Bullous pemphigoid in an HB virus carrier: interaction between corticosteroids and HB virus

A case of bullous pemphigoid (BP) in a 47-year-old female hepatitis B virus (HBV) carrier is reported. Disseminated bullae covered the patient's entire body including the hands and feet. BP was diagnosed on the basis of pathological and immunological observations examining immunofluorescence and cross reactions to both bullous pemphigoid antigen (BPAG) 1 and BPAG 2. Although oral prednisolone (80 mg daily) rapidly healed the eruption, liver function failed to respond, resulting in the patient's death. This liver dysfunction was attributed to the HBV infection. Use of the polymerase chain reaction showed that HBV in this case had transformed into its precore mutation form during the therapy. Standard tests on first examination did not detect HBV in this patient, but later detailed analysis suggested that she had been an HBV carrier since birth. Such carriers sometimes test negative for HBs antigen, when only a little HBV is present in the liver. Great care should also be exercised when using high doses of corticosteroids to treat bullous diseases in HBV carriers, because these drugs may aggravate HBV infections and cause liver failure.