Amino acids
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PSAT deficiency
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CSF amino acids (& PAA)
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PSPH deficiency (Serine deficiency)
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CSF amino acids (& PAA)
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Late onset non-ketotic hyperglycinemia
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CSF AA (& Plasma AA)
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PHGDH deficiency (Serine deficiency)
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CSF AA (& Plasma AA)
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Cerebral glucose transport
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Blood brain-barrier glucose-transporter (GLUT1) defect
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CSF glucose:plasma glucose ratio
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Creatine
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Arginine: glycine amidinotransferase (AGAT) deficiency
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GATM gene sequencing
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Creatine transporter deficiency
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SLC6A8 gene sequencing
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Lipids
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Abetalipoproteinemia
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CBC smear, stool samples, fasting lipid profile, MTTP gene analysis
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Lysosomal
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Krabbe disease
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WBC enzyme testing
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Metachromatic leucodystrophy (MLD)
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Arylsulfatase-A enzyme activity
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Niemann-Pick, type C
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Filipin staining test (fibroblasts) & NPC1/NPC2 gene analyses
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Mitochondria
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Coenzyme Q10 deficiency
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Coenzyme Q10 (fibroblasts) & gene(s) analysis
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MELAS
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Mitochondrial DNA mutation testing
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Pyruvate dehydrogenase deficiency
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Blood & CSF lactate:pyruvate ratio (enzyme activity, gene(s) analysis)
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Neurotransmission
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Aromatic-L-amino-acid decarboxylase deficiency
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CSF biogenic amines
|
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DHPR deficiency (biopterin deficiency)
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CSF neurotransmitters & biopterin loading test
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Dopamine transporter deficiency syndrome
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CSF neurotransmitters
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GTPCH1-deficient dopa-responsive dystonia
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CSF neurotransmitters & biopterin/Phe loading test; clinical trial of L-dopamine, GTCPH gene analysis
|
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PTPS deficiency (biopterin deficiency)
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CSF neurotransmitters & biopterin loading test
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Sepiapterin reductase deficiency
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CSF neurotransmitters & biopterin/Phe loading test
|
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Tyrosine hydroxylase deficiency
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CSF neurotransmitters & TH gene analysis
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Vesicular monoamine transporter 2 (VMAT2)
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CSF monoamine metabolites
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Urea cycle
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Carbamoyl phosphate synthetase (CPS) deficiency
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CPS gene analysis
|
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N-acetyl-glutamate synthetase deficiency
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NAGS gene analysis
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Vitamins/Co-factors
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Biotinidase deficiency
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Biotinidase enzyme activity
|
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Biotin-thiamine-responsive basal ganglia disease
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SLC19A3 gene analysis
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Cerebral folate deficiency syndrome
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CSF tetrahydrofolate
|
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Hypermanganesemia with dystonia, polycythemia, and cirrhosis
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Whole-blood manganese concentrations, SLC30A10 gene analysis
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Pyridoxamine 5’-phosphate oxidase deficiency
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Plasma, CSF
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