Skip navigation | ||
|
||
Medical Encyclopedia |
|
Other encyclopedia topics: | A-Ag Ah-Ap Aq-Az B-Bk Bl-Bz C-Cg Ch-Co Cp-Cz D-Di Dj-Dz E-Ep Eq-Ez F G H-Hf Hg-Hz I-In Io-Iz J K L-Ln Lo-Lz M-Mf Mg-Mz N O P-Pl Pm-Pz Q R S-Sh Si-Sp Sq-Sz T-Tn To-Tz U V W X Y Z 0-9 |
Contents of this page: | |
|
Alternative names Return to top
ApoB100; Apoprotein B100Definition Return to top
This test measures the amount of apolipoprotein B100 (apoB100) in the blood.
Lipoproteins are large complexes of molecules that transport lipids (primarily triglycerides and cholesterols) through the blood. Apolipoproteins are proteins on the surface of the lipoprotein complex that bind to specific enzymes or transport proteins on the cell membranes; this directs the lipoprotein to the proper site of metabolism. ApoB100 is in an intermediate form of lipoprotein (IDL) and an low density lipoprotein (LDL).
How the test is performed Return to top
Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic, and a tourniquet (an elastic band) or blood pressure cuff is placed around the upper arm to apply pressure and cause veins below the tourniquet to distend (fill with blood).
A needle is inserted into the vein, and the blood is collected in an airtight vial or a syringe. During the procedure, the tourniquet is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.
Infant or young child:
The area is cleansed with antiseptic and punctured with a sharp needle or a lancet. The blood may be collected in a pipette (small glass tube), on a slide, onto a test strip, or into a small container. Cotton or a bandage may be applied to the puncture site if there is any continued bleeding.
How to prepare for the test Return to top
Fasting for 4 to 6 hours may be recommended.How the test will feel Return to top
When the needle is inserted to draw blood, some people may feel moderate pain, while others may feel only a prick or stinging sensation. Afterward, there may be some throbbing.Why the test is performed Return to top
Most often, this test is performed to help determine the cause of hyperlipidemia (elevated blood lipid levels).
ApoB100 is a form of apoB that occurs in LDL and IDL but not in chylomicrons (large lipoprotein particles that contain apoB48 and other apolipoproteins).
Normal Values Return to top
The normal range is 40 to 125 mg/dL.What abnormal results mean Return to top
Elevated levels of apoB occur in familial combined hyperlipidemia and acquired hyperlipidemia (elevated blood lipid levels). ApoB100 measurements can help to determine the specific type or cause of hyperlipidemia.
Other disorders that may be associated with elevated apoB levels include angina pectoris and heart attack.
What the risks are Return to top
Special considerations Return to top
Apolipoprotein levels can be measured directly, unlike HDL and LDL measurements, which are indirect. This test may give a much more accurate picture of your health, including your risk for heart disease.
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than others.
Update Date: 5/20/2003 Updated by: Bridget Martell, M.D., Department of Internal Medicine, Albert Einstein College of Medicine, New York, NY. Review provided by VeriMed Healthcare Network.
Home | Health Topics | Drug Information | Encyclopedia | Dictionary | News | Directories | Other Resources | |
Copyright | Privacy | Accessibility | Selection Guidelines U.S. National Library of Medicine, 8600 Rockville Pike, Bethesda, MD 20894 National Institutes of Health | Department of Health & Human Services |
Page last updated: 28 October 2004 |