Etiologies and Diagnostic Approaches for Seizures in Young Patients

Age-Dependent Etiology Patterns

Hypoxic-ischemic encephalopathy dominates as the primary cause of seizures in neonates, accounting for 46-65% of cases, with 90% occurring within the first 2 days of life 1, 2, 3
Intracranial hemorrhage and perinatal ischemic stroke combined represent 10-12% of seizure cases in neonates 2, 3
Metabolic derangements, including hypoglycemia, are critical treatable causes of seizures in neonates 1, 3
In older children and adolescents, idiopathic/unknown etiology represents 27-44% of seizure cases 4, 5
Drug toxicity and intoxication become increasingly relevant causes of seizures in older children and adolescents 4

Point-of-care glucose testing is mandatory to exclude hypoglycemia immediately in seizure patients 1, 3
Electrolyte abnormalities require urgent assessment, as 8% of seizure patients have correctable metabolic abnormalities 5
For neonates, systematic evaluation identifies the underlying cause of seizures in approximately 95% of cases 1, 2
MRI with diffusion-weighted imaging is the gold standard for identifying the etiology of seizures in neonates 1, 3

In alcohol-related seizures, clinicians must eliminate symptomatic causes before labeling as withdrawal seizures 6, 5
Brief myoclonic movements do not confirm epileptic seizures; distinction depends on synchrony, rhythmicity, and number of movements 1
History and physical examination fail to predict metabolic abnormalities in approximately 2-3 cases per 100 seizure patients 4, 5
In HIV-positive patients with new-onset seizures, 40% have acute lesions necessitating admission 7
Febrile patients have a 55% likelihood of CNS infection if presenting with seizures 4
Blood culture, urine culture, and empirical antibiotics should be initiated immediately when infection is suspected in seizure patients 1, 3