FRI0274 Morfological indexes in lupus nephritis – do they have prognostic value?
Authors: D Navarro, AC Ferreira, H Viana, F Carvalho, F Nolasco
Journal: Annals of the Rheumatic Diseases (2017)

<h3>Background</h3> Lupus nephritis (LN) is a serious complication of systemic lupus erythematosus (SLE). With current therapies, a high remission rate is observed, this being the most important prognostic factor. Currently, therapy is guided by findings in the renal biopsy, following the ISN/RPS classification. Although recommended by EULAR, Austin and Hill9s morphological indexes are not routinely obtained. <h3>Objectives</h3> To analyze the importance and applicability of the different morphological indexes in predicting response to treatment and prognosis. <h3>Methods</h3> Retrospective single center study of consecutive SLE and biopsy proven LN patients, diagnosed from 2010 to 2016. We evaluated the following outcomes: clinical remission, renal function and proteinuria at end of follow-up (FUP) (g/24h). Complete remission was defined as a reduction of proteinuria to &lt;0,5g/24h, inactive urinary sediment and serum creatinine &lt;115% of baseline; partial remission same parameters, except proteinuria &lt;1g/24h if initial value &lt;3h/24h, or reduction to &lt;3g/24h if initial value &gt;3g/24h. The studied predictors were the INS/RPS LN classification and the morphological indexes described by Austin (Activity and Chronicity) and Hill, obtained after histomorphological review of renal biopsies. Statistical analysis was performed with STATA software. <h3>Results</h3> During 6 years, there were 46 biopsy-proven LN cases, 84,8% (n=39) woman, median 35 years old (27 – 42,5) and 57,6% (n=19) caucasian. 39 patients were already known to have SLE, 7,44 (1,13 – 12,3) years previously. The median FUP was 31,9 (13,2 – 45,6) months. Based on biopsy findings, 35 patients were started on immunosuppression – induction in 50% of cases with MMF and in 50% with cyclophosphamide; maintenance in 81% with MMF, the remaining with azathioprine. Complete remission was achieved in 58% of patients, 27% achieving partial remission. We observed 4 LN relapses. 96% (n=44) of the patients survived at the end of FUP, with a median serum creatinine of 0,8 mg/dl (0,7 – 0,99), eGFR 99,8 ml/min (71,2 – 116,8) and proteinuria of 0,6 g/24h (0,2 – 1,6). We observed that Class IV patients had, at presentation, lower eGFR (67,3 vs 94,6 ml/min; p=0,02), higher proteinuria (4,26 vs 2,37; p=0,02) and a tendency towards higher C3 consumption (58,9 vs 77,4; p=0,06). We did not observe correlations between ISN/RNP Classification and the outcomes at the end of FUP. The correlations between clinical findings and morphological indexes (Hill and Austin) are summarized in table 1: Both the Hill biopsy index and the Chronicity index were correlated with renal function and proteinuria at the end of FUP. The Activity index correlated with the immunological findings – C3, C4 and anti-dsDNA. <h3>Conclusions</h3> EULAR guidelines suggest that histomorphological evaluation in LN should go beyond ISN/RNP classification, and our data supports that – we observed a correlation between the renal outcomes and the indexes described by Austin and Hill. <h3>Disclosure of Interest</h3> None declared