Hepatitis D (thesaurus synonyms: acute viral hepatitis B with concomitant infection by delta virus; HBV/HDV coinfection; HD virus infection; HD virus infection; hepatitis B and D; hepatitis delta; viral hepatitis B with delta virus; ICD-10-GM B16.0: acute viral hepatitis B with delta virus (concomitant infection) and with coma hepaticum; CD-10-GM B16. 1: Acute viral hepatitis B with delta virus (concomitant infection) without coma hepaticum) is an inflammation of the liver with the hepatitis delta virus (HDV, formerly also called delta virus or δ-agent), which can occur as a coinfection (concomitant infection) of hepatitis B. Hepatitis delta virus is an incomplete (“naked”) RNA virus (viroid) and requires the envelope of hepatitis B virus for replication. Hepatitis D infection cannot occur without hepatitis B infection. Eight HDV genotypes can be distinguished. Occurrence: Hepatitis D virus infection occurs worldwide, but is rare in Germany. The infection occurs endemically (“clustered occurrence of the disease”) in the Mediterranean region, the Middle East, Pakistan, Mongolia and the Amazon region. Approximately 5% of those infected with hepatitis B are also infected with the hepatitis D virus. There are also regions (Brazil and Romania) where approximately 40% of hepatitis B infected persons are co-infected with hepatitis D. In Europe, up to 12% of people infected with hepatitis B are also infected with hepatitis D virus. Transmission of the pathogen (route of infection) occurs parenterally through blood (via infusions/transfusions), sexually (sexual intercourse), and perinatally (around or during childbirth) from the mother to the unborn/newborn. High-risk groups include primarily medical personnel, drug abusers, and homosexuals. The incubation period (time from infection to onset of disease) is usually between 4-12 weeks (-4 months). Usually, the incubation period is shorter in superinfection than in coinfection (simultaneous infection with hepatitis B and D). The following two forms of infection can be distinguished:
- Hepatitis delta virus can occur simultaneously with hepatitis B infection (coinfection, simultaneous infection).
- Hepatitis delta virus can infect a hepatitis B virus carrier in the course (superinfection).
- Furthermore, both forms can occur acutely and chronically
Course and prognosis: acute hepatitis B/hepatitis D co is symptomatic and often shows a severe course. The rate of chronicity of hepatitis B / hepatitis D co-infection is up to five percent. It is equivalent to the rate of chronification of hepatitis B infection alone. Chronic hepatitis D infection is present when HDV RNA is detectable in the blood for more than six months. Progression (progression) within 5 to 10 years to cirrhosis (end-stage chronic liver disease) is faster than with HBV monoinfection. It also leads to earlier onset of hepatocellular carcinoma (HCC). The prognosis of hepatitis B/hepatitis D co/superinfection (2-10%) is worse than that of hepatitis B infection alone (increased fulminant hepatitis with tendency to chronicity and thus transition to cirrhosis). In these individuals, the lethality (mortality related to the total number of people with the disease) is about ten times higher than in individuals with hepatitis B infection alone. The chronicity of hepatitis D superinfection is approximately 90%. The prognosis of hepatitis D with simultaneous infection is 95% cure; in the presence of superinfection, the chances of cure are low. Vaccination: Vaccination against hepatitis B protects against hepatitis D at the same time. Hepatitis B immunoglobulin is available for hepatitis B postexposure prophylaxis (passive immunization; to prevent disease in persons who are not protected against hepatitis B by vaccination but have been exposed to it). In Germany, the disease is notifiable according to the Infection Protection Act (IfSG). Notification must be made by name in the event of suspected illness, illness and death.