MedGen

Presence of a protracted or persistent infection by a pathogen potentially related to an underlying abnormality of the immune system that is not able to clear the infection. [from HPO]

MARCH is an autosomal recessive lethal congenital disorder characterized by severe hydranencephaly with almost complete absence of the cerebral hemispheres, which are replaced by fluid, relative preservation of the posterior fossa structures, and renal dysplasia or agenesis. Affected fetuses either die in utero or shortly after birth, and show arthrogryposis and features consistent with anhydramnios. Histologic examination of residual brain tissue shows multinucleated neurons resulting from impaired cytokinesis (summary by Frosk et al., 2017). [from OMIM]

More than 2 billion people have been infected with the hepatitis B virus (HBV; see 610424), and more than 350 million of these people are chronic carriers. Each year more than half a million die as a result of acute or chronic HBV infection. Vaccination has been highly successful at preventing new HBV infections and has been implemented into the national immunization programs of more than 150 countries. However, the immune response to HBV vaccination varies greatly among individuals, with 5 to 10% of healthy adults failing to produce protective levels of antibodies. Several factors have been implicated in determining the response to HBV vaccination, including physical factors, such as age, gender, obesity, immunosuppression, and smoking, as well as variation in genes of the immune system (summary by Davila et al., 2010). [from OMIM]

Chronic form of hepatitis B infection. [from MONDO]

Virus diseases caused by the hepadnaviridae. [from MONDO]

Hepatitis that lasts for more than six months. [from HPO]

A chronic disorder of the liver in which liver tissue becomes scarred and is partially replaced by regenerative nodules and fibrotic tissue resulting in loss of liver function. [from HPO]

A viral infection caused by the hepatitis B virus. [from NCI]

Inflammation of the liver. [from HPO]