Hepatitis B and HIV coinfection

Hepatitis B and HIV coinfection means living with both viruses at the same time. It is a common situation, because the two share the same routes of transmission, and today it has a clear answer: antiretroviral therapy should be chosen so that it controls HIV and the hepatitis B virus at once.

The most important thing to know is this. Carrying both viruses together speeds up liver damage and raises the risk of cirrhosis and liver cancer. The good news is that certain drugs, in particular tenofovir combined with emtricitabine or lamivudine, treat both viruses at the same time. That is why current management aims to make sure that, as soon as coinfection is detected, antiretroviral therapy always includes one of these medications.

Why do hepatitis B and HIV occur together?

Hepatitis B and HIV are transmitted through the same routes: contact with blood, sex without protection, and from mother to child during delivery. That is why finding both viruses in the same person is common. An estimated 5 to 10% of people living with HIV worldwide also have chronic hepatitis B, and the proportion is higher among those infected through sex or through sharing needles.

Why is having both viruses more serious?

HIV changes the natural course of hepatitis B, and almost always for the worse. In a person with HIV, hepatitis B is less likely to clear on its own, the hepatitis B viral load tends to be higher, and liver fibrosis (scarring) advances faster. The result is a greater risk of cirrhosis, of liver decompensation, of liver cancer and of liver-related death.

This risk increases when several factors come together:

• Low CD4 lymphocyte counts.
• High levels of hepatitis B virus in the blood (elevated HBV DNA).
• Persistent presence of the e antigen (HBeAg positive).
• Older age and alcohol use.

Precisely because the damage is faster, timely diagnosis and good treatment make an enormous difference for these patients.

Who should be screened?

Screening should go both ways. Everyone diagnosed with HIV should be tested for hepatitis B markers: surface antigen (HBsAg), core antibody (anti-HBc) and surface antibody (anti-HBs). Likewise, everyone with hepatitis B should be offered an HIV test.

If HBsAg is positive, the workup is completed with the hepatitis B viral load, HBeAg and anti-HBe, liver enzymes, an abdominal ultrasound and an assessment of fibrosis, which today is usually done with elastography (FibroScan) rather than a biopsy. Because hepatitis B, C, D and A share routes of transmission, these patients are also tested for hepatitis C, screened for hepatitis D, and checked for immunity to hepatitis A.

Treatment must cover both viruses

This is the core of modern management. Today nearly everyone with HIV receives antiretroviral therapy, regardless of their CD4 count. When they also have hepatitis B, that therapy must include two drugs that are active against both viruses at once.

The mainstay is tenofovir, in either of its two forms (tenofovir disoproxil, TDF, or tenofovir alafenamide, TAF), almost always combined with emtricitabine or lamivudine. This combination controls HIV replication and, at the same time, suppresses the hepatitis B virus, slows liver inflammation and reduces the risk of cirrhosis and liver cancer. Recent studies in people with coinfection confirm that tenofovir-based regimens are associated with fewer serious liver complications than regimens without it.

There are two mistakes worth avoiding in particular:

• Do not use lamivudine or emtricitabine as the only anti-hepatitis-B drug. On their own, without tenofovir, they lead the hepatitis B virus to develop resistance over time. They should always be paired with tenofovir.
• Do not stop these medications on your own. Abruptly interrupting tenofovir, emtricitabine or lamivudine can trigger a severe flare of hepatitis B, with acute liver inflammation that can become dangerous. Any change in regimen should be made by your physician and in a planned way.

Immune reconstitution

When antiretroviral therapy is started, the immune system recovers. That is the goal, but because the liver damage in hepatitis B is largely immune-mediated, this recovery can show up as a temporary rise in liver enzymes in the first weeks or months. This is called immune reconstitution and should not be confused with damage from the medications. That is why blood tests are done more often at the start of treatment.

Vaccinate against hepatitis B those who do not have it

Prevention is as important as treatment. Everyone with HIV who does not have hepatitis B or prior immunity (that is, with negative HBsAg, anti-HBc and anti-HBs) should receive the hepatitis B vaccine. Because the response to the vaccine can be weaker in HIV, reinforced schedules are used, and afterward anti-HBs is checked to confirm that the vaccine worked, with revaccination if needed. Vaccination against hepatitis A is also recommended for those without immunity.

Preventing transmission

Hepatitis B is transmitted through sex more easily than HIV. Being on treatment and having a low viral load does not replace using a condom. Sexual partners and people living in the same household should be tested and vaccinated against hepatitis B.

When cirrhosis is already present

Coinfected people who reach cirrhosis always have an indication for treatment with drugs active against hepatitis B, without exception. They also need regular ultrasound monitoring for the early detection of liver cancer, a higher risk in coinfection. Liver transplant, once considered off-limits with HIV, is today a real option for those with decompensated cirrhosis whose HIV is well controlled on treatment.

See also

• Hepatitis B
• Hepatitis C
• Cirrhosis
• Liver transplant