Natural history of chronic hepatitis B:Phases in a complex relationship
摘要
Chronic hepatitis B(CHB)is a condition of globalprevalence and its sequelae include cirrhosis and hepatocellular carcinoma.The natural history of CHB isa complex interplay of virological,environmental andhost factors.The dynamic relationship between thevirus and host evolves over the duration of the infection and different phases of the disease have been observed and described.These have been conceptualizedin terms of the state of balance between the host immune system and the hepatitis B virus and have beengiven the labels immune tolerant,immune clearance,immune control and immune escape although othernomenclature is also used.Host factors,such as age atinfection,determine progression to chronicity.Virological factors including hepatitis B viral load,mutationsand genotype also have an impact on the adverseoutcomes of the infection,as do hepatotoxic cofactorssuch as alcohol.Our understanding of the natural history of CHB has evolved significantly over the past fewdecades and characterizing the phase of disease ofCHB remains an integral part of managing this virus in the clinic.