Alanine Transaminase (ALT, SGPT)

Alanine Transaminase (ALT)

Alanine Transaminase (ALT), also known as serum glutamate-pyruvate transaminase (SGPT), is an enzyme primarily found in the liver. The ALT test measures the level of this enzyme in the blood and is used to evaluate liver health and detect liver damage or disease.

1. What Is ALT?

• ALT is an enzyme that helps convert alanine (an amino acid) into energy for liver cells.

• It is found mainly in the liver, with smaller amounts in the kidneys, heart, and muscles.

• When liver cells are damaged, ALT leaks into the bloodstream, making it a useful marker for liver injury.

2. Why Is the ALT Test Performed?

The ALT test is used to:

• Detect liver damage from conditions like hepatitis, fatty liver disease, or alcohol abuse.

• Monitor the effects of medications or treatments that may harm the liver.

• Evaluate unexplained symptoms such as jaundice, fatigue, or abdominal pain.

• Track liver function in people with chronic liver disease.

3. ALT Reference Ranges

• Normal range: 7 – 56 units per liter (U/L)

• Slight variations may exist depending on the lab and patient characteristics.

4. How to Interpret ALT Results

🔹 Mildly Elevated ALT:

• May be caused by fatty liver disease, alcohol use, or certain medications (e.g., statins, acetaminophen).

🔹 Moderately to Severely Elevated ALT:

• Suggests more significant liver injury, often from viral hepatitis, toxins, or liver inflammation.

• ALT levels greater than 10x normal often indicate acute hepatitis or liver damage.

5. What Can Affect ALT Levels?

• Viral infections (e.g., hepatitis A, B, C)

• Alcohol consumption

• Non-alcoholic fatty liver disease (NAFLD)

• Autoimmune liver diseases

• Medications or supplements toxic to the liver

• Strenuous exercise (can temporarily raise ALT)

6. How to Maintain Healthy ALT Levels

• Maintain a healthy weight and follow a balanced diet

• Avoid excessive alcohol consumption

• Use medications only as directed and avoid unnecessary over-the-counter drugs

• Get vaccinated for hepatitis A and B if at risk

• Exercise regularly and manage underlying conditions like diabetes or high cholesterol

7. When to See a Doctor

🚨 Contact your healthcare provider if you:

• Have ALT levels above the normal range

• Experience symptoms of liver disease such as jaundice, dark urine, or upper right abdominal pain

• Are taking medications known to affect the liver

🔹 Key Takeaways

✅ ALT is a liver enzyme used to detect liver inflammation or damage.

✅ Elevated ALT levels may indicate liver disease, infections, or medication effects.

✅ Managing risk factors and lifestyle can help maintain normal ALT levels and liver health.