✓ Evidence Based

Hepatitis C Test and Diagnosis

Hepatitis C is a serious condition that can lead to chronic health problems and even death (1, 2). Therefore, it is highly recommended that everyone is tested for this virus, especially if they:

  • Have a sexual partner who is diagnosed with hepatitis C
  • Have or had a partner who had many sex partners
  • Have or had many sexual partners
  • Are a current drug user who injected drugs with needles
  • Are a former drug user who has used a needle at least once in their life
  • Have been on hemodialysis for a longer period of time due to kidney disease
  • Received an organ transplant before 1992
  • Received a blood transfusion before 1992
  • Have HIV
  • Are working in healthcare and is exposed to blood or bodily fluids
  • Have symptoms and evidence of liver disease
  • Are born between the ages of 1945 and 1965

People should be regularly tested for this condition, especially if they are in the group presented above, mostly because the beginning phase of this disease shows no symptoms at all in most cases (3). If one takes proper care and visits the doctor’s office regularly for a hepatitis C test, the doctor can see the level of liver enzymes in the blood and evaluate if they are higher than usual (4). Additionally, there are many other tests that are performed in order to set a hepatitis C diagnosis.

Summary: It’s important to get tested for the hepatitis C virus. Especially if you’ve ever been in close contact with someone who has the virus, worked in healthcare and were exposed to blood or bodily fluids, are a current or former injectable drug user, have had a blood transfusion, transplant, or hemodialysis before 1992, have HIV, or experience symptoms of liver disease.

How is Hepatitis C Diagnosed?

Hepatitis C Diagnosis

There are a few ways to diagnose a patient with hepatitis C:

1. Antibody Test

If you are wondering if you have hepatitis C, an antibody test is one way to find out (5). The first way of checking whether a patient has the infection or not is by doing a blood test for the antibody. When you opt for an antibody test, the doctors will take your blood and send it for examination at the lab (6). The test used to determine whether the blood is infected with the hepatitis C virus is called OraQuick (7). It is called this way since it gives a result in as little as 20 minutes.

The accuracy of the test is pretty high, which means that if the test does not find anything that indicates the person is infected, they are probably not (8). However, if you are doubting that you have gotten the virus in the past 6 months, you may want to do the test again later, just to be sure.

The antibody test is good, but it is definitely not perfect. In some cases, this test shows that a person has an infection, even when they do not. There are cases where patients were treated from hepatitis C before and do not currently have the virus, but the test is still positive.

Summary: The antibody test is the first way of checking whether a patient has hepatitis C. The test is called OraQuick and detects whether you have the antibody or not. It is a highly accurate test, but is not perfect. Some tests will show a person has the infection even though they do not. Or, in other cases, a previously treated patient who does not currently have the virus could show a positive result.

2. PCR Test

The next step after the positive antibody test is a PCR test (9). This test is used not only to confirm the diagnosis but to also look for the genetic material of the virus in the patient’s body (10).

In cases where the antibody test is false and the person no longer has the hepatitis C virus, the PCR test will not find anything (11). In these cases, doctors usually do the test twice to make sure.


If both the antibody and PCR tests are positive, the patient is infected with the virus and needs to start with immediate treatment.

Summary: After an antibody test, the next step is a PCR test. This test confirms the diagnosis and gathers information about the genetic material of the virus, which is important for determining treatment route. If both the antibody and PCR tests are positive, the patient is infected with the virus and will need to start treatment.

3. Liver Biopsy, Fibrosure Blood Test and Ultrasound

A liver biopsy is a test that is done prior to the start of the treatment (12). This test is used to show the severity of the virus i.e. the harm it has done to the patient’s body.

The liver biopsy is done with the help of a special needle that the doctor inserts into the liver, through the patient’s skin, with the goal of removing a sample of liver tissue (13).

This liver tissue is sent to the lab to check the damage the virus has done to the liver. Treatment is then set accordingly.

There are also other ways of measuring liver damage. These tests are a Fibrosure blood test and a test based on an ultrasound of the liver (14). The choice between damage tests depends on the patient’s condition and the doctor’s recommendation.

Summary: It is essential to determine liver damage before treatment starts. A liver biopsy is performed prior to treatment to assess this. Treatment is determined based on these results. Fibrosure blood test and even ultrasound tests can also determine liver damage. Choosing a liver damage test depends on the patient’s condition and recommendations.

4. Liver Enzyme and Function Tests

This test was formerly called the liver function test or LFT (15). We are speaking of a few blood tests that are used to detect the liver’s damage and inflammation (16). Such tests are performed after the hepatitis C diagnosis is set i.e. when the doctors are certain that the patient has the virus.

Aside from checking the damage, these tests are often used to check how well the liver is functioning. These include:

  • AST
  • ALT
  • Alkaline phosphatase
  • PT
  • Albumin
  • INR
  • Bilirubin

The doctors usually check the liver’s condition and functioning in a hepatitis C patient during the physicals or in freshly diagnosed patients. In most cases, they order a routine lab test that includes a liver test panel (17).

Most commonly, a liver enzyme and function tests are recommended to people who:

  • Drink alcohol often and excessively
  • Have a bile system disease or symptoms of it such as nausea, vomiting, abdominal pain and yellow skin
  • Are taking a medication that is bad for the liver
  • Have a liver disease

The abovementioned liver tests can be done in combinations or tested separately.

Summary: Liver enzyme function tests are important to assess liver damage and inflammation. These are tested after diagnosing to further determine a treatment plan. Liver function tests (LFT) assess AST, ALT, alkaline phosphatase, PT, albumin, INR, and bilirubin blood levels. A LFT is also recommended for patients who drink alcohol, have bile system issues, take medication bad for the liver, or have liver disease.


The job of the liver is to process the filtered blood throughout the human body (18). In the process of filtering the blood, the liver detoxifies the substances that can harm the body, metabolize nutrients and make proteins for blood clotting (19). Additionally, there are many other important functions it performs.

When the liver cells that contain enzymes, which actually drive all these reactions, are destroyed or somehow damaged, these proteins or enzymes start leaking into the blood (20). This is why they can be measured with the use of blood tests.

When a liver blood test is performed, doctors check for two main enzymes of this organ: aspartate aminotransferase and alanine aminotransferase (20). The first is also called SGOT and is found in many tissues besides the liver, including the muscles (21). The latter is also called SGPT and it is only found in the liver (22).

When it comes to these two tests, liver damage is existent when they are elevated.

Summary: The liver filters blood in the body. During the process of filtering, the liver detoxifies substances that harm the body, metabolize nutrients, and make proteins for blood clotting. When the liver cells are destroyed or damaged, the enzymes start leaking into the blood. Hence, this is why they can be measured in a blood test. Elevated ALT and AST determines liver damage is occurring.

Alkaline Phosphatase, GGT, and 5′ Nucleotidase

The liver also produces bile (23). The bile’s purpose is to digest the fat in the body. Bile is stored in the gallbladder, which is located underneath the liver but it actually flows through the liver in ducts (small tubes’ system) (24).

When the liver is damaged, the bile flow is often slower or even completely blocked (25). When this happens, the level of alkaline phosphatase, gamma-glutamyl transpeptidase, and 5′ nucleotidase are increased (26).

The condition of these enzymes in the blood is checked by liver tests. Out of the three, the most commonly tested enzyme is alkaline phosphatase (27). When this enzyme is elevated there is a certain problem with the bile flow (28). The same is the case of an increase in 5′ nucleotidase and GGT (29).

Bile flow issues show problems with the gallbladder, the liver or the tubes that connect the two.

Summary: The liver also makes bile. Bile digests fat in the body and is stored in the gallbladder, located underneath the liver. When liver damage occurs, the bile flow is slower or can even be blocked off. The level of alkaline phosphatase, GGT, and 5’nucleotidase increases when this occurs. Alkaline phosphatase is the most commonly tested of the three.

PT and INR

As we said, the liver has many functions. Besides the ones we mentioned above, the liver also creates proteins, which aid the blood clotting (30). The tests that check the function of the liver check for its ability to make such proteins.

These tests are prothrombin time or PT and International normalized ratio or INR (31). The first is a test that examines the time that it takes for the blood to clot (32). This test is done in a lab, under specific conditions and with a blood sample from the patient. The prothrombin test takes longer time if there are some factors of decreased blood clotting.

The latter is a standardized way of reporting the PT that makes all labs share and compare results with each other (33).

When the liver starts failing the clotting process, the PT and the INR will rise.

Summary: The liver also creates proteins that aid in blood clotting. Prothrombin time (PT) and international normalized ratio (INR) are tested to determine if proteins are being made by the liver. If they are not, these tests become elevated.


Another function of the liver is to create a protein that will circulate in the blood, which is called albumin (34). When the patients have a severe chronic disease of the liver, such as hepatitis C virus, they have low albumin levels (35).

This test shows whether the body produces normal or reduced levels of albumin (36). However, even if the test shows abnormal amounts, this does not necessarily mean that the patient has hepatitis C. The test is not a very reliable one when it comes to diagnosing a particular liver disease.

Summary: The liver also creates a protein that circulates in the blood called albumin. Patients with severe chronic disease of the liver, such as the hepatitis C virus, have low albumin levels. This does not determine if they have hepatitis C, rather it gives information on whether the liver is producing this protein. If the levels are off, this determines an issue with the liver.


The last one is a product that comes as a waste when the red blood cells break down (37). The liver uses this waste by processing it on its way to be excreted in the stool. When checking the bilirubin, tests can show elevated bilirubin blood levels in cases where the bile flow is impaired (38). The thing is, bilirubin also flows through the bile ducts and it is actually dissolved in the bile.

When the bile flow is impaired, the patient may be suffering from a liver, gallbladder or bile system disease (39). In cases where the bilirubin is high, the person may develop jaundice and have yellow skin (40).

Summary: When red blood cells break down, bilirubin is a waste product. Bilirubin levels can be elevated in cases where the bile flow is impaired. Bilirubin can also flow through the bile ducts and dissolve in the bile. So if bile flow is impaired, the patient could be suffering from liver, gallbladder, or bile system issues. Jaundice or yellow skin is a side effect of elevated bilirubin levels.

When Should You Call the Doctor?

If you are diagnosed with hepatitis C, there are several cases where you should immediately get a medical consult. These cases are:

  • When you are having hallucinations
  • When you are extremely confused
  • When you are vomiting blood
  • When you have rectum bleeding

Who Can Diagnose Hepatitis C?

If you think you may have been infected with the virus, the first thing you need to do is consult a doctor. You can take a home test for hepatitis C, but the best way to make sure that you do not have the infection is by consulting a specialist. People who can diagnose you with hepatitis C are:

  • Your family physician
  • Pediatrician
  • Physician assistant
  • Specialist for infectious diseases
  • Internist
  • Gastroenterologist
  • Nurse practitioner
  • Hepatologist
  • Gynecologist

Not treating the hepatitis C infection is a dangerous thing and it is best to take things under control immediately. In some cases, people who are infected with the disease terminate it with treatment, while in others, this condition turns into a chronic one. Considering that there are often no symptoms at the beginning, it is best that you immediately check for infection if you suspect that you may have been infected with hepatitis C.