Neurology · Year 3 · from Neurology

Case 1: Infantile Spasms (West Syndrome)

Patient Demographics

  • Age: 6 months old
  • Sex: Male
  • Parents: Both present, first-time parents

Chief Complaint

Mother: "He's been having these strange jerking movements where he curls up. They happen in clusters when he wakes up."

History of Present Illness

Baby Lucas is a 6-month-old boy brought by his parents for evaluation of unusual movements that began 2 weeks ago. His mother describes episodes where he suddenly flexes his body - his arms come up, his head drops forward, and his legs draw up toward his belly - like he is "folding in half." Each jerk lasts about 1-2 seconds. The movements occur in clusters of 10-20 episodes over several minutes, typically right after waking from sleep. The parents initially thought he had colic or gas, but the episodes have increased in frequency and they noticed he seems distressed during them, sometimes crying afterward. Between episodes, he appears normal. They have also noticed he seems less interactive than he was a month ago - he used to smile and coo at them frequently, but now he seems more "zoned out."

Developmental History

  • 3 months: Social smile, cooing, head control - ALL ON TIME
  • 5 months: Reaching for objects, rolling front to back - ON TIME
  • 6 months (now): Parents report he seems to have "lost" his social smile and is less engaged; not reaching as much

Birth History

  • Born at 39 weeks via uncomplicated vaginal delivery
  • Birth weight: 7 lbs 4 oz
  • APGAR scores: 8 and 9
  • No NICU admission
  • Normal newborn metabolic screen
  • No hypoxic episodes

Past Medical History

  • No significant medical problems
  • No prior seizures
  • Immunizations up to date

Family History

  • No seizure disorders
  • No neurocutaneous syndromes
  • No developmental delays

Physical Examination

  • Vital Signs: Normal for age
  • Growth: Weight and head circumference at 50th percentile
  • General: Alert infant, less socially engaged than expected
  • Skin: Examined carefully under Wood's lamp - 3 hypopigmented macules ("ash leaf spots") on trunk, approximately 1-2 cm each
  • Neurological:
  • Hypotonia noted (mild axial)
  • No focal deficits
  • Deep tendon reflexes normal
  • During examination: Witnessed cluster of 8 flexor spasms over 2 minutes following arousal - flexor spasms with arm extension (modified salaam attack)

Clinical Image

Image: Illustration showing the characteristic flexor spasm pattern in infantile spasms (West syndrome) with sudden flexion of trunk, arms, and legs in a "jackknife" or "salaam" posture.

Image Source: Wikimedia Commons Attribution: Medical illustration, Educational Use URL: https://commons.wikimedia.org/wiki/File:Infantile_spasms.png

Diagnostic Studies

EEG:

  • Hypsarrhythmia: High-amplitude chaotic background with multifocal spikes and slow waves - classic pattern for infantile spasms
  • Recorded one cluster of electrodecremental events (EEG flattening) corresponding to clinical spasms

MRI Brain:

  • Multiple cortical tubers (hyperintense T2/FLAIR lesions) in bilateral cerebral hemispheres
  • Subependymal nodules along lateral ventricles
  • No subependymal giant cell astrocytoma (SEGA)

Genetic Testing:

  • TSC1/TSC2 gene analysis sent

Additional Workup:

  • Echocardiogram: No cardiac rhabdomyomas
  • Renal ultrasound: Small bilateral renal cysts
  • Ophthalmology: Retinal hamartomas present

Assessment and Diagnosis

  1. Infantile Spasms (West Syndrome)
  • Clinical: Clusters of flexor spasms
  • EEG: Hypsarrhythmia
  • Developmental regression
  1. Tuberous Sclerosis Complex (TSC)
  • Definite diagnosis based on meeting clinical criteria:
  • Major features: Cortical tubers (2), ash-leaf spots (≥3), subependymal nodules, retinal hamartomas
  • Minor features: Renal cysts
  • Genetic confirmation pending

Diagnostic Criteria - West Syndrome (Triad)

FeaturePresent
Infantile spasms (clusters)YES
Hypsarrhythmia on EEGYES
Developmental regressionYES

Urgency of Treatment

Infantile spasms constitute a neurological emergency - prompt treatment is associated with better developmental outcomes. Delay in treatment is associated with poorer cognitive outcomes.

Management Plan

First-Line Treatment for Infantile Spasms in TSC:

  • Vigabatrin 50 mg/kg/day divided twice daily
  • Increase to 100-150 mg/kg/day over 1-2 weeks based on response
  • Vigabatrin is specifically preferred in TSC-associated infantile spasms (higher response rate than ACTH)
  • Counsel on retinal toxicity risk - requires baseline and periodic ophthalmology monitoring

If Vigabatrin Fails or for Non-TSC Infantile Spasms:

  • ACTH (adrenocorticotropic hormone) - traditional first-line
  • High-dose prednisolone as alternative

TSC-Specific Management:

  • Referral to comprehensive TSC clinic
  • mTOR inhibitor therapy (everolimus) - may be considered for SEGA prevention
  • Multidisciplinary surveillance per TSC guidelines:
  • MRI brain annually until age 25 (SEGA surveillance)
  • Renal imaging every 1-3 years
  • Echocardiogram follow-up
  • Developmental monitoring
  • Ophthalmology annually

Developmental Services:

  • Early intervention referral
  • Physical therapy
  • Occupational therapy

Follow-Up (2 weeks after starting vigabatrin)

Clinical Response:

  • Spasm frequency reduced by >90%
  • Only 1-2 isolated spasms per day (from 20-30 daily)
  • Parent report improved alertness and eye contact

Repeat EEG:

  • Resolution of hypsarrhythmia
  • Mild background slowing (expected)
  • No electroclinical spasms captured

Vigabatrin dose: Increased to 100 mg/kg/day

Follow-Up (3 months)

  • Spasms completely resolved
  • Developmental trajectory improving - regaining social smile
  • EEG: No hypsarrhythmia, focal epileptiform discharges from tuber regions
  • Ophthalmology (baseline): No visual field deficits
  • Genetic testing confirmed: Pathogenic TSC2 mutation

Teaching Points

  1. Infantile spasms (West syndrome) is a neurological emergency - early treatment improves outcomes
  1. Classic triad: Infantile spasms + hypsarrhythmia + developmental regression
  1. Spasms typically occur in clusters upon awakening - flexor or extensor
  1. Always examine skin under Wood's lamp - ash-leaf spots suggest TSC
  1. Vigabatrin is first-line for TSC-associated infantile spasms (>90% response rate)
  1. ACTH is first-line for non-TSC infantile spasms
  1. TSC requires multisystem surveillance - brain, kidneys, heart, skin, eyes
  1. Prognosis: Unfortunately, many children with infantile spasms (especially with underlying etiology) have developmental disabilities

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