بسم هللا الرحمن الرحیم

Pediatric Febrile Seizures

Dr. Mujeebullah Mahboob

Resident doctor at FMIC

07/01/2016

Objects of presentation

• Introduction and History of febrile convulsion • Pathophysiology of • Epidemiology of • Etiology of • Evaluation of • Treatment of • Prevention of • Conclusion

Historical background

• Although Febrile seizure was described by the ancient Greeks but until this century it was not recognized that febrile seizures are distinct syndrome separate from epilepsy.

• In 1980, a consensus conference held by the National Institutes of Health(US) described febrile seizure.

Introduction

• Febrile seizures are seizures that occur between the age of 6 and 60 mo(3mo-5y).

• with a temperature of 38°C (100.4°F) or higher, that are not the result of central nervous system infection or any metabolic imbalance, and

• that occur in the absence of a history of prior afebrile seizures.

Introduction

• Another definition from the International League Against Epilepsy (ILAE) is:

• "a seizure occurring in childhood after 1 month of age associated with a febrile illness not caused by an infection of the CNS, without previous neonatal seizures or a previous unprovoked seizure, and not meeting the criteria for other acute symptomatic seizures."

Classification

SFC

generalized

not recurrent within a

24-hr period

lasting for a maximum of

15 min

associated with fever

tonic–clonic

Complex febrile seizure

More

prolonged (>15 min)

Focal

Reoccurs within 24

hr

• is a febrile seizure lasting longer than 30 min

Febrile status epilepticus

• recurrent febrile seizures within 24 hr

simple febrile seizure plus

• Age and fever are the same as for simple febrile seizure

• The child has a preexisting neurologic abnormality or acute illness

Symptomatic febrile seizure

Postictal state

• Most patients with simple febrile seizures

• have a very short postictal state and usually return to their baseline normal behavior and consciousness within minutes of the seizure.

• postictal period of sleepiness, headache or confusion can extend beyond the 15-minute maximum.

• A weak limb postictally will role out SFC.

Exclusion to the diagnosis

• Hx of previous afebrile seizure

• CNS infection or inflammation

• Acute systemic metabolic abnormality causing seizure.

Pathophysiology

• Febrile seizures occur in young children at the time of their development when the seizure threshold is low.

• Younger children are susceptible to frequent infections such as upper respiratory infection, otitis media, viral syndromes, and they respond with comparably higher temperatures.

Pathophysiology

• Animal studies suggest a possible role of endogenous pyrogens, such as interleukin 1beta, that, by increasing neuronal excitability, may link fever and seizure activity.

• Hypothesis is present that during febrile illness the cytokine network is activated and may have a role in the pathogenesis of febrile seizure.

Etiology

• As Febrile seizures tend to occur in families this strongly suggests genetic predisposition.

• In most cases the disorder appears to be polygenic.

• A small number of families are identified with an autosomal dominant pattern of inheritance of febrile seizures.

Etiology

• Underlying mutations have been found in genes encoding the sodium channel and the gamma amino-butyric acid A receptor.

• If there is one child with febrile seizure in the family the risk of febrile seizure in other siblings is 10%

• and 50% for the siblings if a parent has febrile seizure.

Etiology

• ARI are most commonly associated with febrile seizures (otitis media or pharyngitis), pneumonia.

• AGE, especially caused by Shigella or campylobacter and UTI are less common causes.

• Viral rather than bacterial infection causes disturbance of cerebral electrical activity.

• Roseola infantum is rare but classic cause.

• One study implicated viral causes 86% in of cases.

• After vaccination of DPT or MMR (Starting MMR/MMRV vaccination earlier may reduce seizure risk)

Etiology • Viral causes:

– Roseola and

– Human herpesvirus (HHV-6B) and HHV-7 infection

• No data support the theory that a rapid rise in temperature is a cause of febrile seizures.

• Simple febrile seizures often occur with the initial temperature elevation at the onset of illness. The seizure may be the first indication that the child is ill. While no clear cutoff is known, a rectal temperature under 38°C should raise concern that the event was not a simple febrile seizure.

Seizures are not related to the degree of temperature

Epilepsy syndromes typically start with febrile seizures

• generalized epilepsy with febrile seizures plus (GEFS+)

• severe myo-clonic epilepsy of infancy (also called Dravet syndrome)

• temporal lobe epilepsy secondary to mesial temporal sclerosis due to prolonged febrile seizure.

generalized epilepsy with febrile seizures plus

• GEFS+ is an autosomal dominant syndrome.

• Clinical feature is highly variable.

• Onset is usually in early childhood and remission is usually in mid-childhood.

• It is characterized by multiple febrile seizures and by several subsequent types of afebrile generalized seizures, including generalized tonic–clonic, absence, myoclonic, atonic, or myoclonic astatic seizures with variable degrees of severity.

Dravet syndrome

• Dravet syndrome is the most severe form of febrile seizure-associated epilepsies.

• Onset is in infancy as febrile and afebrile unilateral clonic seizures.

• Seizures recurring every 1-2months.

• seizures are typically induced by fever, but they differ from the usual febrile convulsions in that they are more prolonged, are more frequent, are focal and come in clusters.

Dravet syndrome

• Seizures typically occurs with low grade fever and then without fever.

• developmental delay usually follows.

• Patients who have got Vaccine encephalopathy(seizures and psychomotor regression occurring after vaccination ) are now turn out to have Dravet syndrome mutations, indicating that their disease is caused by the mutation and not secondary to the vaccine.

Epidemiology

• Febrile seizure is the most common cause of childhood convulsion disorder.

• Between 2% and 5% of neurologically healthy infants and children experience at least 1, usually simple, febrile seizure.

• Febrile seizures are twice as common in boys than girls.

Mortality

• SFC do not have an increased risk of mortality

• Seizures that are Complex 0ccured before age 1year or were triggered by Tem of <39c were associated with a 2-fold long-term increase in mortality probably secondary to coexisting pathology

• There are no long-term adverse effects of having 1 or more simple febrile seizures

Morbidity

• Age-matched controls studies showed that patients with febrile seizures do not have any increase in the incidence of abnormalities of behavior, scholastic performance, neurocognitive function, or attention.

Recurrence

• Febrile seizures recur in approximately 30% of those experiencing a first episode, in 50% after 2 or more episodes, and in 50% of infants younger than 1 yr old at febrile seizure onset.

Risk of epilepsy

• only 2-7% of children who experience febrile seizures proceed to develop epilepsy later in life

EVALUATION OF A PATIENT WITH FEBRILE SEIZYRE

History

• The type of seizure (generalized or focal) and its duration should be described to help differentiate between simple and complex febrile seizures.

• Focus on the history of fever, duration of fever, and potential exposures to illness.

• A history of the cause of fever (e.g., viral illnesses, gastroenteritis) should be elucidated.

History

• Recent antibiotic use is particularly important because partially treated meningitis must be considered.

• A history of seizures, neurologic problems, developmental delay, or other potential causes of seizure (e.g., trauma, ingestion) should be sought.

Physical Examination

• The underlying cause for the fever should be sought.

• A careful physical examination often reveals otitis media, pharyngitis, or a viral exanthema.

• Serial evaluations of the patient's neurologic status are essential.

• Check for meningeal signs as well as for signs of trauma or toxic ingestion.

DDx

• Meningitis and Encephalitis are important causes of seizure and fever in pediatrics.

• To differentiate a febrile seizure from these two types of CNS infection the only way is CSF analysis when clinical suspicion is present.

WORKUP FOR FEBRILE SEIZURE

Work Up • Blood Studies

• C.S.F analysis (Lumbar Puncture)

• Electroencephalogram (EEG)

• Neuroimaging (CT&MRI)

Blood Studies

• Serum electrolytes, calcium, phosphorus,

magnesium, and CBC) are not routinely recommended in the work-up of a child with a first simple febrile seizure.

• Blood glucose should be determined in children with prolonged postictal state or in case of poor oral intake (prolonged fasting).

Blood Studies

• Any need for doing blood studies in a patient

with a SFC should be suggested by the History or physical examination.

• A low sodium level is associated with higher risk of recurrence of the febrile seizure within the following 24 hr.

Indications of CSF analysis

• All infants younger than 6 mo.(some references mentioned less than 12mo) of age who present with fever and seizure(because the signs and symptoms of bacterial meningitis may be minimal or absent in this age group.).

• If the child is ill-appearing.

• At any age if there are clinical signs or symptoms of concern.

Indications of CSF analysis

• A lumbar puncture is an option in a child 6-12 mo of age who is deficient in Haemophilus influenza type b and Streptococcus pneumonia immunizations or for whom immunization status is unknown.

• A lumbar puncture is an option in children who have been pretreated with antibiotics (it can mask signs and symptoms of meningitis ).

• Generally a minimal suspicion for meningitis.

Indications of CSF analysis

• Children less than 18mo old in whom the cause of fever is unknown.

• Presence of fever for more than 48-72hrs before occurring of seizure.

• In children older than 6years febrile convulsions are rare and we must investigate for CNS infections, electrolyte imbalance or other CNS cause.

Risk factors for meningitis

• A visit to a healthcare setting within the previous 48 hours

• Seizure activity at the time of arrival in the ED

• Focal seizure, suspicious physical examination findings (e.g., rash, petechiae) cyanosis, hypotension, or grunting

• Abnormal neurologic examination

• Pretreatment with antibiotics, as it can mask signs and symptoms of meningitis

Electroencephalogram (EEG)

• An electroencephalogram (EEG) is not

necessary in the routine evaluation of a child with a first simple febrile seizure and is otherwise neurologically healthy.

• Generally EEG is restricted to special cases in which epilepsy is highly suspected, and, generally, it should be used to specify the type of epilepsy rather than to predict its occurrence.

Electroencephalogram (EEG)

• Another indication for EEG is when the

patient does not recover immediately from a seizure, then an EEG can help distinguish between ongoing seizure activity and a prolonged postictal period, sometimes termed a nonepileptic twi-light state

Electroencephalogram (EEG)

• children with febrile status epilepticus (severe

type of complex febrile seizure) within 72 hours of presentation had an abnormal EEG with focal slowing seen maximally over the temporal areas and were highly associated with MRI evidence of acute hippocampal injury

Electroencephalogram (EEG)

• An EEG would not predict the future

recurrence of febrile seizures or epilepsy even if the result is abnormal.

• EEGs performed within 2 wk of a febrile seizure often have nonspecific slowing, usually posteriorly. Thus, in many cases, if an EEG is indicated, it is delayed until or repeated after more than 2 wk have passed.

Neuroimaging

• A CT or MRI is not recommended in evaluating the child after a first simple febrile seizure.

• The work-up of children with complex febrile seizures needs to be individualized. This can include an EEG and Neuroimaging, particularly if the child is neurologically abnormal.

Neuroimaging

• 11% of children with febrile status epilepticus are reported to have (usually) unilateral swelling of their hippocampus acutely, which is followed by subsequent long-term hippocampal atrophy. These patient may or may not developed Temporal lobe epilepsy.

• MRI will help to detect this swelling of the hippocampus acutely.

TREATMENT

• Prehospital Care

• Emergency Department Care

• Inpatient Care

• Patient Education

Prehospital Care

• Patients with active seizures should be treated

with airway management, high-flow oxygen, supportive care, and anticonvulsants as necessary. Acute treatment such as rectal diazepam (0.5 mg/kg) and buccal 0.4-0.5 mg/kg) or intranasal (0.2 mg/kg) are effective and can be given at home for a seizure lasting longer than 5 minutes.

• Patients who are postictal should receive supportive care and antipyretics as appropriate.

Emergency Department Care

• Patients presenting with status epilepticus

should be treated with airway management and anticonvulsants as necessary(ABC).

• Patients presenting with history and physical examination findings consistent with a simple febrile seizure should have frequent neurologic examinations to monitor mental status.

• Other causes of seizure should be ruled out.

Emergency Department Care

• The cause of the febrile illness should be

sought and treated.

• Antipyretics should be considered. Acetaminophen and ibuprofen are often used.

• Parental anxiety and fear that their child may die or will develop brain damage needs to be addressed with reassurance and education.

Inpatient Care

• The decision to admit should be

individualized, but admission usually is not necessary for patients with febrile seizure.

• Most patients should be observed in the ED until awake and alert.

Inpatient Care

• Conditions requiring admission of the patient

include the following:

More than 1 seizure within 24 hours

Unstable clinical status

Lethargy beyond the postictal period (slow recovery)

If close follow up is not possible.

Medication

• Antipyretics

• Anticonvulsant agents

Antipyretics

• Antipyretics can decrease the discomfort of

the child but do not reduce the risk of having a recurrent febrile seizure, probably because the seizure often occurs as the temperature is rising or falling.

Anticonvulsant agents

• In general, antiepileptic therapy, continuous or intermittent, is not recommended for children with 1 or more simple febrile seizures.

• If the seizure lasts for longer than 5 min, acute treatment with diazepam, lorazepam, or mid-azolam is needed, best route of administration is Rectal or buccal and nasal.

• IV benzodiazepines, phenobarbital, phenytoin, or valproate may be needed in the case of febrile status epilepticus.

Patient Education

• Parents should be counseled about the

relative risks of recurrence of febrile seizures and recurrence of epilepsy, educated on how to handle a seizure acutely, and given emotional support.

• Parents should be counseled on the benign nature of febrile seizures.

• Parents should be reassured that simple febrile seizures do not lead to neurologic problems or developmental delay.

Febrile seizure prophylaxis

• Continuous or intermittent prophylaxis of febrile seizure with anticonvulsants is indicated when:

If 3 or more febrile seizures in 6months occurred.

6 or more in 1year.

Febrile seizure lasting more than 15minutes or requiring pharmacologic therapy to control seizures.

If medical reassurance fails to relieve the anxiety of parents.

Febrile seizure prophylaxis

• Intermittent prophylaxis with drugs that attains drug levels quickly can reduce, but do not eliminate, the risks of recurrence of febrile seizures can be given during febrile illnesses:

– intermittent oral diazepam (0.33 mg/kg every 8 hr during fever)

– intermittent rectal diazepam (0.5 mg/kg as a rectal suppository every 8 hr)

– nitrazepam, clobazam, and clonazepam (0.1 mg/kg/day) clobazam(0.75-1mg/kg) have also been used.

Febrile seizure prophylaxis

• Continuous prophylaxis is indicated: Failure of intermittent Rx Recurrent atypical seizures When parents are not able to promptly recognize the

onset of fever.

• Continuous phenobarbital (4-5 mg/kg/day in 1 or 2 divided doses),

• Continuous valproate (20-30 mg/kg/day in 2 or 3 divided doses).

• Phenytoin and carbamazepine are ineffective for prophylaxis.

Febrile seizure prophylaxis

• Iron deficiency(IDA) is associated with an increased risk of febrile seizures, and thus screening for that problem and treating it appears appropriate.

• A study found the European children with febrile seizures have lower Ferritin than those with fever alone, and iron deficiency, but not anemia, is associated with recurrence.

Conclusion

• Simple febrile seizures may slightly increase the risk of developing epilepsy, but they have no adverse effects on behavior, scholastic performance, or neurocognition. The risk of developing epilepsy is increased further in children with a history of complex febrile seizures.

• A strong association exists between febrile status epilepticus or febrile seizures characterized by focal symptoms and later development of temporal lobe epilepsy. Children with febrile seizures have a slightly higher incidence of epilepsy compared with the general population (2% vs. 1%).

References

• Nelson TEXTBOOK of PEDIATRICS EDITION 20

• Current pediatrics diagnosis and treatment 17th edition

• Ghai OP,gupta piyush ,Paul ,VK2004.Essentials Pediatrics Edition 8th edition

• Akbar khan ,parvez ,kundizafarullah ,2002 Basis of pediatrics 8th Edition

• http://www.medscape.com

• https://www.google.com

Prepared By

• Dr. Mujeebullah mahboob

• 1st year resident of Ped-Med at FMIC, Kabul, Afghanistan

• 10/01/2016

• W_mahboob@yahoo.com

• (+)93 798984142