P0209PRESENTATION AND OUTCOMES OF ANCA ASSOCIATED VASCULITIS: THE SCOTTISH EXPERIENCE

Background and Aims This is a national project undertaken on behalf of the Scottish Renal Biopsy Registry describing the presentation, biopsy appearances, management and outcomes of patients presenting with a new diagnosis of renal biopsy proven ANCA associated vasculitis (AAV) to all units in Scotland. Method The Scottish Renal Biopsy Registry collects data annually on all renal biopsies performed across Scotland. From the Registry, all patients with a possible diagnosis of AAV found on renal biopsy performed between1/1/2014 and 31/12/2017 were identified. Individual units searched the electronic patient records of each patient and identified all those with a new diagnosis of AAV. Those undergoing repeat biopsy or who were not felt to have AAV on biopsy were excluded. Demographic data including immunological and outcome data were recorded and statistical analysis was undertaken in SPSS (v22). Results 267 patients were identified as having AAV across 8 centres and followed up for an average of 989 (IQR 610-1247) days. In 52% (n= 140) the biopsy indication was acute kidney injury. 38% (n=101) had a diagnosis of granulomatosis with polyangiitis (GPA). 52% (n=140) were female and the mean age at biopsy was 66.6±12.1 years. 38% (n=100) were PR3 positive. The average number of glomeruli on biopsy was 14 (IQR 11-21) with 3 (IQR 2-7 crescents. 28% (IQR 7-51) of viable glomeruli contained crescents. 41% (n=110) had at more than 10% interstitial fibrosis on biopsy. Creatinine at biopsy was 208µmol/L (IQR 141-380 µmol/L) and at 90 days 141 µmol/L (IQR 101-222 µmol/L). Most patients received standard induction therapy of cyclophosphamide and steroid. 24% (n=65) had plasma exchange at presentation and 11% (n=30) renal replacement therapy (RRT). 15% (n=39) patients relapsed with an average time to relapse of 511 (IQR 223-11127) days. 62% (n=24) of relapses were treated with rituximab. Those with GPA relapsed earlier. 12% (n= 31) developed end stage renal disease (ESRD). 18% (n=49) died with 14 patients (5%) dying within 90 days of biopsy. Average time to death was 246 (IQR 89-321) days. There was a trend towards an increased risk of death with those who developed ESRD. Patients who received PEX or RRT during initial admission were no more likely to relapse or die than those who did not. Conclusion This study accurately describes the presentation, management and outcomes of patients with AAV and renal involvement in Scotland. This allows comparison between centres within Scotland and other countries. The cohort will added to and followed to look at longer term outcomes.