Detailed introduction to hepatitis D virus

Liver disease seriously endangers the human body. If the type of hepatitis is single, the treatment method will be relatively simple. However, there are many types of hepatitis, and each type causes great harm to the body, so this greatly increases the difficulty of treatment. Hepatitis is divided into five types: A, B, C, D, and E. The following will introduce the specific content of hepatitis D.

Hepatitis D is an infectious disease caused by hepatitis D virus (HDV) and hepatotropic DNA viruses such as hepatitis B virus. The disease is distributed worldwide, especially in southern Italy where it is highly endemic. The HBsAg carrier rate is relatively high in developing countries, which provides the basis for HDV infection. Our country's investigation report suggests that there is a local epidemic. The HDV infection rate of HBsAg-positive people in various places is 0% to 32%. Generally speaking, it is lower in the north and higher in the south. The incidence of HDV infection in patients with severe hepatitis and chronic liver disease is significantly higher than that in asymptomatic HBsAg carriers. It is mainly transmitted through blood transfusions and blood products, similar to the way hepatitis B is transmitted. Over-infection of HDV and HBV can aggravate liver damage and easily develop into chronic active hepatitis, cirrhosis and severe hepatitis.

Clinical manifestations

After a person is infected with HDV, the clinical manifestations are determined by the original HBV infection status. The incubation period is 4 to 20 weeks. There are two types:

1. Co-infection with HDV and HBV

It occurs when a person is infected with both HDV and HBV without any previous HDV infection, manifesting as acute hepatitis D. Its clinical symptoms are similar to those of acute hepatitis B, and elevated bilirubin and ALT may be seen twice during the course of the disease. HBsAg appears first in the serum, and then HDAg is positive in the liver. In patients in the acute phase, serum HDAg is positive for a few days and then turns negative, followed by anti-HD IgM positivity, which lasts for a short time and has a low titer. Anti-HD IgG was negative.

2. Superinfection of HDV and HBV

The clinical manifestations are diverse and may resemble acute hepatitis, chronic hepatitis, or severe hepatitis. It is more common in patients with chronic HBV infection, and its symptoms are mainly determined by whether they were chronic HBsAg carriers or patients with HB chronic liver disease before HDV infection. If the patient is a HBsAg carrier, after being infected with HDV, the symptoms will be similar to acute HBsAg-positive hepatitis, but anti-HBVIgM is negative, which is more serious than simple HBV infection. If it is HBV chronic liver disease, due to the continuous infection of HBV and the continuous replication of HDV, the existing liver tissue lesions are aggravated, which can manifest as an acute attack of hepatitis or accelerate the development to chronic active liver and cirrhosis. Therefore, if a patient with chronic hepatitis B is originally stable but suddenly has worsening symptoms or even liver failure, which is quite similar to severe hepatitis, the possibility of superinfection with HDV should be considered.

The medical community does not have a good treatment for type 2 hepatitis, so prevention is the key. It is recommended that the general public get vaccinated to prevent the virus from invading the body, and pay attention to personal hygiene. When eating out, try to use your own bowl and chopsticks, do not use other people's water cups or daily necessities, and go to the hospital regularly for liver function tests.