[Prolonged delta antigen in the blood without occurrence of anti-delta antibodies in 2 immunosuppressed patients].

: Delta coinfection or superinfection in a patient with chronic hepatitis B is characterized by a very transient delta antigenemia and an early seroconversion of IgM to IgG anti-delta. The persistent expression of delta antigen in the liver can be associated with acute, severe, or chronic hepatitis. In our two patients, delta antigenemia persisted respectively 10 weeks and 14 months with aggravation of liver histopathologic lesions without seroconversion. Such a serologic profile during delta infection does not seem to have been reported previously. These two cases concerned two patients with an important immunosuppression, one by a major immunosuppressive therapy and HIV superinfection, the other by an acquired immunodeficiency syndrome. The cytotoxic effect of delta virus in such circumstances is discussed.