SGPT, also known as ALT (Alanine Aminotransferase), is a common enzyme tested in routine blood work, particularly when assessing liver health. This article will explain what SGPT/ALT is, how to interpret your test results, common reasons for elevated levels, and the appropriate steps to take if your levels are abnormal.
Understanding SGPT/ALT
SGPT (Serum Glutamic Pyruvic Transaminase) and ALT (Alanine Aminotransferase) refer to the same enzyme. This enzyme plays a role in metabolism, specifically by converting alanine to pyruvate, a process involved in energy production. While found in small amounts in other tissues like the kidneys and heart, ALT is most abundant within liver cells.
The presence of ALT in the bloodstream indicates that liver cells have been damaged or are dying. When liver cells are injured or inflamed, they release this enzyme into the blood, leading to elevated levels. A higher concentration of ALT suggests potential liver issues.
Interpreting Your Results
SGPT/ALT blood test results are expressed in units per liter (U/L). The normal reference range for SGPT/ALT falls between 7 to 56 U/L, though this can vary depending on the laboratory.
Elevated levels indicate liver injury or inflammation. A mild increase, between 56 and 100 U/L, suggests liver stress or early issues like fatty liver disease or medication side effects. Significantly higher levels, particularly those above 100 U/L, indicate more substantial liver damage or conditions such as hepatitis. Low SGPT/ALT levels are not a cause for concern.
Common Causes of Elevated Levels
Several conditions and factors can lead to elevated SGPT/ALT levels. Non-alcoholic fatty liver disease (NAFLD) is a frequent cause, often linked to obesity and poor diet, where fat accumulates in the liver. Alcoholic liver disease, resulting from heavy alcohol consumption, can also significantly raise these enzyme levels due to the liver’s efforts to process alcohol.
Viral hepatitis, including types A, B, and C, causes inflammation of the liver, leading to the release of ALT into the bloodstream. Certain medications, such as acetaminophen, statins, and some antibiotics, can induce liver injury and consequently elevate ALT levels. Autoimmune hepatitis, a condition where the body’s immune system attacks liver cells, is another potential cause.
Less common causes include hemochromatosis, an inherited condition causing iron overload in the liver, and Wilson’s disease, which leads to copper accumulation. Muscle injury or strenuous physical activity can also temporarily elevate ALT levels, as the enzyme is present in muscle tissue. While a high ALT level warrants investigation, it does not automatically indicate severe liver disease.
Next Steps After an Abnormal Result
If your SGPT/ALT results are abnormal, consulting a healthcare professional is important for proper diagnosis and management. Your doctor will consider your medical history, symptoms, and other lab tests to determine the underlying cause. Further tests, such as additional liver function tests, imaging studies like an ultrasound, or viral markers for hepatitis, may be recommended.
Lifestyle adjustments are part of the management plan, particularly for mild elevations. These may include dietary changes, regular exercise, weight management, and avoiding alcohol, all under medical supervision. Avoid self-diagnosis or making significant changes to your medication regimen without consulting your doctor.