Analysis of the clinical characteristics of different serotypes of patients with anti-neutrophil cytoplasm antibody-associated vasculitis

Objective This study was aimed to analyze the difference in the clinical features of pa-tients with anti-proteinase-3 anti-neutrophil cytoplasm antibody (PR3-ANCA) and anti-myeloperoxidase (MPO)-ANCA associated vasculitis (AAV); and to discuss the risk factor of relapse. Methods We retrospectively analyzed 103 AAV patients who were diagnosed in Tianjin Medical University General Hospital from January 2010 to May 2016. Based on ANCA serotypes, patients were divided into PR3-ANCA positive, MPO-ANCA positive, both PR3-ANCA and MPO-ANCA negative groups. The difference between the PR3-ANCA and MPO-ANCA groups was analyzed The χ2 test and t-test were used for statistical analysis. The Logistic regression analysis was used to evaluate the risk factors of relapse in AAV patients. Results This study included 103 cases of AAV patients, in which, 79(76.7%) patients were with MPO-ANCA and 23(22.3%) were PR3-ANCA. The MPO-ANCA group had more coronary heart disease than PR3-ANCA group (χ2=10.36, P= 0.001). The MPO-ANCA group had more pulmonary fibrosis than PR3-ANCA group (χ2=12.08, P=0.001). Logistic regres-sion analysis showed that the risk factors of relapse was increase of erythrocyte sedimentation rate (ESR) [OR(95%CI)=9.20 (1.06, 79.98), P=0.04]. Conclusion AAV patients with positive MPO-ANCA and PR3-ANCA are different. Key words: Anti-neutrophil cytoplasm antibody; Vasculitis; Serotype; Renal involvement; Relapse