250. Combined crescentic and chronicity score for prognostic assessment in ANCA-associated vasculitis with glomerulonephritis
Creators: name: Moura1, Marta Casal
name: Fervenza2, Fernando C.
name: Specks1, Ulrich
name: Sethi3, Sanjeev
Publisher: name: Zenodo
Year: 2022
Subjects: Vasculitis
ANCA
Abstracts
Giant Cell Arthritis
MPA
GPA
EGPA
Takayasu
IgA vasculitis

description: <strong>Background:</strong> Combining the evaluation of acute inflammatory activity and chronic changes on kidney biopsy is probably optimal for prognostic assessment of renal outcomes in antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) with glomerulonephritis (AAV-GN). <strong>Methods:</strong> A retrospective cohort study of MPO- or PR3-ANCA positive patients with AAV and active renal disease. We developed a Crescentic Index (CI) corresponding to the ratio between the number of crescents and/or necrosis and the total number of glomeruli and scored as follows: 0 ≤ 25%, 1 = 26-50% and 2 &gt; 50%. Then, we summed the score obtained in the CI combined with the grades obtained in the Mayo Clinic Chronicity Score (MCCS) (1 – minimal, 2 – mild, 3 – moderate and 4 – severe) to evaluate the implications on outcome prediction in AAV-GN. <strong>Results:</strong> We analyzed 326 patients with kidney biopsies available to score. The biopsies had in median (IQR), 13 glomeruli (9-20), 4 crescents (2-6) and a CI of 28.6% (15.3-47.6). We applied the CI and found that 154 (47.2%) patients scored 0, 106 (32.5%) patients scored 1 and 66 (20.2%) scored 2. After the combination of the scores, the population was classified according with the risk of progression to kidney failure (KF) in 3 classes as (i) low – 134 (41.1%), (ii) intermediate – 125 (44.8%), and (iii) high – 46 (14.1%). Median eGFR at baseline correlated with the overall risk categories: 40.6 vs. 20.8 vs. 16.2 mL/min/1.73 m<sup>2</sup>, p&lt;0.0001. The proportion of patients with severe renal disease at diagnosis was increased in patients classified as high: 89.1% vs. 71.2% vs. 37.3%, p&lt;0.0001. Clinical presentation, severity of the disease estimated by BVAS/WG, ANCA specificity, remission-induction or remission-maintenance treatment did not differ across the 3 categories. Renal recovery was more frequent in patients at low risk of progression: 87.1% vs. 56.3% vs. 36.7%, p&lt;0.0001, whereas kidney failure at 12 months, dialysis, and combined events of KF and/or death at 24 months were more frequent in patients at higher risk (41.3 % vs. 15.8% vs. 4.5%, p&lt;0.0001; 35.7% vs. 12.6.0% vs. 6.0%, p&lt;0.001; 47.8% vs. 21.9% vs. 10.4%, p&lt;0.0001, respectively). The combination of CI with MCCS grades independently predicted the risk of KF at 12 months (HR 2.107,95%CI 1.388-3.199, p&lt;0.0001), particularly increased in patients classified as high risk (HR4.237, 95%CI 1.837-9.774, p=0.001) and in patients with PR3-ANCA (HR1.897, 95%CI 1.072-3.358, p=0.028) independently of eGFR at AAV-GN diagnosis and adjusted for severity of renal involvement and age. <strong>Conclusions:</strong> The combined assessment of acute inflammatory activity and chronic changes on kidney histology independently predicted renal outcomes in patients with AAV-GN. The combined score is simple to apply and accurately stratifies the patients according in 3 categories of risk for kidney failure. <strong>Disclosures:</strong> Dr. U. Specks has received consulting fees from AstraZeneca, ChemoCentryx and research grants from AstraZeneca, GSK, Bristol Myers Squibb, Genentech. Dr. F.C. Fervenza has received research grants from Roche/Genentech.