Hepatitis D Virus Coinfection and Superinfection

Abstract

HDV is a defective RNA pathogen requiring the simultaneous presence of HBV to complete its life cycle. Two major specific patterns of infection have been described: the coinfection with HDV and HBV of a susceptible, anti-HBs-negative individual, or the HDV superinfection of a chronic HBV carrier. Coinfection mostly leads to the eradication of both agents, whereas the majority of patients with HDV superinfection evolve to chronic HDV infection and hepatitis. Chronic HDV infection worsens the preexisting HBV-related liver damage. HDV-associated chronic liver disease (chronic hepatitis D) is characterized by necroinflammation and the relentless deposition of collagen culminating, within a few decades, into the development of cirrhosis and hepatocellular carcinoma. H epatitis D virus (HDV) infection characterizes a subgroup of hepatitis B surface antigen (HBsAg)-positive patients affected by a frequently aggressive form of chronic liver damage (hepatitis D). Because HDV particle assembly and release are dependent on the obligatory presence of HBV within the same hepatocytes, a productive HDV infection is invariably associated with HBV infection. Two major patterns of infection have been described: coinfection with HBV and HDV, or superinfection with HDV of a person chronically infected with HBV. A third minor pattern or helper-independent HDV infection has been reported in the liver transplant setting. Although its existence is questioned, it will be briefly discussed in view of its historical interest. ACUTE HEPATITIS DAcute hepatitis D caused by HBV/HDV coinfection occurs on the simultaneous infection with both HBV and HDV of an individual who is susceptible to HBV (and therefore anti-HBs negative) (Fig. 1). From a clinical standpoint, this entity is indistinguishable from an acute hepatitis B (Smedile et al. 1982). Acute hepatitis D occurs after an incubation time of 1-2 mo. The preicteric phase is characterized by nonspecific symptoms such as fatigue, lethargy, digestive symptoms (anorexia, nausea), and the appearance of the usual biochemical markers, such as elevated serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The icteric phase, which is not always observed,

Long‐term clinical outcomes in patients with chronic hepatitis delta: the role of persistent viraemia

“…Hepatitis delta virus (HDV) is an RNA‐defective virus that requires the simultaneous presence of hepatitis B virus (HBV) to be infectious and fully express its pathogenicity and, therefore, hepatitis D infection always occurs in the presence of HBV . HDV infection can be acquired by patients already infected with HBV (superinfection) or through simultaneous infection by both HDV and HBV (coinfection) . Both superinfection and coinfection can initially have similar symptomatology.…”

“…The outcome of HDV/HBV‐coinfected patients is typically benign with acute self‐limited hepatitis and few cases of acute liver failure . In contrast, most HDV superinfections evolve to chronicity and can sometimes cause liver failure or significant worsening of underlying chronic hepatitis B . Several cohort studies in which chronic hepatitis delta patients were followed for a variable time period have analysed the cumulative rate of hepatic decompensation and liver‐related deaths .…”

Vibration‐controlled transient elastography for the detection of cirrhosis in chronic hepatitis D infection

“…In HDV, VCTE has not yet been validated and two recent studies evaluating noninvasive serum tests have demonstrated inadequate performance . Concerns exist on whether these noninvasive tests can be clinically useful in chronic HDV since HDV is associated with severe necroinflammation which may skew testing results . It remains unclear if noninvasive testing, especially VCTE, has any clinical value in chronic HDV and if the pre‐existing VCTE cut‐offs for HBV or HCV are applicable to HDV.…”

Liver Fibrosis and Progression of Liver Disease in Patients with Hepatitis Delta - Results from a Retrospective Study in Romania

“…(8) In our patient population with chronic hepatitis B and delta, we recorded a steady decrease of thrombocyte counts over time, with 7,000/µL in 1.3 years and 17,000/µL in 2.8 years after diagnosing HDV infection. This information is derived from a patient population that already presented some degree of fibrosis at baseline, but notably only 21.1% of the patients presented cirrhosis.…”