Selected disorders and relevant tests

DISORDER

SAMPLE

TEST

Adrenoleucodystrophy

Plasma

Very long chain

fatty acids (VLCFA)

Anitquin deficiency (pyridoxine responsive seizures)

Urine

Piperideine-6-carboxylate (part of metabolic profile)

Arginine:glycine amidinotransferase

(AGAT)

Plasma

& Urine

Creatine and

Guanidinoacetate

Alkaptonuria

Urine

Organic acid profile –

homogentisic acid

Creatine transporter defect

(X-linked)

Urine

Creatine and

Guanidinoacetate (part of metabolic profile)

Canavan's disease

Urine

Organic acid profile –

N-acetylaspartic acid

Congenital Disorders of Glycosylation

Serum

Transferrin Isoform

analysis

Cystinosis

White cell

pellet

White cell cystine

Fatty acid oxidation

defects during an episode

or interval sample

Plasma

Acylcarnitine profile

Urine

Organic acid profile,

Acylglycines

Guanidinoacetate methyltransferase

(GAMT)

Plasma

& Urine

Creatine and

Guanidinoacetate

Gyrate atrophy

Urine

Amino acid quantitation

 - ornithine (part of metabolic profile)

Gyrate atrophy

Plasma

Amino acid quantification

- ornithine

Lesch-Nyhan syndrome

Urine

Hypoxanthine and Xanthine (part of metabolic profile)

Tyrosinaemia Type I

Urine

Organic acid profile

- succinylacetone

Homocysteinaemia

Plasma

Homocysteine, total

4-Hydroxybutyric

aciduria

Urine

Organic acid profile

-4-hydroxybutyrate

Hypophosphatasia

Urine

or Plasma

Amino acid quantification - phosphoethanolamine

Hypophosphatasia

Plasma

Alkaline phosphatase

LCHAD deficiency

Fibroblast

cell line

LCHAD specific assay

Maple Syrup Urine

Disease

Plasma

Quantitation of

branched chain

amino acids

MCAD deficiency

   

Plasma

Carnitine

Urine

Acylglycines

Methylmalonic

acidaemia

Urine

MMA Screen

Plasma

Quantification of

MMA

Molybdenum

co-factor deficiency

Serum

Uric acid

Molybdenum co-factor deficiency

Urine

or Plasma

S-Sulphocysteine

MPS disorders

Urine

DMB screen/

GAG tandem mass spectrometry

Whole

Blood

Specific enzyme assay

(Adelaide W&CH)

Nonketotic hyperglycinaemia

Plasma

& CSF

Amino acid quantification

 - glycine

Ornithine carbamoyltransferase (OTC) hemizygote

Urine

Orotic acid

(part of metabolic profile)

Plasma

Amino acid quantification

 - glutamine & citrulline

Peroxisomal disorders including Zellweger syndrome

Plasma

Very long chain

fatty acids (VLCFA)

Succinate semialdehyde dehydrogenase deficiency

Urine

Organic acid profile

-4-hydroxybutyrate

Smith-Lemli-Opitz (SLO) syndrome

Plasma

7-Dehydrocholesterol

(7DHC)

Urea cycle disorders

Plasma

Amino acid quantitation

and ammonia

Urine

Amino acid and

organic acid profile