Hepatitis B virus-associated
polyarteritis nodosa (HBV-PAN) is a typical form of classic PAN whose pathogenesis has been attributed to
immune-complex deposition with
antigen excess. We conducted the current study to 1) analyze the frequency of HBV
infection in patients with PAN, in light of the classification systems described since 1990; 2) describe the clinical characteristics of HBV-PAN; 3) compare the evolution according to conventional or
antiviral treatment; and 4) evaluate long-term outcome. One hundred fifteen patients were included in therapeutic trials organized by the French
Vasculitis Study Group and/or referred to our department for HBV-PAN between 1972 and 2002. To determine the frequency of HBV-PAN during the 30-year period, we analyzed a control group of patients with PAN without HBV
infection, followed during the same period and diagnosed on the same bases. Depending on the year of diagnosis, different treatments were prescribed. Before the
antiviral strategy was established, some patients were given
corticosteroids (CS) with or without
cyclophosphamide (CY). Since 1983, treatment for patients with HBV markers has combined 2 weeks of CS followed by an
antiviral agent (successively,
vidarabine,
interferon-alpha, and
lamivudine) combined with
plasma exchanges (PE).Ninety-three (80.9%) patients entered remission during this period and 9 (9.7%) of them relapsed; 41 (35.7%) patients died. For the 80 patients given the
antiviral strategy as intention-to-treat, 4 (5%) relapsed and 24 (30%) died vs 5 (14.3%) relapses (not significant [NS]) and 17 (48.6%) deaths (NS) among the 35 patients treated with CS alone or with CY or PE. HBe-anti-HBe seroconversion rates for the 2 groups, respectively, were: 49.3% vs 14.7% (p < 0.001). Patients who seroconverted obtained complete remission and did not relapse.Thus, HBV-PAN, a typical form of classic PAN, can be characterized as follows: when renal involvement is present, so is renal
vasculitis;
glomerulonephritis due to
vasculitis is never found;
antineutrophil cytoplasmic antibodies (
ANCA) are not detected; relapses are rare, and never occur once viral replication has stopped and seroconversion has been obtained. Combining an
antiviral drug with PE facilitates seroconversion and prevents the development of long-term hepatic complications of HBV
infection. The major cause of death is gastrointestinal tract involvement. Importantly, the frequency of HBV-PAN has decreased in relation to improved blood safety and vaccination campaigns.