Successful combination therapy of polyarteritis nodosa associated with a pre-core promoter mutant hepatitis B virus infection

Background/Aims: To describe the clinical and virological evolution of a polyarteritis nodosa (PAN) case associated with a hepatitis B virus (HBV) pre-core promoter mutant infection that was successfully treated with plasma exchanges, corticosteroids, and interferon alpha (IFN-α). Methods: Viral markers were used, including HBV DNA quantified by the branched DNA assay and detected by PCR, the HBV genome sequence, pre-S1Ag and anti-HBC IgM which were studied throughout the treatment period and the entire follow-up in the serum, while the presence of virus in extrahepatic sites was detected by immuno-staining. Results: The patient was infected with a typical pre-core promoter mutant harboring four point mutations. Pre-S1Ag was cleared rapidly from serum, most likely via the formation of immune complexes since HBV DNA declined more progressively. Viral infection was then cleared after a second episode of hepatocyte lysis. This was accompanied by a recovery from all clinical manifestations. Conclusions: The favorable treatment outcome observed in this first case of pre-core promoter HBV mutant associated PAN underlines that combination therapy based on IFN-α can clear pre-core promoter HBV infection and cure PAN. It also provides new insight in the pathogenesis of HBV associated PAN.