Table 5.

Biochemical testing in common disorders

Testing parameter	Disorders
Creatine phosphokinase (Serum)	Muscular dystrophies Merosin deficient congenital muscular dystrophy Dystroglycanopathies
Lactate, pyruvate (Plasma, Cerebrospinal fluid)	Mitochondrial disorders
Glycosaminoglycans (Urine)	Metachromatic leukodystrophy Multiple sulfatase deficiency
Organic acids (Urine)	L-2-hydroxyglutarate N-acetylaspartic acid for Canavan disease Metabolic disorders of Krebs cycle Other mitochondrial disorders
Amino acids (Urine)	Aminoacidopathies Maple syrup urine disease Homocystinuria Hyperornithinemia-hyperammonemia-homocitrullinemia syndrome Pyruvate dehydrogenase complex deficiency
Very long chain fatty acids (Plasma)	Peroxisomal disorders X-linked adrenoleukodystrophy
Lysosomal enzymes (leukocytes/fibroblasts)	Krabbe (galactosyl cerebrosidase) Metachromatic leukodystrophy (arylsulfatase A) Multiple sulfatase deȴciency (arylsulfatase A,B,C,D) GM1 gangliosidosis (beta galactosidase) GM2 gangliosidosis (hexosaminidase A & B) Sialidosis (neuraminidase) Galactosialidosis (neuraminidase and beta galactosidase)
1,4-alpha-glucan-branching enzyme activity	Adult polyglucosan body disease
Cholestanol	Cerebrotendinous xanthomatosis
Fatty aldehyde dehydrogenase enzyme	Sjogren-Larsson syndrome