hepatitis-delta

DISEASE MECANISM

To help you better understand the mechanism of the disease, watch the video below:

HEPATITIS DELTA VIRUS IS AN INFECTIOUS DISEASE THAT REQUIRES THE PRESENCE OF HBV

HDV requires HBV surface antigen (HBsAg) as a surface protein to disseminate infection inside liver cells⁶

Once inside, the hepatitis delta virus genome (1.7 kb) is too small to code for the proteins required for its own replication and relies on the host machinery of liver cells to divide⁶

THE HEPATITIS DELTA VIRION

THE INFECTIVITY OF HDV^*8

HDV gains entry into uninfected hepatocytes using the HBsAg envelope

1. 1. L-HBsAg binds to the NTCP receptor
2. 2. This triggers cell entry resulting in the release of HDV ribonucleic protein into the hepatocyte
3. 3. HDV replication occurs

* Adapted from ref 8. ** As recommended by EASL, AASLD and the FDA

INTERPLAY BETWEEN HDV AND HBV

HDV tends to suppress HBV replication.
However, HBV viral load does not affect HDV viral load.
Treatment with NAs is ineffective in HDV.

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HEPATITIS DELTA IS A BLOOD-BORNE VIRUS THAT CAN BE TRANSMITTED THROUGH SEVERAL ROUTES^4,9

Contact with infected blood

Sources can include:
• •  Intravenous drug use
• •  Tattoo placed with nonsterile material
• •  Contact with blood products (eg, recipients of hemodialysis)
Sexual contact with an infected individual
Mother-child transmission (rare)

NON-DISEASE-SPECIFIC SYMPTOMS THAT MAY OCCUR IN A HEPATITIS DELTA INFECTION¹⁰

• •  Fever
• •  Fatigue
• •  Loss of appetite
• •  Nausea
• •  Vomiting
• •  Abdominal pain
• •  Dark urine
• •  Clay-colored bowel movements
• •  Joint Pain
• •  Jaundice

BECAUSE OF THE SEVERITY OF HDV, SCREENING IS URGENTLY NEEDED

Screening HBV patients helps identify those who can be offered appropriate management¹¹

EASL guidelines recommend that ALL HBV-infected patients should be screened for HDV ¹²

Recommendations AFEF 2020¹³

• • All HBV carriers should be screened for HDV infection.
• • This screening should be periodic in populations at risk (drug addiction, multiple sexual partners)

HDV SCREENING IS CRITICAL TO IDENTIFY HBV-POSITIVE INDIVIDUALS AT RISK FOR RAPID DISEASE PROGRESSION^14,15

Screening and diagnosis for HDV involves two steps:

• HDV antibody testing – screening for prior/current HDV infection
• HDV RNA testing – confirm active HDV infection

A blood test, called an HDV antibody test, is used to find out if someone has ever been infected with the hepatitis D virus. The HDV antibody test, sometimes called the anti-HDV test, looks for antibodies to the hepatitis D virus in blood. Antibodies are chemicals released into the bloodstream when someone gets infected. Test results can take anywhere from a few days to a few weeks to come back.

If the antibody test is reactive or positive, you need an additional test to see if you currently have hepatitis D. This test is called a nucleic acid test (NAT) for HDV RNA. Another name used for this test is a PCR test.

If the HDV RNA test is positive - you now have the virus in your blood.