245. Outcome Prediction - Proposal of a Risk Score in Anti-GBM Disease
Creators: name: Floyd1, Lauren
name: Kafagi2, Abdul Hadi
name: Brown3, Nina
name: Scott4, Jennifer
name: Reid2, Graeme
Publisher: name: Zenodo
Year: 2022
Subjects: Vasculitis
ANCA
Abstracts
Giant Cell Arthritis
MPA
GPA
EGPA
Takayasu
IgA vasculitis

description: <strong>Background:</strong> Anti-glomerular basement membrane (GBM) disease is a rare, aggressive vasculitis that typically presents with severe kidney dysfunction and pulmonary haemorrhage. The need for renal replacement therapy (RRT) at presentation is not uncommon and many patients go on to develop end stage kidney disease (ESKD). Clinical and histological variables predicting outcome are needed to individualise therapy and improve outcomes. <strong>Methods:</strong> A retrospective, multicentre, international cohort study collected data from 2005-2021. We investigated the Renal Risk Score (RRS) for its prognostic value in anti-GBM disease and modified its parameter to optimise outcome prediction. We used the published cut-offs for percentage of normal glomeruli, estimated glomerular filtration rate (eGFR), and a simplified cut-off for tubular atrophy and interstitial fibrosis (T0 ≤ mild to moderate, T1 = severe). We assigned points to each parameter and patients to risk groups as previously published. We then adjusted the eGFR cut-off according to patients’ outcome (G1 ≤ 7 ml/min/1.73 m<sup>2</sup>) and validated the modified RRS in anti-GBM disease. <strong>Results:</strong> Of the 137 patients included, median age was 60.5years (IQR 45-71) with a slight female predominance (n=74, 54%). Eighty-two patients (60%) presented with GBM antibodies, 37 (27%) presented with dual GBM and MPO antibodies, and 18 (13%) presented with GBM and PR3 antibodies. The median eGFR at presentation was 6ml/min (IQR 4.75-10) and 83.2% (n=114) required RRT at presentation. The RRS predicted renal survival in anti-GBM disease. None of the patients in the low risk group developed ESKD (n=8, ESKD=0, 0%), half of patients in the moderate risk group developed ESKD (n=26, ESKD=13, 50%), and over 70% of patients from the high risk group developed ESKD (n=91, ESKD=65, 72.2%, p&lt;0.0001), respectively. A regression tree with adapted risk points for patient outcomes further optimised outcome prediction (Figure 1, p&lt;0.0001). Seven of 16 patients in the low-risk group (43.8%), 47 of 58 patients in the moderate risk group (81%) and 49 of 51 patients in the high risk group (96.1%) required RRT at time of presentation (p&lt;0.0001). Four of these seven patients recovered renal function in the low risk group (57.2%), 15 of 47 patients in the moderate risk group (31.9%), and six of 49 patients in the high risk group, respectively (12.2%, p=0.008). None of the patients with the highest score of 11 recovered renal function. <strong>Conclusions</strong><strong>:</strong> Anti-GBM patients with as little kidney function as an eGFR of 2ml/min on presentation recovered kidney function. The renal risk score accurately predicted the need for renal replacement therapy at presentation, the potential for renal recovery and the development of ESKD. Combining histological features and clinical parameters enhances outcome prediction and utilising the score in clinical practice might aid management in the future. <strong>Disclosures:</strong> DG is a consultant to ChemoCentryx and Aurinia Inc. NB and SRB received honoraria from Vifor. The other authors have no other disclosures or competing interests.