[Vasculitis 1998: new aspects in diagnosis and therapy]

Area of Science:

• Rheumatology and Immunology
• Nephrology

Background:

• The Chapel Hill conference updated systemic vasculitis classification.
• Standardized scoring systems (BVAS, VDI) for disease activity and organ damage are crucial.
• Differentiating bacterial infection from active vasculitis is clinically important.

Purpose of the Study:

• To review current understanding and diagnostic approaches for systemic vasculitides.
• To highlight the role of ANCA testing and serum procalcitonin in diagnosis and management.
• To discuss the pathogenesis and therapeutic strategies for ANCA-associated vasculitides.

Main Methods:

• Review of recent studies and clinical observations.
• Analysis of diagnostic markers including ANCA (C-ANCA/PR3-ANCA, P-ANCA/MPO-ANCA) and serum procalcitonin.
• Discussion of pathogenetic mechanisms involving neutrophils and T-cells.
• Overview of ongoing European therapeutic trials (EUVAS).

Main Results:

• Serum procalcitonin effectively differentiates active vasculitis from infection.
• ANCA testing demonstrates diagnostic reliability comparable to histology for vasculitis.
• ANCA positivity can occur in non-vasculitic conditions, requiring careful diagnosis.
• Association between ANCA and IgA nephropathy (IgA-GN) is noted, with differing clinical courses.

Conclusions:

• ANCA-positive vasculitides are likely T-cell mediated, with neutrophils expressing class II antigens and responding to infectious stimuli.
• Therapeutic strategies are evolving to optimize treatment, particularly limiting cyclophosphamide use to active disease stages.