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Febrile convulsions in children
Last reviewed: 23.04.2024
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Febrile convulsions develop in children younger than 6 years with an increase in body temperature above 38 ° C, the absence of a history of afebrile seizures and other possible causes. The diagnosis is clinical, it is put after excluding other possible causes. Treatment of an attack of seizures lasting less than 15 minutes is supportive. If convulsions last for 15 minutes or more, the treatment includes lorazepam intravenously and in the absence of the effect of phosphenytoin intravenously. As a rule, prolonged maintenance medication of febrile seizures is not shown.
[What causes febrile convulsions in children?
Febrile convulsions occur in about 2-5% of children under 6 years of age; in most cases, the age of children from 6 to 18 months. Simple febrile convulsions last less than 15 minutes and occur without focal symptoms, and if they occur in series, the total duration is less than 30 minutes. Complex febrile seizures last more than 15 minutes, with focal symptoms or post-paresis paresis, or convulsive seizures occur in series with a total duration of more than 30 minutes. Most (more than 90%) of febrile seizures are simple.
Febrile convulsions occur against bacterial or viral infections. They also sometimes develop after some vaccinations, such as DTP (whooping cough and diphtheria and tetanus toxoid) or trivaccine (measles, rubella, mumps). Genetic and family factors can increase susceptibility to febrile seizures. Monozygotic twins have significantly higher concordance than dysygotic twins.
Symptoms of Febrile Seizures in Children
Often, febrile convulsions occur during the initial rise in temperature, and most of them develop in the first 24 hours of fever. Characterized by generalized convulsions; in most cases, convulsions are clonic, but some manifest themselves as periods of atonic or tonic posture.
Seizures are diagnosed as febrile after exclusion of other causes. Fever can also cause seizures in children with episodes of afebrile seizures in the anamnesis; in such cases it is not febrile convulsions, since the child already had a predisposition to convulsions. If a child is less than 6 months old, he has meningeal signs or signs of CNS depression or convulsions developed after several days of febrile fever, you should take a spinal fluid to study to exclude meningitis and encephalitis. Sometimes it is necessary to conduct a laboratory examination for metabolic disorders or metabolic diseases. You should determine the level of glucose, sodium, calcium, magnesium, phosphorus, as well as liver and kidney function, if a child has recently had diarrhea, vomiting, or low fluid intake; if there are signs of dehydration or swelling or in case of complicated febrile seizures. CT or MRI of the brain should be prescribed in the presence of focal neurological symptoms or signs of increased intracranial pressure. EEG usually does not allow to identify a specific cause or predict a relapse of seizures; it is not recommended after the first attack of febrile seizures in children with normal results of a neurological examination. One should think about the appointment of EEG after complicated or recurrent febrile seizures.
Treatment of febrile seizures in children
The treatment is maintained for a duration of an attack less than 15 minutes. Convulsions lasting more than 15 minutes require the use of medications to stop them, with careful monitoring of the condition of hemodynamics and respiration. It may be necessary to intubate the trachea if the response to the drugs is not fast and the seizures continue.
Preparations are usually administered intravenously, using short-acting benzodiazepines (eg, lorazepam at 0.05-0.1 mg / kg, which can be re-injected after 5 minutes, up to 3 injections). Phosphenytoin 15-20 mg PE (phenytoin equivalent) / kg may be given after 15 minutes if seizures continue. Rectal gel of diazepam 0.5 mg / kg can be administered once, and then repeated after 20 minutes if lorazepam can not be administered intravenously.
Supportive drug treatment to prevent recurrent episodes of febrile seizures or the development of afebrile seizures is usually not indicated unless the child has had multiple or prolonged episodes of seizures.
What is the prognosis of febrile seizures in children?
Repeated febrile seizures in children account for about 35%. The probability of a relapse is higher if the child is younger than 1 year with the first episode of seizures or the child has relatives of the first line of relationship who have had febrile convulsions. The probability of developing a febrile seizure syndrome after febrile seizures is approximately 2-5%.