Neonatal Jitteriness: Clinical Description and Management
Jitteriness in a newborn is a benign, involuntary tremor movement that typically resolves spontaneously by 7-9 months of age and carries an excellent prognosis, but requires immediate evaluation to exclude treatable metabolic causes, particularly hypoglycemia and hypocalcemia. 1, 2
Core Clinical Features
Jitteriness is characterized by:
- Involuntary tremor movements that are the hallmark finding 1
- Frequently accompanied by hypermotility, hypertonicity, and exaggerated startle response 1
- Can be stimulus-sensitive and typically stops with gentle flexion or holding of the affected limb (distinguishing it from seizures) 1
- "Coarse" tremor patterns are more concerning than "fine" tremor and may correlate with later choreiform movement disorders 1
Essential Differential Diagnosis
Critical distinction from seizures:
- Jitteriness lacks the autonomic changes (apnea, bradycardia, pupillary changes) seen with seizures 1
- Jitteriness movements can be suppressed by passive flexion, whereas seizure activity cannot 1
- Myoclonus may coexist with jitteriness, complicating the clinical picture 1
Immediate Evaluation Required
Metabolic workup must include:
- Serum glucose (hypoglycemia is a common provoked cause) 3
- Serum calcium and magnesium (hypocalcemia causes provoked seizures and jitteriness) 3
- Electrolytes including sodium, potassium, and phosphorus 4
- Hematocrit 4
Medication exposure history:
- Maternal SSRI use (causes neonatal withdrawal with tremors, irritability, poor feeding within hours to days, lasting 1-4 weeks) 3
- Maternal benzodiazepine or clonazepam use (withdrawal tremors appear hours to weeks after birth, potentially lasting 1.5-9 months) 3, 5
- Maternal opioid use (55-94% of exposed neonates develop neonatal abstinence syndrome) 3
- Maternal caffeine consumption (causes jitteriness, vomiting, bradycardia, tachypnea at birth, lasting 1-7 days) 3
Natural History and Prognosis
Timeline of resolution:
- Most cases resolve by mean age of 7.2 months (±3.4 months) 2
- 81% of otherwise healthy term infants have complete resolution by 9 months 6
- Only 11% persist beyond 1 year of age 6
- Infants with mild associated neurological findings (mild hypertonicity, hyperreflexia) resolve faster (mean 5.5 months) compared to moderate-to-severe findings (mean 9.5 months) 6
Developmental outcomes:
- 92% of infants with isolated jitteriness beyond the neonatal period have completely normal neurodevelopmental examinations at 3 years 2
- The remaining 8% show only minor, transient disturbances 2
- Motor delay requiring physiotherapy occurs in only approximately 3% of cases 6
Pathophysiology
Underlying mechanisms:
- Elevated norepinephrine levels (1276 ±574 vs 914 ±338 in controls, p<0.05) indicate increased sympathetic activity in jittery neonates 4
- Likely represents a maturational process within the central nervous system 2
- Intracranial hemorrhage is not a cause in otherwise healthy term infants 4
Management Approach
Treatment priorities:
- Reverse any identified metabolic derangements immediately (hypoglycemia, hypocalcemia, hypomagnesemia) 3, 1
- Manage neonatal drug withdrawal syndromes if maternal substance exposure is confirmed 3
- Reassure parents about the benign nature and excellent prognosis when metabolic causes are excluded 2, 6
- Follow at 3-month intervals until complete resolution 6
- Reserve neuroimaging and EEG for cases with focal neurologic findings, seizure concern, or atypical features 3
Common pitfall: Confusing jitteriness with seizures leads to unnecessary anticonvulsant therapy. The key distinguishing feature is that jitteriness stops with passive restraint and lacks autonomic changes. 1