Several blood tests can indicate Wilson's disease, although no single test is definitive. A combination of abnormal results across multiple tests raises suspicion and warrants further investigation.
Key Blood Tests for Wilson's Disease
Here's a breakdown of the key blood tests used in the diagnosis of Wilson's disease:
-
Ceruloplasmin Level:
- Typically Low: This is a hallmark finding in Wilson's disease. Ceruloplasmin is a protein that carries copper in the bloodstream. Because individuals with Wilson's disease have difficulty attaching copper to ceruloplasmin, the level of this protein is often reduced.
- Important Note: Low ceruloplasmin can also be found in other conditions, making it essential to consider other factors.
-
Serum Copper Level:
- Variable Results: Total serum copper levels can be higher, lower, or normal in Wilson's disease. This is because copper is not being properly processed and transported.
- Free Copper: More importantly, the free copper (copper not bound to ceruloplasmin) is usually elevated in Wilson's disease.
-
Liver Enzymes (ALT and AST):
- Elevated Levels: Alanine transaminase (ALT) and aspartate transaminase (AST) are liver enzymes. Elevated levels indicate liver damage, which is common in Wilson's disease.
- Non-Specific: Elevated liver enzymes are not specific to Wilson's disease and can be caused by various other liver conditions.
-
Other Blood Tests:
- Complete blood count (CBC) to assess for anemia or thrombocytopenia.
- Comprehensive metabolic panel (CMP) to assess overall liver and kidney function.
Summary of Blood Test Findings in Wilson's Disease
| Blood Test | Typical Result in Wilson's Disease |
|---|---|
| Ceruloplasmin | Low |
| Serum Copper | Variable (may be low, normal, or high) |
| Free Copper | High |
| ALT and AST | Elevated |
Important Considerations
It's vital to note that blood test results alone are not sufficient for diagnosing Wilson's disease. A doctor will consider these results in conjunction with a physical examination, patient history, and other diagnostic tests such as:
- Urine Copper Test: Measures the amount of copper excreted in the urine over 24 hours. People with Wilson's disease typically excrete more copper than normal.
- Liver Biopsy: A small sample of liver tissue is examined under a microscope to assess copper levels and liver damage.
- Genetic Testing: Identifies mutations in the ATP7B gene, which is responsible for Wilson's disease.
A definitive diagnosis requires careful evaluation by a healthcare professional specializing in liver disease or metabolic disorders.
