Alanine Amino Transferase (ALT)

This ALT procedure is based on principles outlined by Wroblewski and LaDue1 and utilizes a modification of the methodology recommended by the International Federation of Clinical Chemistry (IFCC). ALT transfers the amino group from alanine to α-oxoglutarate to form pyruvate and glutamate. The pyruvate enters a lactate dehydrogenase (LD) catalyzed reaction with NADH to produce lactate and NAD+. The decrease in absorbance due to the consumption of NADH is measured at 340nm and is proportional to the ALT activity in the sample
Monday - Friday
Within 24 hours
Purpose and principle: 
Alanine aminotransferase (ALT) measurements are useful in the diagnosis and treatment of certain liver diseases (e.g., viral hepatitis and cirrhosis) and heart disease. ALT is an enzyme involved in amino acid metabolism and is, therefore, found in many tissues. The highest levels of ALT are found in the liver and kidney tissues. Tissue destruction leads to the release of the intracellular enzyme into the circulating blood. Markedly elevated serum ALT levels may be found in a variety of diseases which involve the liver, such as hepatitis, mononucleosis and cirrhosis. These very high levels of ALT are not usually observed in other diseases processes (e.g. myocardial infarction); thus, ALT is regarded as a reasonably specific indicator of liver disease.
Specimen Requirements: 
Type: Peripheral blood

  • Serum, gel
  • Plasma, gel
Sample Volume: 0.5 mL
Stability (collection to shipping of the sample):
  • Refrigerated: 3 days
  • Frozen: > 3 days

Unacceptable Conditions: Moderate-to-gross hemolysis

Specimen Retention Time: 5 days
Reference Values: 
7 - 52 U/L
CPT Code (s): 

UFHPL Test #: 20025

UFHPL Epic order code: LAB132

Collection procedure: 
Serum gel tubes should be centrifuged within 2 hours of collection.
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