[Clinical study on five myeloperoxidase specific anti-neutrophil cytoplasmic antibody (MPO-ANCA) positive Churg-Strauss syndrome cases].

OBJECTIVE: In order to clarify the clinical characteristics of ANCA positive Churg-Strauss syndrome (CSS), ten CSS patients were analyzed.

METHODS: ANCA was detected using an immunofluorescence (IF) assay and ELISA. ANCA was measured in both active and inactive stage of the disease.

RESULTS: ANCA was present in 5 patients (5/10 : 50%) with active CSS phase and all ANCA patient results showed perinuclear pattern by IF assay and myeloperoxidase specific results by ELISA. Patients with ANCA were older (average age : 58.0) and had higher incidence of renal involvement (4/5 : 80%) than was found with ANCA negative patients (average age; 38.4, no patients with renal involvements). Among 5 patients with ANCA, one had rapidly progressive glomerulonephritis and one had alveolar hemorrhage. Remission was induced for 4 ANCA positive patients by corticosteroid and/or immunosuppressive drug and one required long term maintenance hemodialysis. ANCA titer changed in parallel with disease activity, such as proteinuria, hematuria and alveolar hemorrhage. No significant differences in regard to eosinophilia, serum IgE and CRP titer were found between ANCA positive and negative patients.

CONCLUSION: These results strongly indicate that MPO-ANCA may play an important role in the pathogenesis of vascultis, such as renal injury and alveolar hemorrhage in CSS.