type of seizure; (2) first monotherapy; (3) take drugs according to the pharmacokinetics of each drug; (4) monitor blood concentration regularly if necessary; (5) if drugs need to be replaced, there should be a gradual transition; (6) the course of treatment should be long, generally until at least 2 years of continuous seizure-free, and the EEG epileptiform discharges are completely or basically disappeared. (7) slow discontinuation of the drug, the process of discontinuation is generally required to be greater than 3-6 months; (8) throughout the treatment process should be regular follow-up, monitoring a variety of possible adverse reactions to drugs such as allergies, liver function damage, blood system involvement, etc. Currently, antiepileptic drugs are divided into, traditional antiepileptic drugs and new antiepileptic drugs. Traditional antiepileptic drugs mainly include phenobarbital (PB), valproic acid (VPA), carbamazepine (CBZ), phenytoin (PHT), clonazepam (CZP ), and new antiepileptic drugs mainly refer to those marketed after the 1990s and currently available in China, including lamotrigine (LTG), levetiracetam (LEV), oxcarbazepine (OXC), topiramate (TPM), zolpidem Zonisamide, etc.
Type of seizure
First-line drugs
Drugs that can be considered
Medications that may aggravate seizures
Generalized tonic clonic seizures
Valproic acid
Lamotrigine
Carbamazepine
Oxcarbazepine
Levetiracetam
Topiramate
Carbamazepine
Oxcarbazepine
Phenytoin sodium
Tonic or atonic seizures
Valproic acid
Lamotrigine
Topiramate
Carbamazepine
Oxcarbazepine
Disorientation episode
Valproic acid
Ethosuximide (no domestic drug)
Lamotrigine
Clonazepam
Levetiracetam
Topiramate
Zonisamide
Carbamazepine
Oxcarbazepine
Phenytoin sodium
Myoclonic seizures
Valproic acid
Levetiracetam
Topiramate
Clonazepam
Zonisamide
Carbamazepine
Oxcarbazepine
Phenytoin sodium
Focal seizures
Carbamazepine
Lamotrigine
Oxcarbazepine
Levetiracetam
Valproic acid
Phenytoin sodium
Phenobarbital
Zonisamide
(iv) Surgical treatment of epilepsy
If there is a clear epileptogenic focus (e.g., focal cortical dysplasia) and the effect of medical treatment is poor, preoperative evaluation for epilepsy surgery should be performed at a specialized epilepsy center. However, surgical treatment is, after all, invasive, and the risks and benefits of surgery should be evaluated at a specialized epilepsy center for epilepsy surgery.
Case.
Boy 7 years old, presented with “intermittent convulsions for 2 months”.
History: 2 months ago, the child had a convulsive seizure shortly after going to sleep, which was characterized by head tilting to the left, eyes squinting to the left, mouth tilting to the left, left hand clenching a fist, left upper limb shaking, and not responding to calls. The form and duration of the seizures were the same as before. His mental and motor development was normal before and after the onset of the disease. He ate and slept well, and his bowel movements were normal.
Past, personal and family histories: nothing special.
Physical examination: clear, responsive, Bp 100/70 mmHg, head circumference 52 cm, no milk coffee spots or pigment loss spots on the whole body. No abnormalities in heart, lung and abdominal examination. There was no abnormality in cranial nerve examination, normal muscle strength and tone of the limbs, symmetrical elicitation of tendon reflexes, pathological signs (-), meningeal stimulation signs (-). Auxiliary examinations: blood, urine and stool were not abnormal. Liver function, cardiac enzymes, renal function, electrolytes, pyruvate and beta hydroxybutyrate were normal. Head MRI: normal. EEG: (2011-7-14): bilateral spikes and slow waves in the Rolandic area, right-sided, with increased sleep periods.
Diagnosis: This child had 4 non-evoked seizures with seizure characteristics consistent with those of epileptic seizures (recurrent seizures, sudden onset and off, similar seizure form), EEG suggesting frequent epileptic discharges (suggesting the presence of a persistent tendency to produce seizures), and the diagnosis of epilepsy was established. The type of seizure was considered to be focal, based on the absence of complete loss of consciousness during the seizure, asymmetry of the seizure, and convulsions of one limb; the epilepsy syndrome was considered to be benign epilepsy in children with spikes in the central temporal region, based on the age of onset (7 years), the type of seizure, EEG features (Rolandic area discharges, significantly increased during sleep), and normal intellectual-motor development before onset. This epilepsy syndrome is generally considered to be caused by abnormal genetic factors. Treatment: The child is a school-age child with focal seizures and should be treated with drugs that have relatively little cognitive impact, such as oxcarbazepine and levetiracetam. During the medication period, attention should be paid to the side effects of the selected drugs such as allergy and liver function impairment, and the child should be followed up regularly at the outpatient clinic. At the same time, the child and parents should be informed of the following issues in treatment and life: (1) Adhere to long-term treatment and do not stop medication at will; (2) Maintain a healthy and regular life, especially avoiding sleep deprivation, overeating and overexertion, and try to remove or avoid triggers for seizures, if any. Whenever possible, children should be encouraged to participate in normal school life, but care should be taken to avoid accidental injuries, such as drowning and traffic accidents.
References.
1, Clinical Diagnostic and Treatment Guidelines Epilepsy Subvolume, edited by Chinese Medical Association, People’s Health Publishing House, July 2007, 4.
2, Fisher RS, van Emde Boas W, Blume W, et al. Epileptic seizures and epilepsy: definitions proposed by the International League Against Epilepsy (ILAE) and the International Bureau for Epilepsy (IBE). Epilepsia 2005;46:470C2.
3, Pediatrics, Wang Weiping, People’s Health Press, 8th edition, March 2013, 392-400.
4, Berg AT, Berkovic SF, Brodie MJ,et al. (2010) Revised terminology and concepts for organization of seizures and epilepsies: report of the ILAE Commission on Classification and Terminology, 2005C2009.Epilepsia 51:676C685.
5, Engel J, Jr. A proposed diagnostic scheme for people with epileptic seizures and with epilepsy: Report of the ILAE Task Force on Classification and Terminology. Epilepsia 2001;42:796-803.