Hepatitis D

Description

Hepatitis is a general term meaning inflammation of the liver and can be caused by a variety of different viruses such as hepatitis A, B, C, D and E. Since the development of jaundice is a characteristic feature of liver disease, a correct diagnosis can only be made by testing patients’ sera for the presence of specificantigens and anti-viral antibodies.

Also referred to as hepatitis D virus (HDV) and classified as Hepatitis delta virus, is a disease caused by a small circular enveloped RNA virus. It is one of five known hepatitis viruses: A, B, C, D, and E. HDV is considered to be a subviral satellite because it can propagate only in the presence of the hepatitis B virus (HBV). Transmission of HDV can occur either via simultaneous infection with HBV (coinfection) or superimposed on chronic hepatitis B or hepatitis B carrier state (superinfection).

Hepatitis D

The viruslike delta agent was subsequently shown to be associated with the most severe forms of acute and chronic hepatitis in many HBsAg-positive patients. The disease it caused was designated delta or type D hepatitis.

Causes
Hepatitis D or delta hepatitis is caused by the hepatitis delta virus (HDV), a defective RNA virus. HDV requires the help of a hepadnavirus like hepatitis B virus(HBV) for its own replication.

HDV is transmitted percutaneously or sexually through contact with infected blood or blood products.

Blood is potentially infectious during all phases of active hepatitis D infection. Peak infectivity probably occurs just before the onset of acute disease.

Chronic HBV carriers are at risk for infection with HDV.

Individuals who are not infected with HBV, and have not been immunized against HBV, are at risk of infection with HBV with simultaneous or subsequent infection with HDV.

Since HDV absolutely requires the support of a hepadnavirus for its own replication, inoculation with HDV in the absence of HBV will not cause hepatitis D. Alone, the viral genome indeed replicates in a helper-independent manner, but virus particles are not released.

Transmission
  • The routes of transmission of hepatitis D are similar to those for hepatitis B. Infection is largely restricted to persons at high risk of hepatitis B infection, particularly injecting drug users and persons receiving clotting factor concentrates. Worldwide more than 15 million people are co-infected. HDV is rare in most developed countries, and is mostly associated with intravenous drug use. However, HDV is much more common in the immediate Mediterranean region, sub-Saharan Africa, the Middle East, and the northern part of South America. In all, about 20 million people may be infected with HDV.
Prevention

Since HDV is dependent on HBV for replication, control of HDV infection is achieved by targeting HBV infections. All measures aimed at preventing the transmission of HBV will prevent the transmission of hepatitis D. HBV vaccination is therefore recommended to avoid HBV-HDV coinfection.However, there is no effective measure to prevent HDV infection of chronic HBV carriers, and prevention of HBV-HDV superinfection can only be achieved through education to reduce risk behaviors.

Promising research results indicate that in some woodchucks immunized with recombinant purified HDAg-S complete protection is possible.

Hepatitis B Ig and HB vaccine do not protect HBV carriers from infection by HDV.

Medical Management:
  1. Targeting the causative agent of Hepatitis B may also kill the causative agent of Hepatitis D.
  2. Interferon is under investigation as a specific treatment for Hepatitis D.
  3. Acyclovir, ribavirin, lamivudine and synthetic analogues of thymosin have proved ineffective.
Nursing Management:
  1. Inform the patient and family members about the nature of the disease if the patient is taken care at home.
  2. Assist is paracentesis if indicated.
  3. Patients with cirrhosis could be in deep pain and discomfort, use of analgesics should be administered with great caution since it can worsen the liver damage.
  4. Diversionary therapy and non-pharmacological approach should be applied in managing pain.
  5. Ongoing monitoring of vital signs, abdominal girth and reminding for the routine check-up must be emphasized for effective management.