GB virus C in systemic medium- and small-vessel necrotizing vasculitides.

Background: Vasculitides are diseases of unknown origin in the majority of cases, but sometimes are the consequence of viral infections; for instance, hepatitis B virus (HBV)-related polyarteritis nodosa (PAN) or hepatitis C virus (HCV)-associated cryoglobulinaemia.

Objective: To investigate the role of hepatitis G or GB virus C (GBV-C) in various forms of medium- and small-vessel vasculitides.

Design: Retrospective analyses of sera.

Setting: Tertiary care hospital in Bobigny, France.

Patients: Fifty-six vasculitides: 19 HBV-PAN, 10 PAN without HBV infection, 11 microscopic polyangiitis (MPA), seven Churg-Strauss syndrome (CSS) and nine Wegener's granulomatosis (WG). Every sample was collected before treatment.

Measurements: GBV-C RNA was detected using a reverse transcription-polymerase chain reaction assay with primers derived from the conserved GBV-C helicase and NS5a regions.

Results: GBV-C was detected in five of the 56 samples (8.9%): four patients with HBV-related PAN and one with MPA; three of these patients (two with HBV-PAN, one with MPA) had been transfused and two HBV-PAN were i.v. drug addicts. GBV-C was not found in CSS or in WG.

Conclusion: GBV-C infection was observed only in patients who had been transfused or who were addicts. This virus is unlikely to have a primary role in vasculitides.