Mo318end-Stage Renal Disease Related Factors in Anca-Associated Vasculitis

Abstract

Background and Aims Management of ANCA-Associated Vasculitis (AAV) is in constant update. The aim of the study is to describe our experience as a territorial reference center with this systemic disease and to analyze which factors have a significant influence on the development of end-stage renal disease (ESRD). Method Retrospective observational study. All the patients who developed AAV in our center between 2010 and 2019 were included. Demographic variables (age, sex), renal function, other vasculitis related symptoms, induction and maintenance therapy, response degree and follow-up were collected. Categorical variables are expressed as percentages and compared using Chi2 test. Quantitative variables are expressed as mean ± standard deviation and compared using Mann-Whitney U test. Cox regression was performed to determine independent predictors of ESRD. Kaplan-Meier was used to estimate ESRD-free survival. Statistical significance for a value of p< 0,05. Statistical analysis was performed with SPSS 25.0. Results 45 patients were analyzed, with an average age of 70 ± 11 years. 62.2% were men. Mean time of follow-up 36 ± 31.6 months. 37.8% presented c-ANCA autoantibodies and 57.8% p-ANCA. Mean baseline serum creatinine level was 5.51 ± 3.65 mg/dl and proteinuria 2.82 ± 2.48 g/24h. 77.8% received cyclophosphamide as induction immunosuppressive treatment whereas 13.3% rituximab. 50% received azathioprine, 36.1% mycophenolate and 13.9% rituximab as maintenance treatment. 37.8% patients underwent plasma exchange therapy and 44.4% hemodialysis. Complete remission was achieved by 13.3% of patients, while 57.8% partial remission. 28.9% had absence of remission. 28.9% achieved ESRD. ESRD was associated with undergoing hemodialysis (69.2% vs 30.8% p=0.033), to the type of response (complete 7.7% vs partial 23.1% vs no response 69.2%), baseline creatinine level (8.36 ± 5.44 vs 4.35 ± 1.64 mg/dl p=0.011), creatinine 6 months after induction treatment (4.3 ± 2.05 vs 2.04 ± 0.77 mg/dl p=0.001) and at the end of follow-up (6.33 ± 2.47 mg/dl vs 2.2 ± 1.29 mg/dl p=0.001) and also to baseline proteinuria (4.21 ± 3.12 vs 2.25 ± 1.96 p=0.003), proteinuria 6 months after induction treatment (1.4 ± 1.46 vs 0.58 ± 0.73 g/24h p=0.014) and at the end of follow-up (2.48 ± 1.9 vs 1.12 ± 1.64 p=0.001). Logistic regression only showed end of follow up serum creatinine level as an independent risk factor of ESRD (OR3.74 IC 95% 1.01-13.75 p=0.047). ESRD-free survival chance after 5 of follow-up was 67%. Conclusion Only serum creatinine level at the end of follow-up could be found as an associated factor with ESRD. Greater number of patients would be needed in order to obtain other factors leading to ESRD in patients with AAV.