See also

Sepsis
Adrenal crisis/insufficiency

Key points

1. Infantile spasms (IS) are a type of seizure, and are the most common severe epilepsy in infants
2. IS are typically sudden, brief, bilateral and symmetric contraction of the muscles of the neck, trunk and extremities, occurring in clusters
3. IS are often the presenting feature of a significant underlying neurological disorder
4. Prompt diagnosis and treatment are critical to minimise the developmental impacts
5. First-line treatment is usually high dose prednisolone
6. High dose prednisolone may mask responses to infection, including fever. Signs of sepsis in a child on high dose prednisolone should be managed as per the S­­epsis CPG

Background

• Peak age of IS onset is 3 to 7 months
• IS typically occur in the context of West syndrome (WS), characterised by the triad of IS, hypsarrhythmia on EEG and developmental arrest/regression.
• Not all children with IS have all features of WS
• Common causes of IS include tuberous sclerosis complex (TS), trisomy 21, focal structural abnormality, perinatal HIE
• IS are associated with developmental delay in over 80% of infants, and high rates of ongoing epilepsy
• Prompt treatment is required to minimise the adverse developmental impact. High dose prednisolone is first-line treatment for most infants; vigabatrin is first-line in infants with TSC

Assessment

1. Are the infant’s episodes IS?
Features suggestive of IS

• Occur in clusters, most commonly shortly after waking from sleep
• Typically sudden flexor or extensor spasms of the whole body
• May be more subtle - head nodding or facial or eye movements
• May be asymmetric
• Review parental video recordings of the episodes if available

Differential diagnosis:

• Non-epileptic episodes such as shuddering and benign myoclonus of infancy
• Benign myoclonic epilepsy of infancy
• Other infantile epilepsies

2. What is the underlying cause for IS?
Features that provide potential clues to the underlying cause

• Pre-existing condition known to be associated with IS (eg TSC, trisomy 21)
• Family history of seizure disorder or developmental delay (genetic basis)
• Early handedness (focal structural abnormality)
• Dysmorphic features or congenital anomalies (chromosomal abnormality)
• Skin lesions (eg hypopigmented macules of TSC)
• Pre-existing developmental delay
• Neonatal or early infantile seizures
• Head circumference growth

Management

• Neurological consultation is mandatory for children with suspected IS
• Admission is recommended for confirmation of IS with EEG, investigation of aetiology, and commencement of treatment

Investigations

• Urgent awake and sleep EEG
• Prompt MRI brain
• Other investigations for underlying aetiology (if unknown), including chromosomal microarray, urine metabolic screen and consideration of other genetic testing

Treatment

Neurology team should determine appropriate treatment

• High dose prednisolone is first-line treatment (except for TS and treatable metabolic conditions)
• Prednisolone 10 mg QID for 1 week then:
  • If spasms cease during this week, continue 10 mg QID for 1 more week, then wean off 10 mg every 5 days (ie TDS to BD to once daily then cease) for a total 4 weeks treatment
  • If spasms continue after week 1 of treatment, the prednisolone dose should be increased to 20 mg TDS for 1 week (then wean to 10 mg QID, then BD to once daily and then cease)
  • Vigabatrin is second-line treatment after 2 weeks of inadequate response to corticosteroids, and should be added to the weaning prednisolone regimen.
• Vigabatrin is recommended as first line treatment in TSC
• First-line treatment with combination prednisolone and vigabatrin has a higher rate of spasm cessation but showed no improvement in developmental outcome at age 18 months over prednisolone alone. Also, vigabatrin is associated with potential ocular and neurologic side effects. Thus, it has not superseded prednisolone monotherapy as standard practice, although may be considered on a case-by-case basis

Precautions and monitoring while taking prednisolone:

• High dose prednisolone treatment is associated with increased risk of serious +/or opportunistic infections
  • Any child with IS on prednisolone who presents febrile or unwell should be admitted and managed as per the Sepsis Guideline. Consider infectious disease consultation
  • If there is vomiting or significant diarrhoea, administer IV/IM hydrocortisone
• Prophylactic trimethoprim-sulfamethoxazole for infection prevention
• Monitor BP, blood glucose and weight twice weekly
• Vaccines should be delayed until one month after ceasing prednisolone. See Victorian Immunisation Handbook

Consider consultation with local paediatric team when

All children with suspected IS

Consider transfer when

• Urgent EEG, prompt MRI and neurology consultation are unavailable
• Consider transfer of unwell child if requiring care beyond the comfort level of the hospital

For emergency advice and paediatric or neonatal ICU transfers, see Retrieval Services.

Consider discharge when

• Child has follow-up arranged with neurologist, or paediatrician with input from a neurologist, and a follow-up EEG booked (after two weeks).
• Admission for IS diagnosis and initial management is usually brief, and discharge is not dependent on spasm cessation

The Steroid Alert Card should be given to parents prior to hospital discharge regarding treatment in the event of becoming unwell or febrile

Parent information sheet

• Infantile Spasms prednisolone treatment parent information
• Infantile Spasms Steroid Alert Card
• Kids Health Info - Epilepsy

Last Updated May 2020