Clinical use
NEFA can be used for evaluation of metabolic status of people with endocrinopathies. It can be used for detection of Pheochromocytoma and of glucagon-, thyrotropin -adrenocorticotropin-secreting tumours. It is occasionally used for monitoring of control of diabetes mellitus.
Background
NEFA or free fatty acids are fundamental units in the structure of lipids in membranes and lipoproteins. NEFA are an important source of energy for the heart and for aerobically conditioned skeletal muscle. Plasma NEFA concentrations are increased in three related pathologic states that tend to cluster in individuals and that have been implicated in premature coronary artery disease: obesity, type 2 diabetes and elevated plasma triglyceride. Among other factors included in the cluster – termed the cardiovascular metabolic syndrome, insulin resistance syndrome or metabolic syndrome X – is a reduced concentration of high density lipoprotein (HDL) cholesterol, a reduction that occurs through the exchange of HDL cholesteryl ester for triglyceride in VLDL. Insulin resistance leads to impaired NEFA uptake and a rise in plasma NEFA and triglyceride concentrations. Analysis of NEFA provides information about the patients’ lipid metabolism, pathogenesis of obesity and type 2 DM, and ultimately atherosclerosis.
Reference ranges
Non – fasting: < 0.9 mM
Fasting: 0.2 – 1.8 mM
15h: 0.2 – 1.1 mM
20h: 0.6 – 1.3 mM
24h: 1.0 – 1.8 mM
Patient preparation
Spontaneous hypoglycaemia or patient may be fasted overnight
Specimen requirements
Blood specimen in a plain (red top) or Lithium Heparin (green top) tube.
Turnaround time
4 weeks
Additional Information
* Usually requested in addition to PCA sample for ‘Glucose Metabolites‘ (see separate entry) but may be requested separately.
Referred test
Referred test
Location
Paediatric Metabolic Centre