AB1335 The clinicopathologic characteristics of granulomatosis with polyangiitis (wegener’s): Retrospective study of 45 patients in korea

Background The epidemiologic studies of granulomatosis with polyangiitis (Wegener’s) (GPA) have been reported primarily in European/American countries while there are only a few data available from Asian area. Recent clinical studies from Japan and China indicated that there is a geographical difference in the incidence of GPA (1, 2) and the different ANCA pattern between Asian and Caucasian may be associated with different clinical manifestations. Objectives The aim of this study is to anlayze the clinicopathologic characteristics of Korean patients with GPA. Methods We retrospectively reviewed 45 patients with GPA regarding clinical manifestations including histology, positivity of ANCA, categorization of disease stages, disease activity states in a single tertiary referral hospital. Patients were categorized into a predominant form based on immunopathologic scoring system of granulomatous-vasculitic activity (3). Results Thirty-one patients (68.9%) showed ANCA positivity (C-ANCA/P-ANCA, 44.4%/20.0%, proteinase-3 (PR3) ANCA/myeloperoxidase (MPO) ANCA, 48.4%/16.1%). ANCA positive patients (female 29.6%) were associated with higher frequency of renal involvement (51.6% vs 7.1%, p=0.004), elevated serum creatinine (29.0% vs 0%, p=0.018) and higher mortality (29% vs 7.1%, p=0.041) compared with ANCA negative patients. Thirty-three patients (73.3%, female 60.6%) were categorized into a granulomatous form, whereas vasculitic form and mixed form were found in 8.9% and 17.8% respectively. Age at diagnosis were younger (51.2 vs 62.3, p=0.045), and initial remission rate (69.7% vs 25.0%) and the relapse rate (60.8% vs 0%) were higher in granulomatous form compared with vasculitic form. Conclusions Taken together, in Korean patients with GPA, ANCA positivity was found in 68.9% and associated with renal involvement and higher mortality. The granulomatous form was predominant. References Fujimoto S, Watts RA, Kobayashi S, Suzuki K, Jayne DR, Scott DGet al. Comparison of the epidemiology of anti-neutrophil cytoplasmic antibody-associated vasculitis between Japan and the U.K. Rheumatology (Oxford).2011;50:1916-20. Chen M, Yu F, Zhang Y, Zou WZ, Zhao MH, Wang HY. Characteristics of Chinese patients with Wegener’s granulomatosis with anti-myeloperoxidase autoantibodies. Kidney Int. 2005; 68: 2225-29. Pierrot-Deseilligny Despujol C, Pouchot J, Pagnoux C, Coste J, Guillevin L. Predictors at diagnosis of a first Wegener’s granulomatosis relapse after obtaining complete remission. Rheumatol. 2010;49: 2181-90. Disclosure of Interest None Declared