Hepatitis C Screening: Who Should Be Tested and What the Blood Test Shows

What it involves

MedlinePlus describes hepatitis C as a viral disease that leads to swelling of the liver. It is caused by the hepatitis C virus, passed on when the blood of an infected person enters another person's body, and MedlinePlus says many people recently infected have no symptoms at all.

Who this is for

• Adults who have never been tested for hepatitis C and are not sure whether they ever should be
• Patients who received a blood transfusion or organ transplant, or had long-term kidney dialysis, years ago
• Patients who have ever shared a needle, or who work in a job with regular contact with blood
• Patients whose liver blood tests came back abnormal and who want to know why

What to expect

• A private conversation about your history, with no judgment, so your provider can decide what testing makes sense
• A blood draw for the antibody test, the first step MedlinePlus describes for finding the virus
• A follow-up test to confirm the result if the antibody test is positive
• A plan for the next steps, including liver checks and referral for treatment if the infection is confirmed

Why a symptom check is not enough

MedlinePlus says that most people recently infected with the virus have no symptoms, and that chronic infection often causes none either. Some people notice yellowing of the skin, and tiredness, belly pain and low mood can occur, but MedlinePlus notes that people with long-term infection often feel nothing until the liver becomes scarred, a condition called cirrhosis. That gap between infection and symptoms is the entire reason screening exists. Waiting to feel unwell means waiting until damage has already been done.

Who MedlinePlus says should be tested

MedlinePlus states that all adults ages 18 to 79 should get a one-time test for the virus. It also names the groups who are at higher risk, which makes the conversation more urgent for them: anyone who has injected street drugs or shared a needle, people on long-term kidney dialysis, health care workers with regular contact with blood, and people who received an organ transplant or a transfusion before blood screening began in 1992. People born to a mother who had the virus are on the list too, as are a few less common routes, such as sharing razors or toothbrushes.

How the test works

The first test looks for antibodies against the virus in a blood sample. MedlinePlus explains that if the antibody result is positive, a second test called a PCR confirms whether the virus is actually present, measures how much is there, and identifies its type. There are six types, called genotypes, and MedlinePlus says knowing the type helps a provider choose the best treatment. The visit itself is a short blood draw, the same kind of routine sample described in the liver function tests guide.

What a positive result does and does not mean

A positive antibody test is a reason for the confirmation test, not a final verdict. MedlinePlus says that most people, between 75 and 85 percent, who are infected go on to chronic infection unless they are treated, which carries a risk of cirrhosis and liver cancer. That sounds frightening, but the same source stresses that the outlook has changed because of newer medicines. It also says the virus is not spread by casual contact such as holding hands, kissing, coughing, sneezing, or sharing eating utensils and drinking glasses, so a diagnosis does not mean staying away from family.

Checking the liver itself

If the infection is confirmed, MedlinePlus lists tests used to find and track liver damage, including an albumin level, liver function tests, a clotting test called prothrombin time, a liver biopsy, and imaging methods that measure liver stiffness. A primary care provider orders the blood-based pieces and refers for the rest when they are needed. Many of the same liver markers also show up in a routine panel, which is how some patients first learn something is off. The fatty liver guide covers a more common reason for abnormal liver numbers.

Treatment is a conversation, not a crisis

MedlinePlus says the goal of treatment is to clear the virus from the body, which can prevent liver damage that may lead to liver failure or liver cancer. It describes newer antiviral medicines taken by mouth for 8 to 24 weeks, with an excellent cure rate and fewer side effects than older medicines, and says the choice depends on the genotype. It also advises avoiding alcohol, which can speed liver damage and reduce how well the medicines work, and checking with a provider before taking any new over-the-counter medicine or supplement. Your provider can start that discussion and arrange specialist care.

Sources

• MedlinePlus — Hepatitis C