Definition

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.

Alternative Names

5'-NT

How the Test is Performed

Blood is drawn from a vein. You may feel slight pain or a sting when the needle is inserted. Afterward, there may be some throbbing.

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:

• Acetaminophen (Tylenol)
• Halothane
• Isoniazid
• Methyldopa
• Nitrofurantoin

Why the Test is Performed

Your provider 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.

Normal Results

The normal value is 2 to 17 units per liter.

Normal value ranges may vary slightly among different laboratories. Talk to your provider 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:

• Cirrhosis (scarring of the liver and poor liver function)
• Flow of bile from the liver is blocked (cholestasis)
• Heart failure
• Hepatitis (inflamed liver)
• Liver cancer or tumor
• Liver ischemia (reduced blood flow to the liver)
• Liver necrosis (death of liver tissue)
• Lung disease
• Ovarian cancer
• Pancreas disease
• Rheumatoid arthritis
• Use of medicines that are toxic to the liver

Risks

Slight risks from having blood drawn may include:

• Excessive bleeding
• Fainting or feeling lightheaded
• Hematoma (blood accumulating under the skin)
• Infection (a slight risk any time the skin is broken)
• Bruising

References

Pincus MR, Carty RP. Clinical enzymology. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 21.

Pratt DS. Liver chemistry and function tests. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 73.