Early Infantile Epileptic Encephalopathy (EIEE)

Definition

• Epilepsy: Seizure disorder.
• Encephalopathy: Brain dysfunction, often due to damage.
• Early Infantile: Onset within the first three months of life.

Characteristics

• EIEE: Recurrent and unprovoked seizures during early infancy leading to severe brain damage.

Nervous System Basics

• Neurons: Specialized cells that receive and send signals.
• Synapse: Point where neurons communicate via neurotransmitters.
• Excitatory Neurotransmitters: e.g., Glutamate, open ion channels, relay signals.
• Inhibitory Neurotransmitters: e.g., GABA, close ion channels, dampen signals.

Causes of EIEE

• Structural Brain Abnormalities:
  • Hemi-megalencephaly
  • Absence of corpus callosum
  • Abnormal cerebral cortex development
• Metabolic Disorders:
  • Nonketotic hyperglycemia
• Genetic Mutations:
  • ARX (Aristaless-related homeobox)
  • STXBP1 (Syntaxin-binding protein 1)
• Impact: Defective neurons fire excessively and synchronously, causing seizures.

Clinical Presentation

• Onset: First 3 months of life, often within 10 days.
• Types of Seizures:
  • Generalized tonic-clonic
  • Myoclonic seizures
• Frequency: Up to 100 seizures per day.
• Duration: Less than 10-20 seconds per seizure.

Mechanism

• Repeated neuron firing alters synapses, disrupting impulse conduction.
• Affects memory and learning areas.
• Leads to severe impairment and developmental delays (e.g., sitting, babbling).

Diagnosis

• Electroencephalography (EEG):
  • Detects burst suppression patterns.
  • Frequent EEG abnormalities between seizures impair development.
• Brain Imaging: MRI for structural abnormalities.
• Blood Tests: Detect metabolic/genetic disorders.

Treatment

• Challenges: Seizures hard to control, often unresponsive to antiseizure meds.
• Corticosteroid Therapy: Prednisolone or ACTH.
• Ketogenic Diet: Uses fat instead of carbs for energy.
• Underlying Cause: Correction helps reduce seizures where possible.

Prognosis

• Severe prognosis:
  • High mortality within first 2 years.
  • Survivors have severe disabilities.
• Syndrome Transition:
  • Potential transition to West syndrome, Lennox-Gastaut syndrome.

Summary

• EIEE is characterized by early-onset seizures leading to significant brain damage.
• Typical presentation on EEG and frequent seizures.
• Limited treatment options, poor overall prognosis.