What is the initial treatment for an infant presenting with infantile spasms and neurostorming, specifically regarding the use of steroids like prednisolone?

Initial Treatment for Infantile Spasms and Neurostorming

For an infant presenting with infantile spasms, initiate high-dose oral prednisolone at 40-60 mg/day (or 8 mg/kg/day) as first-line hormonal therapy, administered as a single morning dose for 2 weeks, followed by a taper over 5 weeks. 1, 2 For neurostorming (autonomic storming), steroids are not the primary intervention—focus on benzodiazepines, propranolol, and environmental control first.

Infantile Spasms: Steroid Protocol

First-Line Hormonal Treatment

• Start high-dose oral prednisolone at 40-60 mg/day (approximately 8 mg/kg/day) as a single morning dose 1, 2
• This dosing is significantly higher than standard pediatric corticosteroid dosing and is specific to infantile spasms 2
• Administer for 2 weeks at full dose, then taper over 5 weeks 1
• Electroclinical response (spasm cessation and hypsarrhythmia resolution) occurs in 64% of infants within 2 weeks 2

Evidence Supporting Prednisolone as First-Line

• Prednisolone achieves spasm cessation in 63% of infants as first-line treatment, significantly superior to vigabatrin (28%) or nonstandard treatments (5.9%) 3
• The UK Infantile Spasms Study demonstrated that hormonal treatments (prednisolone or tetracosactide) achieved spasm cessation in 73% versus 54% with vigabatrin 4
• High-dose oral prednisolone is less expensive and more readily available than intramuscular ACTH, with comparable efficacy 2

Sequential Treatment Algorithm if Prednisolone 40 mg/day Fails

If no response after 2 weeks at prednisolone 40 mg/day:

1. Escalate to prednisolone 60 mg/day - achieves response in 41% of initial non-responders 3
2. If still no response, switch to vigabatrin - achieves response in 45% of prednisolone non-responders 3
3. Consider ACTH only after both prednisolone doses and vigabatrin have failed 5

• The UKISS treatment sequence (prednisolone 40 mg → prednisolone 60 mg → vigabatrin) achieves overall treatment response in 83% of infants 3

Critical Monitoring During Treatment

Monitor closely for these specific adverse effects:

• Irritability, weight gain, and gastroesophageal reflux occur in 52% of patients 2
• Major adverse events (5% incidence): gastrointestinal bleeding, herpes simplex virus reactivation, necrotizing enterocolitis 2
• Adverse events are common with both hormonal treatments (55%) and vigabatrin (54%), with no significant difference in severe side effects between treatments 4, 3

Special Consideration for Perinatal Stroke

• For infantile spasms secondary to perinatal stroke, high-dose prednisolone at 8 mg/kg/day is particularly effective, with spasm cessation after the first dose in documented cases 1
• Modified hypsarrhythmia should be confirmed on video-EEG before initiating treatment 1

Neurostorming (Autonomic Storming): Steroid Role

Primary Management (Not Steroids)

Steroids are NOT first-line for neurostorming. The primary interventions are:

• Benzodiazepines for acute episodes
• Propranolol (non-selective beta-blocker) for autonomic stabilization
• Environmental control: minimize stimulation, maintain quiet environment
• Treat underlying triggers: pain, infection, constipation, bladder distension

When to Consider Steroids for Neurostorming

Steroids may have a role only if:

• There is concurrent cerebral edema requiring treatment
• Inflammatory CNS pathology is driving the autonomic instability
• This is NOT standard practice and should be guided by neurocritical care consultation

Critical Pitfalls to Avoid

• Do NOT use standard pediatric steroid dosing (1-2 mg/kg/day) for infantile spasms - this is inadequate; use 8 mg/kg/day or 40-60 mg/day absolute dose 1, 2
• Do NOT start with vigabatrin as first-line unless there is tuberous sclerosis (where vigabatrin is preferred) 4, 3
• Do NOT confuse neurostorming with seizures - they require different management approaches
• For infantile spasms with cardiomyopathy risk, consult cardiology before initiating steroids 6
• Ensure varicella immunity is established before starting steroids 6

Practical Administration Details

• Administer prednisolone before 9 AM as a single morning dose to minimize HPA axis suppression 7, 8
• Use liquid formulation if available for better absorption 9
• No tapering required if treatment duration is under 7 days, but infantile spasms protocols require 7 weeks total (2 weeks full dose + 5 weeks taper) 9, 1
• Provide families with a steroid card listing emergency considerations for acute illness, surgery, or trauma 6