1 mL blood in a HEPARIN or EDTA tube. If collecting White Cell Enzymes as well then collect all blood into EDTA tubes.
Preference is EDTA tube, Heparin and Micro-Heparin all accepted
Fasting sample is recommended.
For infants, pre-feeding sample is preferred
The reference interval will be provided with the result.
UOM: 16%
Very Long Chain Fatty Acids is the screening test for peroxisomal disorders, in particular the peroxisomal biogenesis disorders (e.g. Zellwegers syndrome) and X-linked adrenoleukodystrophy. The former usually presents in infancy and is associated with dysmorphism, hypotonia, seizures and mental retardation.
ALD is a common cause of Addison's in males. It can also result in a progressive leukodystrophy in boys and a myeloneuropathy in men. Female carriers can have variable spinal cord symptoms.
See X-Linked Adrenoleukodystrophy - Molecular Genetics
VLCFA's are normal in the peroxisomal conditions Refsums disease and Rhizomelic chondrodysplastic punctata. Serum phytanic acid and red cell plasmalogens can be used to diagnose these conditions respectively.
Phytanic acid and Pristanic acid are now routinely analysed along with VLCFA on all samples.
For further information contact the laboratory (ex 22016 or via lablink) or, contact the metabolic physician on-call 09 367 0000
If collecting White Cell Enzymes too, do not separate plasma, leave all EDTA tubes at room temperature and transport as per White Cell Enzymes.
EDTA or Heparin - Separate plasma - 0.3mL minimum. Send frozen to LabPlus (-20 C)