Leucine aminopeptidase is a type of protein called an enzyme. This enzyme is normally found in cells of the liver and small intestine.
Serum leucine aminopeptidase is a test that measures how much of the enzyme is in your blood.
Your urine can also be checked for this substance.
How the Test is Performed
A blood sample will be taken from your vein.
How to Prepare for the Test
You may need to stop taking any medicines that could change the test.
Drugs that can affect the results include estrogen and progesterone. Never stop taking any of your medicines without first talking to your doctor.
How the Test will Feel
You may feel a slight pain or sting when the needle is inserted to draw blood. There may be some throbbing at the site afterward.
Why the Test is Performed
You may need this test to check for damage to your liver. Too much leucine aminopeptidase is released into your blood when you have a liver tumor or damage to your liver cells.
This test is not done very often. Other tests, such as gamma glutamyl transpeptidase, are as accurate and easier to get.
Normal test values are:
- Male: 80 to 200 U/mL
- Female: 75 to 185 U/mL
Note: U/mL = units per milliliter
Normal value ranges may vary slightly. Some labs use different measurements or may test different specimens. Talk to your doctor about the meaning of your test results.
Veins and arteries vary in size so it may be harder to get a blood sample in one person than another.
Other slight risks from having blood drawn may include:
- Excessive bleeding
- Fainting or feeling light-headed
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
Serum leucine aminopeptidase
Berk P, Korenblat K. Approach to the patient with jaundice or abnormal liver tests. In: Goldman L, Schafer AI, eds.Cecil Medicine
Pratt DS. Liver chemistry and function tests. In: Feldman M, Friedman LS, Brandt LJ, eds.Sleisenger and Fordtran's Gastrointestinal and Liver Disease
Update Date 1/27/2013
Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang.