Doctors diagnose hepatitis based on a physical examination and the results of blood tests.
In addition to specific tests for hepatitis antibodies, doctors will order other types of blood tests to evaluate liver function.
In people suspected of having or carrying viral hepatitis, doctors will measure certain substances in the blood.
Topics covered in this snack-sized chapter:
- Bilirubin is one of the most important factors indicative of hepatitis
- It is a red-yellow pigment that is normally metabolized in the liver and then excreted in the urine
Liver Enzymes (Aminotransferases):
- In patients with hepatitis, the liver cannot process bilirubin, and blood levels of this substance rise
- Enzymes known as aminotransferases, including aspartate (AST) and alanine (ALT), are released when the liver is damaged
- Measurements of these enzymes, particularly ALT, are the least expensive and most noninvasive tests for determining severity of the underlying liver disease and monitoring treatment effectiveness
Alkaline Phosphatase (ALP):
- Enzyme levels vary, however, and are not always an accurate indicator of disease activity
Serum Albumin Concentration:
- High ALP levels can indicate bile duct blockage
Prothrombin Time (PT):
- Serum albumin measures protein in the blood (low levels indicate poor liver function)
The liver tissue sample is taken in a process called a liver biopsy.
Patient will either be sedated or given a local anesthetic, and a tiny sample of liver tissue will be removed with a long needle through a small incision on your right side.
If patient have chronic hepatitis B and C, a biopsy can determine the stage and severity of disease.
A liver biopsy can also be used to diagnose some of the complications of advanced hepatitis including fibrosis, cirrhosis, and liver cancer.
A liver biopsy is not without risk. Dangerous bleeding can sometimes occur, as well as infection.
There is now a trend to use less invasive methods of diagnosing liver tissue damage from chronic hepatitis.
Other tests for advanced disease include checking your liver for signs of fibrosis (stiffening from scarring), which can tell your doctor how far along your hepatitis has progressed.
- The PT test measures in seconds the time it takes for blood clots to form
Fluid from your abdomen can be tested to help differentiate among the many possible causes of liver disease.
During this test, a doctor will remove the fluid through a needle.
This non-invasive test is a means of checking for fibrosis and uses sound waves to measure the liver’s stiffness.
Elastography tests are most accurate in identifying advanced disease.
These are panels of blood tests that look for abnormal levels of certain substances in the blood (surrogate markers) that seem to parallel the development of fibrosis and cirrhosis.
These markers are different than the usual blood tests done to diagnose hepatitis.