(See also Causes of Hepatitis Causes of Hepatitis Hepatitis is inflammation of the liver characterized by diffuse or patchy necrosis. Hepatitis may be acute or chronic (usually defined as lasting > 6 months). Most cases of acute viral hepatitis... read more , Overview of Acute Viral Hepatitis Overview of Acute Viral Hepatitis Acute viral hepatitis is diffuse liver inflammation caused by specific hepatotropic viruses that have diverse modes of transmission and epidemiologies. A nonspecific viral prodrome is followed... read more , and Overview of Chronic Hepatitis Overview of Chronic Hepatitis Chronic hepatitis is hepatitis that lasts > 6 months. Common causes include hepatitis B and C viruses, nonalcoholic steatohepatitis (NASH), alcohol-related liver disease, and autoimmune liver... read more .)
Hepatitis D is usually transmitted by parenteral or mucosal contact with infected blood or body fluids. Infected hepatocytes contain delta particles coated with hepatitis B surface antigen (HBsAg).
Prevalence of hepatitis D virus (HDV) varies widely geographically, with endemic pockets in several countries. Parenteral drug users are at relatively high risk, but HDV, unlike hepatitis B virus (HBV), has not widely permeated the MSM (men-who-have-sex-with-men) community.
Symptoms and Signs of Hepatitis D
Acute hepatitis D infection typically manifests as
An acute exacerbation in chronic HBV carriers (superinfection)
Diagnosis of Hepatitis D
Serologic testing
In the initial diagnosis of acute hepatitis Initial diagnosis of acute hepatitis Acute viral hepatitis is diffuse liver inflammation caused by specific hepatotropic viruses that have diverse modes of transmission and epidemiologies. A nonspecific viral prodrome is followed... read more , viral hepatitis should be differentiated from other disorders causing jaundice (see figure Simplified approach to possible acute viral hepatitis Simplified diagnostic approach to possible acute viral hepatitis 
). If acute viral hepatitis is suspected, the following tests are done to screen for hepatitis viruses A, B, and C:
IgM antibody to hepatitis A virus (IgM anti-HAV)
Hepatitis B surface antigen (HBsAg)
IgM antibody to hepatitis B core (IgM anti-HBc)
Antibody to hepatitis C virus (anti-HCV) and hepatitis C RNA (HCV RNA) polymerase chain reaction
If serologic tests for hepatitis B Hepatitis B Serology* 
confirm infection and clinical manifestations are severe, antibody to HDV (anti-HDV) levels should be measured. Anti-HDV implies active infection. It may not be detectable until weeks after the acute illness.
Treatment of Hepatitis D
Supportive care
No treatments attenuate acute viral hepatitis, including hepatitis D. Alcohol should be avoided because it can increase liver damage. Restrictions on diet or activity, including commonly prescribed bed rest, have no scientific basis.
The only drug widely recommended for treatment of chronic hepatitis D is interferon-alfa, although pegylated interferon-alpha is likely equally effective. Treatment for 1 year is recommended, although whether longer treatment courses are more effective has not been established. Bulevirtide is available for treatment of hepatitis D in Europe. Hepatitis D is also treated in the context of clinical trials.
Prevention of Hepatitis D
No product exists for immunoprophylaxis of hepatitis D. However, prevention of HBV infection Prevention Hepatitis B is caused by a DNA virus that is often parenterally transmitted. It causes typical symptoms of viral hepatitis, including anorexia, malaise, and jaundice. Fulminant hepatitis and... read more prevents HDV infection.
Key Points
Hepatitis D occurs only with hepatitis B.
Suspect hepatitis D particularly when cases of hepatitis B are severe or when symptoms of chronic hepatitis B are worsening.
Treat and prevent infection as for hepatitis B.
