An SGPT, or ALT, blood test measures the amount of alanine transaminase in the blood, which is a plentiful enzyme in the liver, explains MedlinePlus. Because liver injury releases this enzyme into the blood, an SGPT test is usually performed to diagnose liver problems.
A normal SGPT result typically ranges from 10 to 40 international units per liter, according to MedlinePlus. Elevated SGPT levels may indicate cirrhosis, hepatitis, pancreatitis, mononucleosis, a benign liver tumor or cancer. Taking medications that are toxic to the liver or having a problem with blood flow to the liver may also cause SGPT levels to increase.