[Viral B reactivation: Risk factors and prevention]

The viral B reactivation is associated to deadly serious forms. There exist populations suffering this risk yet with a possibility of prevention through a pre-emptive treatment.

Establishing the diagnosis of a viral B reactivation. Identifying the patients with risk of exposure to viral B reactivation and implementing the means of prevention of viral reactivation.

literature review

the diagnosis of reactivation is not consensual. It is evoked facing a fast increase of aminotransferases with the ALAT superior to 5-10 times normal or superior to 3 times the basic value, an ascension of the HBV DNA within the serum, a reappearance of anti Hbc of IgM type with, most often, a weak title and /or a reversion Hbs. The reactivation depends on the type of treatment and of the viral B status. It was described under chemotherapy concerning the solid tumors particularly that of the breast, in haematology and increases with the resort to monoclonal antibody (anti-CD20). Under anti-TNFα a reactivation is possible within a variable deadline from the 1st to the 12th perfusion. Besides the type of treatment, the risk is more important with the patients Ag Hbs positive and correlated with the viremia. However, the patients having an occult hepatitis B or even a recovered from hepatitis are equally exposed to the risk of reactivation.

viral reactivation is frequent since the larger use of immunosuppressive therapy, anti-TNFα and monoclonal antibody. The determination of the initial viral B status by a serology is indispensable. In order to indicate either surveillance or a preemptive treatment.