Types of Hepatitis
- Hepatitis A: Hepatitis A is caused by the hepatitis A virus (HAV). This type of hepatitis is spread easily through contact with stool or blood of an infected person. This can occur through contaminated water and food, sexual contact, or shared intravenous needles. The hepatitis A virus causes acute infections that are often mild, typically resolving without treatment within several weeks. Highly effective vaccines are available to prevent hepatitis A.
- Hepatitis B: Hepatitis B is caused by the hepatitis B virus (HBV). Hepatitis B can be spread through contact with an infected person’s blood or certain other body fluids, including transmission from a mother to her baby. This virus can cause either acute or chronic infections. Highly effective hepatitis B vaccination is available to prevent infection.
- Hepatitis C: Hepatitis C is caused by the hepatitis C virus (HCV). The hepatitis C virus is spread through exposure to the blood of a person with this infection, often through the use of injectable drugs and during birth to a mother with an HCV infection. This virus can cause both acute and chronic infections. Currently, there is no vaccine to prevent hepatitis C; however, it is treatable.
- Hepatitis D: Also known as delta hepatitis, hepatitis D is caused by the hepatitis D virus (HDV). This virus is unique in that it only infects people who already have the hepatitis B virus. HDV is spread through the blood or other body fluid of an infected person, most often from sharing needles and unprotected sex with a person who has this infection. Hepatitis D can be either acute or chronic. The vaccine for hepatitis B can prevent hepatitis D because only those infected with hepatitis B can contract HDV.
- Hepatitis E: Hepatitis E is caused by the hepatitis E virus (HEV). Hepatitis E is spread through ingesting small amounts of the virus, often through drinking contaminated water and from animals to people when consuming undercooked foods like pork or wild game. HEV causes an acute infection that doesn’t require treatment.
Less commonly, hepatitis can be caused by other types of infections, including those caused by cytomegalovirus, Epstein-Barr virus, and the herpes simplex virus.
There are many conditions that can cause noninfectious hepatitis, including:
- Alcoholic hepatitis: Alcoholic hepatitis is caused by long-term and heavy alcohol use. The majority of patients diagnosed with alcoholic hepatitis have a history of heavy alcohol use for two or more decades.
- Toxic hepatitis: The liver breaks down many substances for the body to use and/or eliminate. Prescription drugs, over-the-counter drugs, and herbal supplements taken in doses higher than recommended can cause hepatitis, while other drugs can damage the liver even when taken in small doses. Drugs that may cause toxic hepatitis when used incorrectly include anabolic steroids, birth control pills, statins, nonsteroidal anti-inflammatory drugs, and medications containing acetaminophen.
- Autoimmune hepatitis: Autoimmune hepatitis is a chronic form of hepatitis in which a person’s immune system mistakenly attacks healthy cells in the liver. The cause of this form of hepatitis is not fully understood, but researchers believe that genetics and a person’s environment likely play a role. Rarely, a hepatitis A infection can trigger the development of autoimmune hepatitis.
The Role of Hepatitis Tests
The purpose of hepatitis tests is to screen for and diagnose hepatitis, evaluate the liver, and to determine the underlying cause of hepatitis:
- Screening for viral hepatitis infection: Screening involves testing to look for diseases before a person develops symptoms. Hepatitis tests are commonly used to screen for two types of viral hepatitis, hepatitis B and hepatitis C, in certain populations.
- Diagnose the underlying cause of hepatitis: Hepatitis testing is often used to determine the underlying cause of inflammation in the liver or liver damage. Testing can identify whether a person has a viral hepatitis infection, if hepatitis is acute or chronic, and whether they are contagious and can spread viral hepatitis to others.
- Assessing immunity to viral hepatitis: After a patient recovers from certain types of viral hepatitis, including hepatitis A and hepatitis B, their body develops protective antibodies, and they become immune to future infections. Hepatitis testing can help doctors understand if a patient has developed immunity based on a past infection or successful vaccination.
- Guiding treatment for hepatitis: Hepatitis testing may be ordered to help determine the most appropriate treatment for hepatitis. Testing can also help detect complications of hepatitis and assess a patient’s response to treatment.
Who should get testing?
Screening tests for hepatitis B and C attempt to find these infections early, before symptoms develop and when they’re easier to treat. Screening for viral hepatitis helps to reduce damage to the liver and prevent patients from knowingly spreading hepatitis to others. A patient’s doctor can help determine the need for screening tests, as recommendations vary based on a patient’s age, sex, family history, and other risk factors. Screening recommendations include:
- Screening for hepatitis B: Hepatitis B screening is recommended for people at an increased risk of contracting HBV. Groups that may benefit from screening include pregnant people, people born in parts of the world where hepatitis B is more common, people who didn’t receive a hepatitis B vaccine as an infant, HIV-positive people, users of injectable drugs, and people at risk of HBV infection due to certain sexual practices.
- Screening for hepatitis C: All adults over age 18 should be screened for hepatitis C at least once, except in areas with very low prevalence of HCV. Screening is also recommended during each pregnancy and periodically for patients with risk factors for HCV infection. Risk factors for HCV include current or past injectable drug use, having a blood transfusion or organ transplant before July 1992, being on kidney dialysis, having contact with needles at work, working or living in a prison, being born to a mother with hepatitis C, having an HIV infection, and engaging in certain sexual practices.
Hepatitis testing may also be recommended for patients who have symptoms of liver damage or abnormal liver function tests. Many patients experience few or no symptoms of acute hepatitis. When symptoms do occur, they may include:
- Yellowing of the skin and eyes, called jaundice
- Loss of appetite
- Dark-colored urine
- Pale-colored stool
- Nausea and vomiting
Symptoms of chronic and non-infectious hepatitis can be wide ranging, involving almost any body system. Symptoms may include:
- Feeling uncomfortable and unwell
- Weight loss
- Low-grade fever
- Discomfort in the upper abdomen
- Absence of menstruation
Getting test results
There are many tests used to screen for, diagnose, and evaluate hepatitis. Multiple tests are often necessary to understand a patient’s condition.
How long it takes to receive test results depends on the test(s) performed and whether test samples must be sent to a specialized laboratory for analysis. Although some test results may be available rather quickly, other tests may take several days or weeks.
Results of hepatitis tests may be shared with a patient during a follow-up appointment, phone call, or through an online medical chart. Patients with questions about when to expect test results or what results mean for their health should talk to their doctor for more information.
Types of Hepatitis Tests
Hepatitis testing often begins with preliminary tests to evaluate the liver and detect evidence of hepatitis. Depending on the patient’s symptoms, medical history, and the results of a physical exam, a patient’s doctor may order individual tests or broad test panels such as a comprehensive metabolic panel and a liver panel. These tests may be used to evaluate the liver, detect evidence of hepatitis, and begin to narrow down the underlying cause of a patient’s condition.
Tests used to diagnose, evaluate, and guide treatment for viral hepatitis may be performed individually when a person has a known or suspected exposure to a specific type of viral hepatitis. In patients without a known or expected exposure, tests may be performed together as part of an acute viral hepatitis panel. An acute viral hepatitis panel detects evidence of the three most common types of hepatitis in the United States: hepatitis A, B, and C.
Viral hepatitis testing detects antibodies, antigens, or the genetic material of a hepatitis virus. Antigens are substances from the virus that produce an immune response, while antibodies are produced by the immune system after an infection. Tests related to viral hepatitis include:
|Tests Related to Viral Hepatitis|
|Test Name||Test Sample||What It Measures|
|Hepatitis A Testing||Blood||HAV antibodies|
|Hepatitis B Testing||Blood||Antibodies, antigens, and genetic material of HBV|
|Hepatitis C Testing||Blood||Antibodies and genetic material of HCV|
|Hepatitis D Tests||Blood||Antibodies and genetic material of HDV|
|Hepatitis E Tests||Blood||Antibodies and genetic material of HEV|
If a non-infectious cause of hepatitis is suspected, a doctor may recommend other tests. Tests related to non-infectious hepatitis include:
|Tests Related to Noninfectious Hepatitis|
|Test Name||Test Sample||What It Measures|
|Antinuclear Antibody (ANA)||Blood||Antibodies present in several autoimmune disorders|
|Smooth Muscle Antibody (SMA)||Blood||Antibodies present in autoimmune hepatitis|
|Anti-LKM-1 Antibody||Blood||Antibodies present in autoimmune hepatitis|
|Antimitochondrial Antibody (AMA)||Blood||Antibodies present in primary biliary cholangitis, a type of liver disease|
Additional tests involved in diagnosing hepatitis and evaluating liver damage include a liver biopsy and imaging tests. A liver biopsy involves using a needle to remove a small amount of liver tissue to examine under a microscope for evidence of liver damage or disease. Imaging tests that may be used include ultrasounds, CT scans, MRIs, or x-rays.
Getting Tested for Hepatitis
Hepatitis testing is typically ordered by a doctor in order to screen patients for hepatitis, to evaluate liver damage, or when there are signs or symptoms consistent with hepatitis. Many hepatitis tests require a blood sample, which can be drawn in a doctor’s office or other medical setting.
At-home hepatitis tests are available to test for hepatitis B and C in the blood. These tests involve collecting a blood sample by pricking a finger and sending the sample to a laboratory for analysis. Some at-home test kits look for only one of these type of viral hepatitis, while others test for both types in the same blood sample:
- At-home hepatitis B testing: At-home hepatitis B testing detects hepatitis B surface antigen.
- At-home hepatitis C testing: At-home hepatitis C testing tests for hepatitis C antibodies.
Because diagnosing, evaluating, and monitoring hepatitis can involve a variety of tests, at-home hepatitis testing is not a substitute for care provided by a doctor or specialist. Patients with questions about the use of at-home hepatitis tests should talk to their doctor.