UNLABELLED: From 1987 to 1991, 2500 sera were tested for presence of anti-neutrophil cytoplasmic antibodies (ANCA) by standard indirect immunofluorescence (IIF) and specific proteinase 3 (PR3) and myeloperoxydase (MPO) ELISA. Clinical and histological data leading to precise diagnosis were retrospectively obtained in 98 patients with ANCA positivity by IIF and then a comparative study based on ANCA specificity was performed. Vasculitis was present in all cases. Among patients with anti-PR3 (n = 38), 19 had Wegener's granulomatosis (WG), 15 microscopic polyarteritis (mPA), 2 idiopathic necrotizing and crescentic glomerulonephritis (NCGN) and 2 relapsing polychondritis (RP). Among patients with anti-MPO (n = 45), 26 had mPA, 3 classical polyarteritis nodosa (PAN), 5 WG, 8 NCGN, 2 systemic lupus erythematosus (SLE) and one Churg-Strauss syndrome (CSS). Negative MPO and PR3 specific ELISA despite positive IIF were observed in 15 patients (13 WG, 1 mPA, 1 PAN). In the PR3 group, males predominated (66%) and the mean age was 49 years (range 13-85); in the MPO group, females predominated (62%) and the mean age was 57 years (range 13-85). These differences were statistically significant (p < 0.05). Renal involvement was present in 92% of patients and renal biopsy showed pauci-immune necrotizing and crescentic glomerulonephritis in nearly all cases. PR3 specificity was associated with frequent eye involvement (32%) and presence of granulomas (45%), but was not associated with other autoantibodies. MPO specificity was associated with a higher prevalence of pulmonary hemorrhage (40%) and various autoimmune disorders, especially antinuclear antibodies. Cholestasis was observed in 50% of WG with negative MPO and PR3 ELISA. Renal and patient survival at the 75th percentile was 15 months with MPO-ANCA and 16 months with PR3, and was similar for patients with WG and mPA. Relapses occurred in 20% of patients with anti-MPO and 36% of patients with anti-PR3. Serological follow-up was obtained in 44 patients. With immunosuppressive treatment, ANCA disappeared in 66% of cases and this disappearance was always associated with absence of disease activity. IN CONCLUSION: 1. This study confirms that the presence of ANCA is a good marker of vasculitis. 2. Despite some clinical differences, MPO and PR3-associated vasculitis have a similar prognosis. 3. The titer of ANCA determined by ELISA is not correlated with the severity of vasculitis but disappearance of ANCA is always associated with absence of disease activity.
UNLABELLED: From 1987 to 1991, 2500 sera were tested for presence of anti-neutrophil cytoplasmic antibodies (ANCA) by standard indirect immunofluorescence (IIF) and specific proteinase 3 (PR3) and myeloperoxydase (MPO) ELISA. Clinical and histological data leading to precise diagnosis were retrospectively obtained in 98 patients with ANCA positivity by IIF and then a comparative study based on ANCA specificity was performed. Vasculitis was present in all cases. Among patients with anti-PR3 (n = 38), 19 had Wegener's granulomatosis (WG), 15 microscopic polyarteritis (mPA), 2 idiopathic necrotizing and crescentic glomerulonephritis (NCGN) and 2 relapsing polychondritis (RP). Among patients with anti-MPO (n = 45), 26 had mPA, 3 classical polyarteritis nodosa (PAN), 5 WG, 8 NCGN, 2 systemic lupus erythematosus (SLE) and one Churg-Strauss syndrome (CSS). Negative MPO and PR3 specific ELISA despite positive IIF were observed in 15 patients (13 WG, 1 mPA, 1 PAN). In the PR3 group, males predominated (66%) and the mean age was 49 years (range 13-85); in the MPO group, females predominated (62%) and the mean age was 57 years (range 13-85). These differences were statistically significant (p < 0.05). Renal involvement was present in 92% of patients and renal biopsy showed pauci-immune necrotizing and crescentic glomerulonephritis in nearly all cases. PR3 specificity was associated with frequent eye involvement (32%) and presence of granulomas (45%), but was not associated with other autoantibodies. MPO specificity was associated with a higher prevalence of pulmonary hemorrhage (40%) and various autoimmune disorders, especially antinuclear antibodies. Cholestasis was observed in 50% of WG with negative MPO and PR3 ELISA. Renal and patient survival at the 75th percentile was 15 months with MPO-ANCA and 16 months with PR3, and was similar for patients with WG and mPA. Relapses occurred in 20% of patients with anti-MPO and 36% of patients with anti-PR3. Serological follow-up was obtained in 44 patients. With immunosuppressive treatment, ANCA disappeared in 66% of cases and this disappearance was always associated with absence of disease activity. IN CONCLUSION: 1. This study confirms that the presence of ANCA is a good marker of vasculitis. 2. Despite some clinical differences, MPO and PR3-associated vasculitis have a similar prognosis. 3. The titer of ANCA determined by ELISA is not correlated with the severity of vasculitis but disappearance of ANCA is always associated with absence of disease activity.
Authors: Sophia Lionaki; Elizabeth R Blyth; Susan L Hogan; Yichun Hu; Brent A Senior; Caroline E Jennette; Patrick H Nachman; J Charles Jennette; Ronald J Falk Journal: Arthritis Rheum Date: 2012-10