What is the appropriate diagnosis and management for a pediatric patient presenting with a febrile seizure?

Febrile Seizure Diagnosis and Management

Febrile seizures are diagnosed clinically in children aged 6 months to 5 years presenting with a generalized seizure accompanied by fever (≥100.4°F/38°C) without evidence of intracranial infection, metabolic disturbance, or history of afebrile seizures, and the vast majority require no diagnostic testing or long-term treatment. 1

Classification

Febrile seizures must be classified as either simple or complex, as this determines the diagnostic approach:

Simple febrile seizures are characterized by:

• Generalized (not focal) seizure activity 1, 2
• Duration less than 15 minutes 1, 2
• Single episode within 24 hours 1, 2
• Temperature ≥100.4°F (38°C) 1
• No intracranial infection present 1

Complex febrile seizures have one or more of the following features:

• Duration ≥15 minutes 3, 1
• Focal neurologic findings 3, 1
• Recurrence within 24 hours 3, 1

Diagnostic Evaluation

Simple Febrile Seizures

For well-appearing children with simple febrile seizures, routine diagnostic testing is explicitly NOT indicated. 1, 2 This includes:

• No neuroimaging (CT or MRI) required 1, 4
• No EEG indicated 1
• No routine laboratory tests needed 1, 2

The only diagnostic workup necessary is to identify the source of fever (e.g., otitis media, viral illness, urinary tract infection). 1, 2

Critical exception: Children under 12 months of age with fever and seizure should undergo lumbar puncture to rule out meningitis, as meningeal signs may be absent in up to one-third of cases. 1

Complex Febrile Seizures

Neuroimaging is generally NOT indicated for complex febrile seizures unless specific concerning features are present. 3, 4

Consider MRI only when:

• Postictal focal neurological deficits persist 3, 4
• Febrile status epilepticus occurred (seizure lasting >30 minutes) 3
• Underlying pathology such as meningitis, encephalitis, or trauma is clinically suspected 3

Important caveat: Analysis of 161 children with complex febrile seizures showed head CT revealed no findings requiring intervention. 3, 4 Even when imaging abnormalities are detected (14.8% in complex vs. 11.4% in simple febrile seizures), these findings do not alter clinical management. 3, 4

Acute Management

During the Seizure

• Position the patient on their side and protect the head from injury 1
• Remove harmful objects from the environment 1
• Never restrain the patient or place anything in the mouth 1, 4

Prolonged Seizures (>5 minutes)

First-line treatment: Lorazepam 0.05-0.1 mg/kg IV (maximum 4 mg) given slowly at 2 mg/min 1, 2

Alternative routes when IV access unavailable:

• Rectal diazepam 4
• Buccal midazolam 1

When to Activate Emergency Services

Call 911 for:

• First-time seizures 4
• Seizures lasting >5 minutes 4
• Multiple seizures without return to baseline 4
• Breathing difficulties or choking 4

Long-Term Management

The American Academy of Pediatrics explicitly recommends AGAINST both continuous and intermittent anticonvulsant prophylaxis for children with simple febrile seizures. 1, 4 This recommendation is based on high-quality evidence (randomized controlled trials) showing that potential toxicities clearly outweigh the minimal risks. 1

Why No Prophylaxis?

The harm-benefit analysis strongly favors no treatment:

Valproic acid risks:

• Rare fatal hepatotoxicity (especially in children <2 years) 1
• Thrombocytopenia 1
• Pancreatitis 1

Phenobarbital risks:

• Hyperactivity and irritability in 20-40% of patients 1
• Mean IQ reduction of 7 points during treatment 1
• Cognitive effects persisting 5.2 points lower even 6 months after discontinuation 1

Intermittent diazepam risks:

• Lethargy and drowsiness 1
• May mask evolving CNS infection 4

Role of Antipyretics

Antipyretics (acetaminophen, ibuprofen) do NOT prevent febrile seizures or reduce recurrence risk. 1, 4, 2 They should be used for the child's comfort and to prevent dehydration, but not for seizure prevention. 1, 4

Prognosis and Parent Education

Simple febrile seizures have an excellent prognosis with no long-term adverse effects. 1

Key counseling points:

• No decline in IQ, academic performance, or neurocognitive function 1
• No structural brain damage 1
• Risk of developing epilepsy by age 7 is approximately 1% (identical to general population) 1
• Even high-risk children (multiple seizures, age <12 months at first seizure, family history of epilepsy) have only 2.4% risk of epilepsy by age 25 1

Recurrence Risk

• Children <12 months at first seizure: approximately 50% recurrence probability 1
• Children >12 months at first seizure: approximately 30% recurrence probability 1
• Of those with a second febrile seizure, 50% have at least one additional recurrence 1

Recurrent simple febrile seizures cause no harm and do not warrant prophylactic treatment. 1

When to Refer to Neurology

Neurological consultation should be requested for:

• Prolonged febrile seizures 1
• Repetitive focal febrile seizures 1
• Abnormal neurological exam or development 1
• First antiepileptic medication failure (if true epilepsy develops) 1

Common Pitfalls to Avoid

• Do not order routine neuroimaging for simple or complex febrile seizures unless focal deficits or concern for intracranial pathology exists 3, 4
• Do not prescribe prophylactic anticonvulsants for simple febrile seizures—the AAP guideline is unequivocal on this point 1, 4
• Do not assume antipyretics prevent seizures—they provide comfort only 1, 4
• Do not delay antibiotics for diagnostic procedures when bacterial meningitis is suspected with a non-blanching rash 5