Afebrile seizure in a child

 

Any child presenting with ‘non-febrile’ seizure requires a thorough history, along with a focussed examination to arrive at a working diagnosis.

 

Seizures may be epileptic (originating due to an electric disturbance in the brain) or non-epileptic (secondary effect of hypoglycaemia, electrolyte imbalance, etc) in origin.

 

 

HISTORY

Context including: What was the child doing, where were they, who witnessed, what drew their attention, any trigger, any pre-seizure symptoms?

 

Nature of actual seizure, including duration of each stage

– Onset of seizure- any focal features like turning eyes or head to a side, twitching on one side?

– Aura– older children can be asked about any aura, which may suggest focal onset

– Eyes open/ shut/ staring (ahead or to a side), eyes jerking, eyelid flutter

– Motor component- any stiffening/ jerking (fast/ slow), twitching of face/ eyelids

– Responsiveness during seizure, any vocalisations?

– Breathing abnormal? Cyanosis/ pallor

– Post seizure details including drowsiness or confusion (duration), Incontinence, Tongue bite

 

Enquire about other important features including:

– Any precipitating factor– recent illness, head injury, sleep deprivation, fluid balance problems?

– Headache, Vomiting, Weakness, Confusion?

– Early development and current developmental milestones

– Learning, behaviour, concentration problems, schooling problems etc.

– Family history of epilepsies, arrhythmias, sudden death, faints, etc.

 

EXAMINATION to include

– Conscious level and review of GCS monitoring

– Head circumference in young children under 3y age

– Signs of dysmorphism or neurocutaneous syndromes

– Any signs of trauma

– Cardiovascular examination including BP

– Neurological assessment at presentation and after recovery, including Cranial nerves and fundoscopy (if possible), Cerebellar signs, Gait and Abnormal posturing/ signs of raised ICP.

 

Admit or observe if:

– Unwell children, suspected meningitis / raised ICP

– Children < 18 months

– Worrying seizures- prolonged / multiple / focal seizures

– GCS < 15 even after 1 hour post seizure

– Children with new neurological signs

– High parental anxiety

 

If the patient is known to have epilepsy, consider

• Any likely explanations? (inter-current illness, non compliance- manage accordingly)
• Has the child gained weight to outgrow the dosage?
• If no cause found, consider checking levels especially if on Carbamazepine or Phenytoin
• Once fully recovered, discharge home with advise; ensure safely advise &follow up;

 

Investigations

Not all children with a first afebrile seizure need investigation.

Perform ECG in all motor seizures; and Blood Glucose if a child is still seizing or not fully alert.

 

ECG- in all children with convulsive (motor) seizures to check for rhythm abnormalities, evidence of pre-excitation (delta waves) and calculating QTc

 

FBC, U&E, Blood Glucose, Bone Profile, Mg, CRP and urine analysisin children with intercurrent illness, or if young child <18 months age, or if they had prolonged or multiple seizures.

Include any other investigations guided by the clinical suspicion.

 

Lumbar Puncture: Children with any of these features have an increased risk of meningitis and a lumbar puncture should be consideredif there are no contraindications.Consider LP in children <18 months as they may not display signs of meningitis.

 

Contraindications to LP

• Drowsiness or impairment of consciousness (falling conscious level, Glasgow coma scale <13)
• Signs of septicaemic shock (poor perfusion, low BP, and tachycardia)
• Clinical diagnosis of invasive meningococcal infection with typical haemorrhagic rash
• Signs of raised intracranial pressure (papilloedema, coma, high BP, low pulse)
• Focal neurological signs

 

EEG is not routinely needed after a simple first afebrile seizure. An EEG will help differentiate between focal and generalised seizures, guide the need for further investigation, and influence decisions to commence anticonvulsant treatment. 

It may be requested after a focal / prolonged / recurrent / atypical (e.g. Infantile spasms) seizure

Remember- interictal EEGs can be normal and does not exclude diagnosis of an epilepsy.

 

Neuroimaging- CT Brain may be used to investigate an acute neurological disorder e.g. traumatic brain injury, encephalitis, intracranial abscess, raised ICP, or brain tumour.

 

MRI is not required in all children, butshould be considered in

– Children under 2y age with recurrent seizures 

– Focal onset features on history, examination or EEG 

– Poor control of epilepsy despite first-line medication

– Neurodevelopmental disorders like Cerebral palsy, Learning disability, Autism or neurocutaneous syndromes

 

Discharging home:

At the end of assessment, consider the working diagnosis as:

1. Epileptic episodeINV not always needed; Treatment generally not offered after a single seizure. Ensure discussion about risk; safety; first-aid; need to keep a diary if further events & follow up in epilepsy clinic
2. Acute symptomatic seizure-Investigate for possible underlying cause & treat accordingly
3. Non-epileptic event-What is the likely diagnosis? Further advise accordingly
4. Not yet certain-Consider the risk factors, parental anxiety & worrying features; Give safety advice, ask to keep a symptom diary & offer follow up

 

If child has completely recovered with a normal BP and ECG, they may be discharged home after parental counselling. Inform if any investigations and follow up in epilepsy clinic will be arranged.

 

If the presentation included prolonged or recurrent seizures and child is at risk for such events, the emergency advice should be to call an ambulance at 5 minutes; or consider providing rescue medication like buccal Midazolam.

 

Prognosis

Some children after the first epileptic seizure will go on to have further epileptic seizures and be diagnosed with epilepsy.

Around 10% of the population will have a seizure at some point in their lives.

A first seizure provoked by an acute brain disturbance (symptomatic) will recur in only 3-10% cases.

Around 1% of children will have an afebrile seizure by the age of 16, of which 30-50% will recur over the next two years.

After a second unprovoked epileptic seizure 70-80% will recur.