학술논문
Lack of IgA Antineutrophil Cytoplasmic Antibodies in Henoch-Schönlein Purpura and IgA Nephropathy
Document Type
Article
Author
Source
Clinical Immunology and Immunopathology (Now Called Clinical Immunology); October 1994, Vol. 73 Issue: 1 p19-26, 8p
Subject
Language
ISSN
00901229; 10902341
Abstract
To verify whether IgA antineutrophil cytoplasmic antibody (ANCA) represents a serologic marker in Henoch-Schönlein purpura (HPS), we examined sera from 41 patients with the disease. Control sera from 28 patients with primary IgA nephropathy (IgA-N), 26 IgG-ANCA-positive vasculitis, and 28 normal controls were also studied. An increased IgA binding to neutrophil cytoplasmic extracts but not to purified ANCA antigens was found in 12.2-14.6% of HSP patients and in 14.3-21.4% of IgA-N patients versus 3.5% of normal controls. IgA binding to neutrophil cytoplasmic extracts correlated with serum IgA levels, IgA-rheumatoid factor, and IgA-fibronectin binding capacity. Moreover, low amounts of IgG and fibronectin were detected as contaminants in neutrophil cytoplasmic extracts and fibronectin could partly inhibit the binding of IgA to "crude" extracts. We conclude that IgA-ANCA are neither diagnostically nor immunologically specific in HSP and IgA-N. Several factors present in the sera of patients with IgA-related nephropathies seem to contribute to the "false-positive" IgA-ANCA demonstrable in these patients. Copyright 1994, 1999 Academic Press