Antineutrophil Cytoplasmic Antibody in Korean Children with Henoch-Schonlein Purpura

ABSTRACT

PURPOSE: There have been some reports on the prevalence of positive antineutrophil cytoplasmic antibody(ANCA) in Henoch-Schonlein purpura(HSP), but the results were conflicting. We performed this study to evaluate the clinical significance of ANCA(c-ANCA and p-ANCA) in Korean children with HSP. METHODS: The medical records of 30 patients(13 boys and 17 girls) aged 6.0+/-1.9(5-12) years with a clinical diagnosis of HSP based on the EULAR/PReS criteria were reviewed retrospectively. From the years 2007 to 2008, the sera from children with acute HSP were tested for antineutrophil cytoplasmic antibodies(ANCA). The target antigens of these autoantibodies are proteinase 3(c-ANCA) or myeloperoxidase(p-ANCA). RESULTS: Palpable purpura was seen in all 30 patients(100%), abdominal pain in 20(67%), arthralgia in 17(57%), and renal involvement in 11(37%). Laboratory findings showed leukocytosis in 4 patients(13%), thrombocytosis 18 in(60%), and elevated erythrocyte sedimentation rate in 18(60%). Anti-streptolysin O titers were elevated in 7% of the patients and no patient showed elevation of serum IgA level. The sera from 29 patients were negative for c-ANCA and p-ANCA by indirect immunofluorescence, but only one patient had weakly positive results, which became negative at follow-up. CONCLUSION: We conclude that c-ANCA or p-ANCA is not an important serologic marker in children with HSP, because it was neither diagnostically nor immunologically specific in children with HSP. These results suggest that ANCA are not involved in the pathogenesis of HSP in children.