Afebrile seizure in a child
We’ve all encountered seizures that are provoked by fever, and we have a clear pathway for managing them.
But what about when a child has a seizure without a fever? The absence of a clear trigger can make these events feel more mysterious and raise a host of questions.
Afebrile seizures in children are seizures that occur without a fever. They are a common neurological event that can cause significant anxiety for parents and require careful evaluation by healthcare professionals.
Types of Afebrile Seizures
Provoked seizures: These are caused by an identifiable, non-fever-related trigger, such as a head injury, electrolyte imbalance, or a central nervous system infection.
Unprovoked seizures: These occur without a clear, immediate cause. A single unprovoked seizure may be a one-off event, but if a child experiences two or more unprovoked seizures, they are diagnosed with epilepsy.
A comprehensive and systematic approach is crucial to determine the cause and guide proper management.
History
A detailed history is the single most important part of the evaluation. It provides vital clues about the nature of the event and potential triggers.
Event Context:
What was the child doing when the seizure began?
Who witnessed the event and what specifically drew their attention?
Was there any potential trigger, such as sleep deprivation or a recent head injury?
Did the child experience any pre-seizure symptoms, like an “aura” (a specific sensation or feeling that precedes a seizure)?
Seizure Characteristics:
Onset: Was the onset focal (e.g., eye or head turning to one side, twitching on one side of the body) or generalized?
Motor Activity: Describe any stiffening, jerking, or twitching of the face or body.
Consciousness: Was the child responsive during the seizure? Did they make any sounds?
Associated Features: Note any changes in breathing, skin color (cyanosis or paleness), incontinence, or a tongue bite.
Post-Seizure (Post-Ictal) Details:
How long did the child remain confused, drowsy, or weak after the event?
Other Important Factors:
Ask about any recent illnesses, head trauma, or fluid balance issues.
Inquire about any headaches, vomiting, or weakness.
Review the child’s developmental milestones and any history of learning or behavioral difficulties.
Document the family history of seizures, epilepsy, fainting, heart rhythm problems, or sudden death.
Examination
A focused physical and neurological examination helps identify signs of an underlying cause.
General Assessment: Check the child’s level of consciousness, monitor their GCS, and measure head circumference in children under 3 years old.
Look for Dysmorphic Features: Identify any signs of dysmorphism or neurocutaneous syndromes (e.g., café-au-lait spots, which are linked to neurofibromatosis).
Neurological Exam: Perform a thorough neurological assessment, including a cranial nerve exam and, if possible, fundoscopy to check for signs of increased intracranial pressure (ICP) like papilloedema.
When to Admit to the Hospital
Not all children with an afebrile seizure need to be admitted. A child should be admitted or observed if they are:
Unwell or if meningitis/raised ICP is suspected.
Under 18 months of age.
Have had a prolonged, multiple, or focal seizure.
Have a Glasgow Coma Scale (GCS) of less than 15, even one hour after the seizure.
Show new neurological signs.
There is high parental anxiety.
If the patient is known to have epilepsy, check for a likely explanation (e.g., inter-current illness or non-compliance with medication) or if the child has outgrown their dosage.
Initial Investigations
ECG: An electrocardiogram (ECG) is performed in all children with a motor seizure to check for heart rhythm abnormalities that could mimic a seizure.
Blood Glucose: A blood glucose test is essential if the child is still seizing or not fully alert.
Other Lab Tests
Blood tests (including FBC, U&E, blood glucose, bone profile, Mg, CRP) and urine analysis should be considered in children with an illness, those under 18 months, or those who had prolonged or multiple seizures.
Lumbar Puncture
A lumbar puncture (LP) should be considered to check for meningitis, especially in children under 18 months who may not show classic signs. LP is contraindicated if the child has signs of increased ICP, septic shock, or a focal neurological deficit.
EEG (Electroencephalogram)
An EEG is not always required after a first simple afebrile seizure. It is most useful for differentiating between focal and generalized seizures and guiding the decision to start medication. However, remember that a normal EEG does not rule out epilepsy.
Neuroimaging
Neuroimaging is not routinely needed for all children.
A CT scan may be used to investigate acute neurological issues like a brain injury or a suspected tumor.
An MRI is the preferred method for more detailed imaging and is considered in children under 2 with recurrent seizures, those with focal features, poor seizure control on medication, or an underlying neurodevelopmental disorder.
Diagnosis and Follow-Up
At the end of the assessment, the working diagnosis is typically one of the following:
Epileptic Episode: If it’s a first-time single seizure, treatment is generally not started right away. The family is given a safety plan, a diary to record any future events, and a follow-up appointment is arranged.
Acute Symptomatic Seizure: The underlying cause is investigated and treated accordingly.
Non-Epileptic Event: The likely diagnosis is discussed, and the family is advised on the next steps.
A child who has fully recovered with normal vitals can be discharged after thorough parental counseling.
Emergency Advice
If a child has a history of prolonged or recurrent seizures, parents should be advised to call an ambulance after 5 minutes of a seizure and may be provided with rescue medication like buccal Midazolam.
Outlook
While a first afebrile seizure is alarming, many children do not have another. About 30-50% will have a recurrence within two years. The risk of recurrence is higher after a second unprovoked seizure, at 70-80%.