Synonyms

   SGPT , serum glutamic-pyruvic transaminase

Clinical Significance

   ALT test measures the amount of ALT in the blood. High levels of ALT in the blood can indicate a liver problem. ALT blood test may be helpful in early detection of liver disease.

Specimen

   Serum or plasma

Stability

   3 days at 20 - 25 C

   7 days at 4 to 8 C

   7 days at -20 C

Reference Range

   Male - up to 41 U/L

   Female - up to 33 U/L

Interpretation

   Slightly high ALT levels may be caused by:

       Alcohol abuse,

       Cirrhosis (long-term damage and scarring of the liver),

       Mononucleosis,

       Drugs such as statins, aspirin, and some sleep aids

   Moderately high ALT levels may be because of:

       Chronic (ongoing) liver disease,

       Alcohol abuse,

       Cirrhosis,

       Blockage of the bile ducts,

       Heart attack or heart failure (when your heart can’t pump enough blood to your body),

       Kidney damage,

       Muscle injury,

       Damage to red blood cells,

       Heat stroke,

       Too much vitamin A.

   Very high ALT levels can be caused by:

       Acute viral hepatitis,

       An overdose of drugs such as acetaminophen (Tylenol),

       Liver cancer,

       Sepsis.

Limitation

   ALT can be elevated without any underlying health problem. Multiple factors can affect ALT, and in most cases, high ALT is not a sign of severe liver disease.

   Some individual factors that can influence normal level of ALT, are

       Exercise: Intense or extreme exercise can cause a temporary boost in ALT levels.

       Medications: A number of medications and supplements can alter ALT measurements.

       Sex: Males typically have higher levels of ALT, which is believed to be related to hormonal differences.

       Menstruation: ALT levels can go up or down during the course of the menstrual cycle.

       Age: There is a tendency for ALT levels to decrease with older age, although the exact reason for this is not known.

       Body mass index: Several research studies have found an association between ALT levels and body mass index, which may change the interpretation of test results in people with obesity.