• Complete blood cell count, electrolytes, calcium, magnesium
  • Glucose
  • Ammonia, uric acid
  • Biotinidase
  • Liver function tests, ammonia
  • Lactic acid, pyruvic acid
  • Acylcarnitines, amino acids


  • Organic acids, mucopolysaccharides
  • Sialic acid, oligosaccharides
  • Purines and pyrimidines

Cerebrospinal fluid

  • Glucose, protein, cells
  • Catecholamines


  • Electroencephalography (EEG)
  • Evoked potentials
  • Electromyography
  • Sensory and motor nerve conduction


  • Brain magnetic resonance imaging (MRI)

Tissue biopsies

  • Skin
  • Muscle

Adapted from: Kolodny, EH. Metabolic and genetic disorders. In: Devinsky O and Westbrook LE, eds. Epilepsy and Developmental Disabilities. Boston: Butterworth-Heinemann; 2001;17-22.
With permission from Elsevier (

Authored By: 
EH Kolodny
Reviewed By: 
Steven C. Schachter MD
Monday, March 1, 2004