Hepatitis D

Next up, Hepatitis D!
Hepatitis D virus (HDV), also known as Delta agent is a type of virus causes symptoms only in people who also have a Hepatitis B infection. HDV may result in the worsening of an acute or chronic hepatitis B liver disease. Hepatitis D infects about 15 million people worldwide. It occurs in 5% of people who carry hepatitis B.




The HDV virion is enveloped and spherical with a diameter of about 22 nm  Membrane proteins are originated from the HBV helper virus.

How does this Delta agent replicate? 

1. Virus attaches to host receptors though Major surface antigen.
2. Fusion of virus membrane with the cellular membrane; ribonucleocapsid is released in the cytoplasm and migrates to the nucleus.
3. S-HDAg is expressed, promoting viral transcription and replication by host DNA-dependent RNA polymerase II
4. later, genomic RNA is edited by host ADAR1, leading to L-HDAg expression which induce packaging of HDV genome at the RE.
5. Budding by helper HBV proteins.

 


Risk factors of Hepatitis D includes :

• Abusing intravenous (IV) or injection drugs
• Being infected while pregnant (the mother can pass the virus to the baby)
• Carrying the hepatitis B virus
• Men having sexual intercourse with other men
• Receiving many blood transfusions

The symptoms of Hepatitis D are similar to those of Hepatitis B, just that it makes the symptoms more severe. The symptoms are :

• Abdominal pain
• Dark-colored urine
• Fatigue
• Jaundice
• Joint pain
• Loss of appetite
• Nausea
• Vomiting
  
  
  Treatment?
   Many of the medicines used to treat hepatitis B are not helpful for treating hepatitis D, however, people with long-term HDV infection may receive a medicine called alpha interferon for up to 12 months. A liver transplant for end-stage chronic hepatitis B may be more effective.
  
  How does it affect people?

People with an acute HDV infection usually get better over 2 to 3 weeks and liver enzyme levels will return to normal within 16 weeks. However, about 10% of those who are infected with HDV may develop long-term (chronic) liver inflammation (hepatitis).

These people may also contract Chronic active hepatitis or Fulminant hepatitis.


How to prevent contracting HDV?
- Prompt diagnosis and treatment of hepatitis B infection can help prevent hepatitis D.
- Avoid intravenous drug abuse. If you use IV drugs, avoid sharing needles.
- A vaccine is available to prevent hepatitis B, which in turn prevents hepatitis D.


Jayme

Retrieved from http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001264/
Perrillo R. Hepatitis B and D. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier;2010:chap 78.
Review Date: 11/23/2010.
Reviewed by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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