Hepatitis D (Delta)

Key Features

• Hepatitis D virus (HDV) causes hepatitis only in the presence of hepatitis B surface antigen (HBsAg); it is cleared when the latter is cleared

• May coinfect with hepatitis B virus (HBV) or may superinfect a person with chronic hepatitis B, usually by percutaneous exposure

• Patients with long-standing chronic hepatitis D and B often have inactive cirrhosis and are at risk for decompensation and hepatocellular carcinoma

• Three-fold increased risk of hepatocellular carcinoma

Clinical Findings

• When acute hepatitis D is coincident with acute HBV infection, the infection is generally similar in severity to acute hepatitis B alone

• In chronic hepatitis B, superinfection by HDV appears to carry a worse short-term prognosis, often resulting in acute liver failure or severe chronic hepatitis that progresses rapidly to cirrhosis

Diagnosis

• Made by detecting antibodies to hepatitis D antigen (anti-HDV) or, where available, hepatitis D antigen (HDAg) or HDV RNA in serum

Treatment

• Peginterferon alfa-2b (1.5 mcg/kg/wk for 48 weeks) may lead to normalization of serum aminotransferase levels, histologic improvement, and elimination of HDV RNA from serum in 20–50% of patients with chronic hepatitis D

• However, relapse may occur and tolerance is poor

• Nucleoside and nucleotide analogs are not effective in treating chronic hepatitis D