Liver Blood Tests
Table of Contents
- What are the basic functions of the liver?
- What are common liver blood tests?
- What are the aminotransferases?
- Normally, where are the aminotransferases?
- What are normal levels of AST and ALT?
- What do high (elevated) liver tests (AST and ALT) mean?
- Do AST and ALT test results indicate liver function?
- What blood tests are done to detect liver function?
- What blood tests are done to detect liver function? (Continued)
- What are some common reasons for abnormal liver tests?
- What medications can cause increased liver enzyme tests (abnormal aminotransferase levels)?
- What medications can cause increased liver enzyme tests (abnormal aminotransferase levels)? (continued)
- What conditions can cause very high aminotransferase levels?
- What are some of the less common causes of elevated liver blood tests?
- What are some of the less common causes of elevated liver blood tests? (continued)
- How are healthy people evaluated for mild to moderate rises in aminotransferase levels?
- How are healthy people evaluated for mild to moderate rises in aminotransferase levels? (continued)
- How about monitoring liver blood tests?
- What about the other liver enzymes?
What blood tests are done to detect liver function? (Continued)
- Platelet count: Low platelet count (thrombocytopenia) has many causes, one of which can be advanced liver disease. Normal platelet counts are about 150,000 to 400,000 per microliter (mcL).
- Glucose: Glucose level is maintained in the body by a variety of mechanisms. The liver can release glucose in the blood for nourishment of other cells in case of starvation with insufficient oral intake of glucose. This process, called gluconeogenesis, is another major function of the liver. In advanced liver disease, this function of the liver can be compromised leading to unusually low glucose levels in the absence of adequate oral intake. Conversely, a large number of people with liver cirrhosis become glucose intolerant and develop diabetes.
- GGT (Gamma-glutamyl transpeptidase): This enzyme is thought to indicate possible liver damage; the higher the abnormal level, the more likely there is liver damage. Normal levels of GGT are about 9 to 48 U/L.
- ALP (alkaline phosphatase): The liver synthesizes the highest amounts of this enzyme so high levels in the blood may suggest liver injury among other causes. Normal levels of ALP are about 45 to 115 U/L.
- LD or LDH
- (Lactate dehydrogenase): This enzyme may be elevated in many types of diseases, including liver disease. Normal levels are about 122 to 222U/L.
Note that many hospitals and doctor's offices list a liver function panel as part of a lab workup. These panels vary and may consist of AST, ALT and some or all of the tests listed above. In addition, the normal panel values may vary somewhat, especially between adult men, women and children so viewing the "normal" ranges of test values is always recommended. In addition, some clinicians recommend other tests such as serum ammonia and serum lactate levels in their panels.