Special tests
The lipid laboratory was developed to provide special tests which are not available in routine laboratories in South Africa. This laboratory forms part of our academic teaching and research activities. Consideration will be given to setting up special investigations that can assist most cost-effectively with diagnosis and support research relevant to healthcare in South Africa.
Lipoprotein electrophoresis. Determines the nature of apoB-containing particles: LDL size, Lp(a), dysbetalipoproteinaemia, LpX, VLDL and chylomicrons. Usually done weekly.
Sterol metabolic errors. 7-dehydrocholesterol for diagnosis of Smith Lemli Opitz syndrome, can continue to test for desmosterolosis and lathosterolosis with thin layer chromatography. Done on request.
Lipase activity. Determines the capacity to remove triglyceride from blood by releasing the enzyme lipoprotein lipase from the endothelium with an injection of heparin. This test can discriminate whether enzyme or its activator is absent or an inhibitor is present. By special arrangement as it requires an injection to the patient and prompt testing.
Inherited errors. Commonly performed are genetic tests for identifying disease-causing variants in the LDL receptor, apoB, and PCSK9 all the work-up of FH. ApoE for dysbetalipoproteinaemia. Cholesterol 27-hydroxylase for cerebrotendinous xanthomatosis. Lipoprotein lipase, apoCii, apoAv for lipolytic problems. ApoCiii, endothelial lipase for high HDL cholesterol concentrations. Some investigations are done in collaboration with overseas laboratories.
Other. On occasion the lab has tested for Niemann-Pick C disease and LDL receptor activity. Certain toxicologic assays have been done that are not routinely available and are within the scope of the laboratory. The vision is to respond to clinical needs by providing the most affordable but still definitive investigation. Such investigations can be discussed with Professor Marais at 021 650 2208 or [email protected]