5'-nucleotidase (5'-NT) is a protein produced by the liver. A test can be done to measure the amount of this protein in your blood.
How the Test is Performed
Blood is drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.
Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm.
Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.
In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects into a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.
How to Prepare for the Test
Your health care provider may tell you to stop taking some medicines that could interfere with the test. Drugs that may affect results include:
How the Test will Feel
You may feel slight pain or a sting when the needle is inserted. Afterward, there may be some throbbing.
Why the Test is Performed
Your doctor may order this test if you have signs of a liver problem. It is used mostly to tell if the high protein level is due to liver damage or skeletal muscle damage.
The normal value is 2 to 17 units per liter.
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.
What Abnormal Results Mean
Greater than normal levels may indicate:
Cholestasis (when bile, which is made by the liver to help digest fats, is blocked from flowing out of the liver
Veins and arteries vary in size so it may be harder to get a blood sample from one person than another. Other slight from having blood drawn may include:
Fainting or feeling light-headed
Hematoma (blood accumulating under the skin)
Infection (a slight risk any time the skin is broken)
Pratt DS. Liver chemistry and function tests. In: In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger & Fordtran’s Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2010:chap 73.
Paula J. Busse, MD, Assistant Professor of Medicine, Division of Clinical Immunology, Mount Sinai School of Medicine, New York, NY, Review provided by VeriMed Healthcare Network. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.