Hepatitis

What is it?
Tests
Treatments
Sources

Tests
Acute hepatitis is often suspected because of symptoms (fever, loss of appetite, nausea), often accompanied by dark urine, pale stools, and yellow discoloration of the skin and the whites of the eyes (termed jaundice or icterus). Chronic hepatitis is more commonly detected as a result of abnormal laboratory tests. In some cases, testing for exposure to hepatitis B or hepatitis C is done because of risky behavior (use of illegal drugs, multiple sex partners) or at the time of blood donation.

Hepatitis (especially chronic hepatitis) may be first discovered during routine testing as abnormal findings on, for example, a Comprehensive Metabolic Panel (CMP). The CMP is a group of tests frequently ordered as part of a yearly physical. It includes several tests from the liver panel. In a patient who is having no, few, or vague symptoms, these tests may be the first indication of liver inflammation or injury. The tests are used both to detect liver injury and to give an indication of how severe it may be. They include:

Alanine aminotransferase (ALT) – an enzyme found mainly in the liver; the best test for detecting hepatitis

Alkaline phosphatase (ALP) – an enzyme related to the bile ducts; often increased when they are blocked

Aspartate aminotransferase (AST) – an enzyme found in the liver and a few other places, particularly the heart and other muscles

Bilirubin, a waste product made from old blood cells; it is a yellow compound that causes jaundice and dark urine when present in increased amounts

Albumin - measures the main protein made by the liver and tells how well the liver is making this protein

Total Protein - measures albumin and all other proteins in blood, including antibodies made to help fight off infections

Other tests may be ordered when specific types of hepatitis are suspected and/or the doctor wants to rule them out. They include:

Viral testing. There are a variety of antibody and antigen tests specific for hepatitis A, B, and C (see Viral Hepatitis Table).

Inherited hepatitis may be suspected if there is a family history of liver disease. Common tests to look for the presence of inherited liver diseases include serum iron, total iron binding capacity, and ferritin for hemochromatosis and alpha-1-antitrypsin level, for alpha-1-antitrypsin deficiency. Ceruloplasmin and copper tests can help diagnose Wilson’s disease. The body normally eliminates excess copper into the bile but also binds some to an enzyme called ceruloplasmin. With Wilson’s disease, the binding and excretion processes do not work properly, resulting in decreased concentrations of ceruloplasmin in the blood but increased concentrations of free copper in the blood, urine, and liver.

Drug, alcohol, and chemical hepatitis are not usually directly tested for with a blood test. The diagnosis is arrived at by examining the patient, questioning about previous intake of chemicals, drugs, alcohol, and, where applicable, evaluating hazards the patient may have been exposed to in the workplace, such as industrial solvents.

Autoimmune hepatitis. A variety of autoantibodies may be ordered, including antinuclear antibody (ANA), both to help detect autoimmune hepatitis and to look for other associated autoimmune disorders.

Protime (PT). This test may be ordered in a person with hepatitis or suspected hepatitis; the proteins making a blood clot are mostly produced by the liver, and prolonged PT helps to indicate the severity of liver damage.

A liver biopsy, in which a needle is inserted into the liver to withdraw a small amount of cells that are examined under a microscope by a pathologist, is the most definitive way to diagnose the disease. Since this is an invasive procedure, it is used primarily when other tests are inconclusive or to determine how much damage to the liver has occurred.