Neonatal Seizures and Crying
Neonatal seizures do not typically involve crying during or after the ictal event; in fact, the absence of crying or vocalization is a distinguishing feature that helps differentiate true seizures from other paroxysmal movements in newborns. 1
Why Crying is Absent During Neonatal Seizures
The clinical manifestations of neonatal seizures are fundamentally different from seizures in older children and adults due to the developmental immaturity of the neonatal brain. 1, 2 Key distinguishing features include:
Electroclinical dissociation is an outstanding feature of neonatal seizures, meaning motor phenomena that appear seizure-like may not have EEG correlates, while true electrographic seizures frequently occur without any identifiable clinical symptoms. 3
Subtle or absent clinical signs are characteristic—neonatal seizures present a unique diagnostic challenge because manifestations are often subtle or completely absent to the bedside observer. 1
Reliable diagnosis requires continuous EEG monitoring, which is the gold standard, because clinical observation alone is insufficient. 3, 1, 4
When Crying Does Occur in Neonates: Alternative Diagnoses
If a neonate presents with excessive or high-pitched crying, consider these alternative etiologies rather than seizures:
Neonatal Withdrawal Syndromes
- High-pitched crying is a hallmark of opioid withdrawal, along with tremors, irritability, increased wakefulness, and increased muscle tone—not seizures themselves. 5
- Opioid withdrawal occurs in 55-94% of exposed neonates, with onset typically 24-72 hours after birth but potentially delayed up to 5-7 days. 5, 6
- While seizures can occur in 2-11% of infants withdrawing from opioids, the crying itself is a manifestation of CNS irritability, not the seizure. 5
Metabolic Derangements
- Hypoglycemia, hypocalcemia, and hypomagnesemia cause excessive crying and jitteriness that require immediate reversal. 6, 7
- These metabolic causes should be tested immediately with serum glucose, calcium, and magnesium. 6, 7
Normal Developmental Crying
- Crying peaks between 2-4 months of age as part of normal development, making a 2-week-old infant at the early phase of this curve. 6, 8
Critical Diagnostic Pitfall
Do not mistake jitteriness for seizures. Jitteriness differs from seizures by being stimulus-sensitive, ceasing with passive flexion of the affected limb, having no abnormal eye movements or autonomic changes, and predominantly affecting limbs rather than face. 7 True neonatal seizures are defined as repetitive, evolving, stereotyped electrographic events lasting at least 10 seconds with amplitude of at least 2 μV. 4
When to Suspect True Neonatal Seizures
High-risk populations that warrant continuous EEG monitoring include:
- Hypoxic-ischemic encephalopathy (46-65% of neonatal seizures), with 90% experiencing seizure onset within 2 days after birth. 5
- Intracranial hemorrhage and perinatal ischemic stroke (10-12% of cases). 5
- Infection, genetic disorders, or malformations of cortical development if seizures occur beyond the seventh day of life. 5