A Physicians Guide to Hepatitis B
UPDATED! The 2013 Physician’s Guide to Hepatitis B is a popular handbook that provides health care providers with the latest information on the incidence, transmission, detection, prevention, and management of hepatitis B and liver cancer. The handbook has been praised for being comprehensive while retaining an easy-to-read and user-friendly format. The Centers for Disease Control and Prevention (CDC), the leading federal agency charged with promoting the health and safety of the American people, has even placed this guide on their website for use by all health professionals and government agencies.
To download a copy of the 2013 Physician's Guide, click here
Topics
HBsAg and anti-HBs tests
Pregnant patients
anti-HBc tests
Vaccines
Avoiding needlestick injuries
When is anti-viral treatment for chronic HBV appropriate
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Blood Tests
1. Hepatitis B surface antigen (HBsAg): screening test
The HBsAg test is the ONLY way to definitively diagnose chronic HBV infection. By definition, if your patient remains HBsAg-positive for more than 6 months, then he/she has developed chronic (lifelong) infection. Since most Asians became infected at birth or during early childhood, most of your Asian patients who test positive for HBsAg will have chronic HBV infection. HBsAg-positive patients require counseling and medical management for chronic HBV infection to reduce their risk for chronic liver disease.
2. Hepatitis B surface antibody (anti-HBs): tests for immunity
The anti-HBs test will tell if your patient is protected against HBV. Anti-HBs can be produced in response to vaccination or recovery from an acute hepatitis B infection.
Quick Test Results
Result |
Interpretation |
HBsAg (+) |
Chronic HBV infection * |
HBsAg (-) |
Immune to HBV |
HBsAg (-) |
Unprotected; need vaccination |
HBsAg (+) |
Chronic HBV infection * |
* If HBsAg remains positive for 6 months
If your patient is not infected and not protected, start the hepatitis B vaccination series. In addition, you can help raise awareness by having educational brochures in the waiting area and around the office for people to pick up. The Asian Liver Center at Stanford University provides educational brochures about hepatitis B free of charge. Click on the following link to order some: http://liver.stanford.edu/Public/brochureorder.html.
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Hepatitis B core antibody (anti-HBc) blood tests
Some HBV blood panels may include two additional tests:
- The total hepatitis B core antibody (total anti-HBc) test tells if your patient has been previously infected with HBV, which is useful for screening potential blood donors (the U.S. does not allow people with past HBV infections to donate blood – even if they have recovered). The test by itself does not tell if your patient is protected against HBV infection.
- The hepatitis B core IgM antibody (IgM anti-HBc) test tells if an unprotected patient has recently been infected with HBV.
Blood Test |
Result |
Interpretation |
Total anti-HBc |
Positive (+) |
Previous exposure to HBV (the test alone does indicate whether or not the patient has persistent infection or if immunity has developed); not a candidate for donating blood |
Negative (-) |
Never been infected with HBV; candidate for donating blood |
|
IgM anti-HBc |
Positive (+) |
Recently acquired acute HBV infection |
A positive total anti-HBc test or IgM anti-HBc test does not tell if your patient has chronic HBV infection – only an HBsAg test that remains positive for over six months can do this. If your patient has acute HBV infection, his/her infection may or may not become lifelong.
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Vaccination
Hepatitis B Vaccines
Engerix-B and Recombivax HBV: HBV only
For any age: These single-antigen hepatitis B vaccines are typically given as a 3-shot series. These are the only vaccines acceptable for birth dose. For adolescents 11-15 years old, an alternative 2-dose Recombivax HBV regimen may be used. Energix-B and Recombix HB can be used interchangeably and administered concurrently with hepatitis B immune globulin (HBIG) or other vaccines.
Combination Vaccines
Pediarix: HBV + diphtheria + tetanus + pertussis + polio
For children (6 weeks – 7 years of age): All newborns, regardless of their mother’s HBsAg status, should receive a birth dose of the hepatitis B vaccine with either Engerix-B or Recombivax HBV. After the initial birth dose, a 3-dose Comvax regimen can be used to complete the series.
Twinrix: HBV + hepatitis A
For adults (18 years of age and older): Suitable for anyone seeking protection from HBV and/or hepatitis A virus (HAV), and high risk groups such as travelers to countries of high endemicity, men who have sex with men, injection drug users, medical or laboratory workers handling HBV or HAV, and patients with chronic liver disease. Whereas hepatitis B vaccine is usually given in three shots and hepatitis A vaccine is given in two shots, Twinrix is given as a 3-shot series.
If your patient is NOT immune after vaccination
Although uncommon, about 5% of people who complete the hepatitis B vaccination series may not acquire immunity (anti-HBs levels are <10 mIU/mL). In these cases, take the following steps:
1. Administer another 3-shot series at the normal schedule using a different hepatitis B vaccine.
2. Test again for anti-HBs 1-2 months after completion of the series to confirm protection. 44-100% of these patients will successfully develop immunity.
The rare group of people not protected after six doses should take care to avoid HBV transmission (e.g. cover wounds, use condoms). Nonresponders exposed to HBV-infected bodily fluids should get the hepatitis B immune globulin (HBIG) shot to prevent infection.
Postexposure prophylaxis
HBIG (Hepatitis B Immune Globulin)
For any age: Provides passively acquired anti-HBs and temporary protection against HBV infection (i.e. 3-6 months). HBIG is typically administered along with hepatitis B vaccine after unvaccinated persons are exposed to blood or bodily fluids infected with HBV (e.g. when infants are born to HBsAg-positive women, after needlestick injuries, and after sexual contact with an infected person). HBIG alone is the primary means of protection for nonresponders to hepatitis B vaccine.
Notes regarding preterm infants weighing less than 2000 grams:
- For premature infants born to HBsAg-negative mothers: delay administration of the vaccine series until age 1 month or hospital discharge, then resume the series according to the schedule.
- For premature infants born to HBsAg-positive mothers: give the HBIG shot and HBV vaccine within 12 hours of birth, then start the vaccine series beginning at age 1-2 months (do not count birth dose as part of the vaccine series).
Vaccine administration and storage
Follow these simple precautions to protect your patients:
- Shake the vaccine before use. Hepatitis B vaccine normally looks cloudy, but if the vaccine stands for a long time, it may separate from the liquid and look like fine sand at the bottom of the vial.
- Do NOT freeze or expose to freezing temperatures. Store hepatitis B vaccine at 2-8°C (36-46°F). The “shake test” will determine if the vaccine has been damaged by freezing. If the vaccine fails the shake test (the vaccine and liquid do not mix) you must discard it.
- Administer the hepatitis B vaccine intramuscularly (i.e. in the arm for children and adults, and in the thigh for infants). It is ineffective if given subcutaneously in fatty tissue (i.e. in the buttocks).
- Do NOT reuse needles. Always use sterile syringes, preferably with auto-disable features to prevent reuse.
- Immediately dispose of used needles into puncture-resistant safety containers.
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Avoiding Needlestick Injuries
How to protect yourself:
- Practice universal precautions to prevent transmission of HBV and other bloodborne pathogens, including safe needle handling and the use of gloves.
- Vaccinate all health care workers against HBV, then test for anti-HBs 1-2 months after completion of the vaccination series to confirm protection (anti-HBs level ≥ 10mIU/mL).
What to do if you are exposed to HBV-infected blood through a needlestick or other sharps injury:
- If you have already developed immunity from prior vaccination or resolved infection (anti-HBs level ≥ 10mIU/mL), no treatment is necessary
- If you are unvaccinated, have not completed the 3-shot series, or are unsure of your vaccination status:
- Get the HBIG shot (0.06mL/kg) within 24 hours of exposure
- Complete the hepatitis B vaccination series on schedule
- Test for HBsAg and anti-HBs 1-2 months after the last dose of hepatitis B vaccine
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When is antiviral treatment not appropriate
Normal ALT
There is no evidence to support treatment of these patients, regardless of their HBV DNA or HBeAg status. However, they are still at risk for liver cancer and flare up of hepatitis, and should be screened regularly.
When is treatment for chronic HBV appropriate
Elevated ALT (>2x normal)
Low or undetectable HBV DNA
HBeAg (+)
These chronic HBV patients show signs of active liver damage associated with high viral activity and it is reasonable to consider treatment by oral antivirals or injection immunostimulators.
Elevated ALT (>2x normal)
Elevated HBV DNA (>20,000 IU/mL)
HBeAg (-)
These chronic HBV patients show signs of active liver damage caused by a mutant strain of HBV that does not secrete HBeAg. It is reasonable to consider treatment by oral antivirals or injection immunostimulators.
Cirrhosis
Normal or elevated ALT
Detectable HBV DNA
For patients with compensated or decompensated cirrhosis consider HBV treatment by oral antivirals, regardless of HBeAg.
Cancer chemotherapy
Normal or elevated ALT
Detectable or undetectable HBV DNA
When the immune system is suppressed during chemotherapy, flare-up of the HBV infection can lead to fulminant hepatitis and death. Therefore, HBsAg-positive patients undergoing chemotherapy should be placed on prophylactic oral antiviral treatment, regardless of pre-treatment ALT, HBV DNA or HBeAg levels.