Retrospective Observational Study to Define HBsAg Loss With or Without Seroconversion to antiHBs in Patients With Chronic Hepatitis by B Virus Treated With Nucleoside/Nucleotide Analogs

Retrospective Observational Study to Define HBsAg Loss With or Without Seroconversion to antiHBs in Patients With Chronic Hepatitis by B Virus Treated With Nucleoside/Nucleotide Analogs

Define the patients who lost HBsAg, studying the loss predictive factors and if there was suspension of treatment, study the evolution after that

Inclusion Criteria:

• >18 years old
• Chronic hepatitis B (HBeAg+ or HBeAg-)
• HBsAg loss
• Treated with nucleoside/nucleotide analogues
• With or without previous interferon (IFN/PEG-IFN)
• Patients with HBsAg loss after 2006
• Immunocompetent patients

Exclusion Criteria:

• Spontaneous HBsAg loss
• HBsAg loss while treatment in monotherapy or combinated with IFN or PEG-IFN.
• Patients with hepatitis delta virus (HDV) coinfection.
• Patients with hepatitis C virus (HCV) coinfection.
• Patients with HIV coinfection.
• Patients with liver transplant.
• Patients with reactivated hepatitis B virus (HBV) by immuno-suppressive treatment.