Convulsions, epileptic seizures are a common ailment in children. The first 28 days of life, called the neonatal period, is the period with the most epilepsy among all age groups. In fact, the younger our brain is, the more prone it is to have seizures.
We encounter two types of remittances. Convulsions with fever and without fever. If the child has a fever above 38 degrees during or just after the epileptic seizure, we consider this as a febrile seizure. In general, febrile seizures tend to be more benign. Most do not continue beyond 6 years of age. However, convulsions without fever can occur until older ages.
A few parameters should be evaluated in order to evaluate whether the feverless convulsions are benign or malignant. We think that the shorter and less frequent the relapse is, the more benign it will be. Frequent seizures, in which the whole body is affected and the child becomes sluggish after seizures, have a greater risk of affecting intelligence development. Some types of seizures, such as the convulsions seen in West Syndrome, can be a harbinger of a bad course. In general, only seizures during sleep can be considered more benign.
If we can control the epilepsy attacks with a drug, we think that we are dealing with a mild epilepsy. In these cases, 2 years of seizure-free time is a safe approach to discontinue medications. It would be more accurate to consider this period as an average, because drug use can be as short as 1 month, or it can continue for years.
Sometimes seizures can be more difficult to stop. We may have patients who use two or three drugs at the same time. If seizures cannot be controlled with the first two drug trials, this is called resistant epilepsy.
The definition of epileptic syndrome can be made as “a specific epileptic condition with its signs and symptoms”. Epileptic syndromes in children are defined by considering the age of onset, seizure type, electroencephalography (EEG) findings, and accompanying clinical features (1). Recognition of epileptic syndromes allows treatment choice and prediction of the course of patients with appropriate diagnostic examination. In this review, the diagnosis, treatment and course of epileptic syndromes seen in newborn and infancy will be discussed. Neonatal epileptic syndromes Epileptic syndromes in the neonatal period, where epileptic events are common, are very rare. Four epileptic syndromes in newborns were described in the 1989 classification of the International Society for Combating Epilepsy (ILAE) and in the 2006 report of the epileptic syndromes working group (2,3).
Benign idiopathic neonatal seizures
Seizures, also called “fifth day seizures”, are seen between the 4th and 6th days of healthy newborns without a family history of seizures. This condition, which constitutes approximately 7% of all neonatal seizures, is seen twice as frequently in boys than in girls (4,5). Clonic status epilepticus, which may be accompanied by apnea, is the most prominent seizure type. Seizures are frequent recurrent unilateral clonic seizures or after lasting two hours to a day without interruption and do not recur. Zinc deficiency, viral infections and nutritional preferences are suspected in the etiology (6). Seizure is detected as more prominent rhythmic spike-slow waves in the centrotemporal region on EEG. The presence of 4-7 Hz side-changing theta wave activity in the EEG between seizures is determinative for the disease (7,8). Prolonged seizures can be stopped with benzodiazepines and phenytoin. Since the seizures regress spontaneously, they do not require maintenance therapy. The course of the disease is very good. Despite the status epilepticus picture, neuro-cognitive effects or recurrent seizures are not observed in patients (4,5).
Selim familial neonatal seizures
Benign familial neonatal seizures is a rare autosomal dominant (dominant) channelopathy. Seizures occur in the first week of life, often on the second or third day. Seizures that begin with tonic stance or apnea continue with gliding of the eyes, motor automatisms and clonia. Clonic contractions are often unilateral (9). Mutations in the genes of voltage-dependent potassium channels KCQ2 and KCQ3 are responsible for the etiology. These channels regulate the M-current, which determines the resting membrane potential (10,11). Asymmetric spike-wave complexes are seen in the seizure EEG. Physical examination and EEG findings of newborns are normal in the period between seizures (8). Most of the patients have a history of uneventful pregnancy and delivery. Seizures disappear by the end of the first week. At follow-up, approximately 16% of patients Seizures with or without afebrile have been reported. Neuro-cognitive development is not affected in patients (9,10).
Ohtahara syndrome, one of the severe epileptic encephalopathy pictures in newborns, was first described in 1976. The disease begins with successive tonic contractions in the first three months. Tonic contractions are flexor or extensor movements lasting 1-10 seconds, and the number of seizures per day can exceed 100. Focal clonic seizures are also seen in one third of the cases. 2-6 seconds in electroencephalography. 3-5 seconds following intense high-voltage multifocal spike-waves. lasting voltage suppression (Börst-Suppression) is detected (12,13). Structural brain anomalies are often responsible for the etiology. Hemimegancephaly, porencephaly, Aicardi syndrome, Oliver Dentat dysplasia, mamilar body agenesis, cerebral dysgenesis and cortical dysplasias have been associated with the disease. It is thought that cryptogenic forms result from micro dysgenesis or neuronal migration anomalies that cannot be detected by imaging methods (14). Seizures in Ohtahara syndrome are resistant to treatment. Response to valproic acid, benzodiazepines, ACTH, corticosteroids and high-dose pyridoxal phosphate used in treatment is limited. The effect of the ketogenic diet is controversial (15). Epilepsy surgery can reduce the number of seizures and support psychomotor development, especially in patients with cortical dysplasia (16). With age, seizures become typical infantile spasms; EEG findings turn into hypsarrhythmia. Although seizure control can be achieved in half of the patients who can reach school age, psychomotor retardation is observed in most of them (17).
Early myoclonic encephalopathy
Early myoclonic encephalopathy (EMA) is an epileptic condition with a poor prognosis in which voltage suppression is seen in the EEG that begins in the first three months of life. It shows similarities with Ohtahara syndrome in terms of early onset age, encephalopathic course, resistance to treatment, and EEG findings (18). Myoclonies are most commonly seen on the distal ends of the extremities, face and eyelids. Partial seizures are as common as myoclonias. These seizures are in the form of eye roll, apnea and asymmetric tonic posture. Another seizure type seen in the disease is tonic spasms (19). In most of the cases, the underlying cause cannot be revealed. Contrary to Ohtahara syndrome, in which structural disorders are at the forefront, metabolic or genetic diseases have been associated with EMA. Non-ketotic hyperglycinemia, propionic aciduria, methylmalonic acidemia, D-glyceric acidemia, sulfite or xanthine oxidase deficiency, Menkes disease and Zellweger syndrome are the main metabolic disorders known to cause this disease. Multifocal spike waves accompanying the slow background activity in the wakefulness EEG are replaced by the appearance of voltage suppression during sleep (17-20). Standard drugs and corticosteroids have limited effect on seizures. Although myoclonies decrease with age, partial seizures gain resistance. Most of the patients die at an early age. Resistant seizures and severe psychomotor retardation are observed in survivors (21).
Infant epileptic syndromes
Epileptic syndromes seen in infancy often lead to seizures and cognitive impairment that continue in later ages. West syndrome, Dravet syndrome and Doose syndrome, which are epileptic syndromes of this period, are also classified as epileptic encephalopathies.
The most well-known epileptic syndrome of infancy is undoubtedly West syndrome (WS). The frequency of the disease is 25 per 100 000 live births, and it occurs most frequently between the 4th and 7th months of life (22). This situation was first described by West in 1841; Typical seizures called infantile spasm are evident with hyparrhythmia on EEG and psychomotor retardation (23). Typical spasms are flexor/extensor contractions on both sides of the body, usually lasting 2-5 seconds, keeping all muscle groups symmetrical. Spasms are usually seen in series with intervals of 5-30 seconds. Most are sleep-related and occur at or immediately after waking (24). In the studies performed with video-EEG, many atypical spasms called “subtle spasm”, which are detected in cases with symptomatic etiology and progress with very small contractions in isolated muscle groups (such as face, eye, neck, shoulder), have been described apart from typical spasms. Such atypical spasms are very difficult to recognize and can easily be overlooked. WS should be considered in every infant with the same type of repetitive movements or developmental arrest (25). Hypsarrhythmia on wakefulness EEG; multifocal spikes intermingled with diffuse irregular high-voltage slow waves, marked by multiple spikes, sharp waves, while dormant hypsarrhythmia; it appears as periodic, diffuse irregular slow wave, spike wave paroxysms (23,24). “Visual agnosia” and cognitive impairment are most prominent in psychomotor regression. Cognitive impairment is associated with both epileptic seizures and hypsarrhythmia (26,27). According to the etiology, WS is symptomatic, cryptogenic and idiy.