Chronic Hepatitis B

If you have HBV for six months, you are chronically infected (a carrier), but since you can have HBV without any hepatitis b symptoms, the only way to truly know if you are chronically infected is to have a blood test. The blood test is easy to get-if you donate blood, for example, the blood bank will test for HBV-but, like everything else about hepatitis, interpreting the test is complicated. It isn’t just a question of “you got it or you don’t.”

There are three standard blood tests for HBV. The first is to see if HBsAg (hepatitis B surface antigen) is present in your blood. If it is, then you are presently HBV infected and you are able to pass the disease on to others. The second test is for the presence of anti-HBc or HBcAb (antibody to the hepatitis B core antigen). If this is present, it indicates that you have had contact with the HBV virus. But this test is very difficult to interpret, and often results in false positives. What it means often depends on the results of the other two tests.

The third is the test for the anti-HBs or HBsAb (the antibody to hepatitis B surface antigen). If this is positive, it means you have had HBV (or the vaccine for it) and you are immune to the disease. You can’t pass it on to other people. If a blood bank finds positive results on either of the first two tests, that’s all they need to know-they won’t accept your blood. But you have to know more: you have to know exactly which test you tested positive for. The chart below summarizes the interpretation of the HBV blood test results.

Needless to say (but we’ll say it anyway), you can’t interpret these results by yourself. A doctor must interpret them for you, and he or she may want to do further blood tests before deciding on a course of action.

When you donate blood, your blood must by law be tested for HBsAg by a specific, quite sensitive FDA approved method. If the first test is “nonreactive” -that is, if it shows no HBsAg, then your blood will be used (Provided all other requirements are met). But if the first test is “reactive” for the antibody, the test will be perfonned twice more. If both tests are nonreactive, the blood can be used. But if either or both tests are reactive, the unit of blood cannot be used. Before you are notified of the result, one more test will be performed, just to make sure. If this test shows HBsAg, then you will be informed that you cannot donate blood, now or ever. The CDC recommends that this information be presented to you in a sealed letter or in a face-to-face interview. You will be infonned in the interview or the letter that you might have chronic HBV, and that you might be infectious to others. You will be told about the vaccine that is available for your household members or sexual partners. Finally, the letter or interviewer will suggest medical follow-up and tell you where you can get it

If it is detennined that you are a carrier, you should see a doctor immediately, and then once every six months after that. The doctor will want to do several things. First, he’ll test your blood once again. Sometimes this test will come up negative, indicating that there was a transient acute infection. Then he will want to run the test to determine whether you have the chronic or acute variety of the illness. The doctor will be most interested in seeing how your liver is functioning, since this is the organ that the HBV virus attacks and destroys. You can see your regular doctor, but you will also want to consult with a gastroentefqlogist, preferably an expert in hepatology, the subspecialty that deals with diseases of the liver. You will want to avoid alcohol, which can cause liver damage. And you will have to infonn your doctor of any medicines you are taking, including over-the-counter drugs, because many drugs can cause stress to the liver. As long as you remain a “healthy carrier,” which could be the rest of your life, this will be your procedure.