Liver Function Test (LFT) levels for hepatitis can vary, but they are often significantly elevated, especially during active infection. Specifically, very high levels, over 1,000 units per liter (U/L), are frequently seen with viral hepatitis. It's important to note that not all elevated LFTs indicate hepatitis, as other conditions can also cause increases.
Understanding LFTs and Hepatitis
LFTs are a group of blood tests that assess liver health. They measure enzymes and proteins produced by the liver, such as:
- Alanine transaminase (ALT): A liver enzyme that is released when liver cells are damaged. Elevated ALT levels are a common indicator of liver injury.
- Aspartate transaminase (AST): Another liver enzyme that, similar to ALT, is released when liver cells are damaged.
LFT Levels in Hepatitis: What to Expect
In cases of hepatitis, especially viral hepatitis, you'll likely see significant elevations in these liver enzymes:
| LFT Component | Normal Ranges | Levels in Hepatitis |
|---|---|---|
| ALT | Generally below 25 IU/L in females, below 33 IU/L in males | Often very high, >1,000 U/L in acute viral hepatitis |
| AST | Varies, usually slightly less than ALT in healthy individuals | Elevated, though may not be as high as ALT in some types of hepatitis |
Key Takeaways
- Very high LFT levels (above 1,000 U/L) are strongly suggestive of hepatitis, especially viral hepatitis.
- ALT is generally more specific for liver injury than AST.
- An ALT above 25 IU/L in females and 33 IU/L in males typically requires further evaluation to determine the cause.
Example
For instance, an individual presenting with jaundice (yellowing of the skin and eyes) and fatigue who has an ALT level of 1,500 U/L would be highly suspected of having viral hepatitis.
Important Considerations
- These levels should always be interpreted by a healthcare professional in the context of an individual's complete medical history, physical examination, and other diagnostic tests.
- Other causes of elevated LFTs include drug-induced liver injury, ischemic hepatitis (liver damage due to lack of blood flow), and other non-hepatic conditions.
