Febrile Seizures

OCCASIONAL SEIZURESOCCASIONAL SEIZURES(ACUTE SYMPTOMATIC SEIZURES)(ACUTE SYMPTOMATIC SEIZURES)

PROF. DR. SANDA MAGUREANUDR. DIANA BÂRCĂ

PEDIATRIC NEUROLOGY DEPARTMENT, “AL. OBREGIA” CLINICAL HOSPITAL

“Humanity has but three

great enemies: fever, famine

and war; of these by far

the greatest, by far the

most terrible is fever.”

William Osler, 1897

OCCASIONAL OCCASIONAL (ACUTE SYMPTOMATIC) SEIZURESSEIZURES

DEFINITION

� Epileptic seizures occurring at any age – especially in infants and toddlers – as an answer of the CNS to an acute insult ( alteration of homeostatic constants – temperature, glycemia, acid-base equilibrium, phospho-calcemia, etc), in the absence of any epileptogenic lesion.

� frequently due to extracerebral changes, rather than to intracerebral ones

OCCASIONAL OCCASIONAL (ACUTE SYMPTOMATIC) SEIZURESSEIZURES

CLASSIFICATION

1. OCCASIONAL SEIZURES DUE TO EXTRACEREBRAL INSULTS :� Febrile seizures;� Hypocalcemic seizures;� Hypoglycemic seizures;� Acute dehydration -induced seizures;� Acute poisoning ( intoxication) – induced seizures;� Pyridoxine-deficiency induced seizures;

2. OCCASIONAL SEIZURES DUE TO INTRACEREBRAL INSULTS:

� Acute cerebral infections;� Seizures in brain tumors;� Seizures in brain trauma;� Seizures in stroke;

FFEBRILE SEIZURES (FS)EBRILE SEIZURES (FS)

� DEFINITION:

• “Sz occuring in childhood after 1 month of age, associated with 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” .

ILAEILAE

FFEBRILE SEIZURES (FS)EBRILE SEIZURES (FS)

� EPIDEMIOLOGY:

• strongly age-dependent - 3 mo – 5-6yrs:� 4% before 6 mo� 90% within first 3 yrs� 6% after age 3;

• produced in association with fever;• without any proved central nervous system infection

(encephalitis, meningitis);• the most frequent “convulsions” in infants• 2-7% children < 5 yrs: at least 1 FS;•• ♂ > ♀♂ > ♀;

FFEBRILE SEIZURESEBRILE SEIZURES

� ETIOPATHOGENESIS:

- insufficiently known;

- various factors with impact on cortical excitability:

1. Fever ;

2. Age ;

3. Inheritance ;


1. FEVER

etiology: upper respiratory airways infections, eruptive disease, urinary infections, gastroenteritis;

FS occur at sudden body core temperature rising;

75% at >39,5 C;


2. AGE:

- very important;

- rarely < 6 mo & > 4-5 yrs;

- Due to * brain maturation

* diminishing of infections incidence;


3. HEREDITARY FACTORS:

- AD transmission, with incomplete penetrance and age-related expression - incompletely clarified;

- + Family history for epilepsy: 10-50%;

- + Family history for FS: 33%;


� CLASSIFICATION:

� SIMPLE FEBRILE SEIZURES (SFS)(SFS)

� COMPLEX ( COMPLICATED) FEBRILE SEIZURES (CFS)(CFS)

SIMPLE SIMPLE FFEBRILE SEIZURESEBRILE SEIZURES

� 95% of total FS; 6 mo – 5 yrs;

�� uniqueunique episode in first 24 hours of a febrile episode ( body ext temp > 38°C );

� occur at sudden raise of the fever > 38°C;

!!!! fever must be present at least immediately after the fever must be present at least immediately after the szsz

( may not be detected before ( may not be detected before szsz));

�� shortshort < 15 min;

�� generalizedgeneralized ( tonic, hypotonic, tonic-clonic );

� in children without without neurologicneurologic deficitsdeficits ( no pre-, peri- or postnatal brain damage, normal psychomotor development, no afebrile seizure previously );

FFEBRILE COMPLEX SEIZURESEBRILE COMPLEX SEIZURES

� Rare - 4-5% of FS;

� Age at onset < 1yr;

� multiple;

� focal;

� prolonged > de 15 min;

� postictal abnormalities – frequent postictal palsy

DIAGNOSIS OF FS

� Rigorous history;

�� LUMBAR PUNCTURELUMBAR PUNCTURE:

� + meningeal signs

� patients < 6 mo (obligatory);

� patients under antibiotic therapy

� patients < 18 mo (recommended);

� strong suspicion of CNS infection

� in CFS.

meningitis may be masked

DIAGNOSIS OF FS

� EEG:- limited value

- in CFS: high dg value in viral encephalitis !

- epileptiform abn – may be expression of genetic predisposition (not future epilepsy indicator).

� Blood chemical tests (glycemia, calcemia) and other investigations – if the clinical picture is suggestive!!

� NEUROIMAGING: CT & MRI - not routinely.

DIFFERENTIAL DIAGNOSTIC :

� CNS infections – meningitis, encephalitis (40% cases do not have meningeal signs);

� anoxic seizures ( “cerebral“ syncope) – may be triggered by fever, fear, emotion, heart pathology;

� Shuddering, dystonic seizures

� Breath holding spells …

FEBRILE SEIZURESTREATMENT

1. ACUTE INTERVENTION;� SFS > 3 min� CFS

2. PREVENTION AND RECURRENCE RISK ;

1. ACUTE INTERVENTION

� Supportive measures: lateral decubitus position, removal of airway obstruction, venous access, O2.

� iv Diazepam: 0,5 mg/kg;

� antipyretics: acetaminophen, ibuprofen, lukewarm baths – DO NOT !!! use cold packs or ice. May cause shivering, increasing temperature

� etiological treatment – if the case;

� Calm the scared, anxious parents

CALM, DO NOT PANIC

2. PROPHYLACTIC TREATMENT:

a. Intermittent treatment – various regimes:

1. classical : at temp > 38ºC: antipyretics, Diazepam, 0,2-0,5 mg/kg/day per os during the febrile illness and 2 more days after fever resolution

2. if the FS recurs – the family will administrate Diazepam ir0,4-0,5mg/kgc , repeated 1 more time if there is still fever > 8 hours, max x3/24 hrs

b. Continuous treatment:

- does not prevent epilepsy

- ! side-effects of the AEDs (irritability, lethargy, cognitive impairment, liver/ pancreatic insufficiency ) –some may be permanent

- Phenobarbital 3-5mg/kg/day,

- Valproate 20-30 mg/kg/day;

2. PROPHYLACTIC TREATMENT:

� When? :

- children with high risk (≥ 3FS in 6 mo, ≥4 in 1yr),

- duration FS>15 min,

- FS requiring pharmacological intervention to be stopped

- frequent recurrences,

- abnormal psychomotor development

- frighten, anxious parents

2. PROPHYLACTIC TREATMENT

OUTCOME

� Mortality – very low

� PREDICTORS OF RECURRENCE (33-40%):

- familial history + for FS (Ist degree relatives) ;- short duration of fever prior to FS;- overall duration;- low temperature;- lateralized seizure;- age at onset : < 15 mo: 50-65%;

- 50-75% recurrences – in the Ist year;- infancy associates multiple recurrences (x3);

> 3 risk factors + : 50-100% cases - recurrence

OUTCOME

� Risks of neurological/ cognitive impairment :

- low in previously normal, healthy chidren;- after some CFS: hemiplegia, diplegia, coreoatetosis- frequent:

- minor neurologic signs,

- behaviour disorders (hyperkinetic sdr);- learning disabilities;

OUTCOME

� PREDICTORS FOR EPILEPSY :

� FS > 15 min;

� More FS in 24 ore;

� Familial history + for epilepsy

� Neurologic abnormalities;

FS & EPILEPSY

� Approximate history of FS in specific epileptic sindromes:� BRE - 8%

� BOE – 15%

� CAE – 15%

� JME – 8%

� Myoclonic-astatic epilepsy – 28%

� Febrile seizures plus – 90%

Current Opinion in Neurology, 1998

� From pathogenic point of view, FS are considered a sudden reaction to a high fever, in a child with genetic predisposition, at the age of low convulsive threshold of the immature brain. (Moshe,

1989)

Documents

Febrile Seizures