Hepatitis D
By Howard J. Worman, M. D.
The Hepatitis D virus (also called delta virus) is a small circular RNA virus.
The Hepatitis D virus is replication defective and therefore cannot propagate
in the absence of another virus. In humans, Hepatitis D virus infection only
occurs in the presence of Hepatitis B infection.
Hepatitis D virus infection is transmitted by blood and blood products.
The risk factors for infection are similar to those for Hepatitis B virus infection.
The Hepatitis D virus most often infects intravenous drug users.
A patient can acquire Hepatitis D virus infection at the same time as he/she
is infected with the Hepatitis B virus. This is called co-infection. A patient
with Hepatitis B can be infected with Hepatitis D virus at any time after acute
Hepatitis B virus infection. This is called super-infection.
Hepatitis D virus super- infection should be suspected in a patient with chronic
Hepatitis B whose condition suddenly worsens. There is usually an obvious history
of continued exposure to blood or blood products (eg. an active intravenous
drug user). A particularly aggressive acute Hepatitis B infection could suggest
Hepatitis D co- infection. Co-infection or super-infection with Hepatitis D
virus in a patient with Hepatitis B is diagnosed by the presence of antibodies
against the Hepatitis D virus. IgM antibodies indicate acute infection.
Interferon-alpha is used to treat patients with chronic Hepatitis B and Hepatitis
D infection. Some studies have suggested that a dose higher than that usually
used for Hepatitis B infection may be beneficial.
Copyright, 1995, Columbia University Division of Gastroenterology
Hepatitis D/Howard J. Worman, M.D./hjw14@columbia.edu
|