Morphological Indexes: Can They Predict Lupus Nephritis Outcomes? A Retrospective Study

• Autor(a) principal: Navarro, D
• Data de Publicação: 2019
• Outros Autores: Ferreira, AC, Viana, H, Carvalho, F, Nolasco, F
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.17/3339
• topic: HCC NEF; Biopsy; Analysis of Variance; Complement C3/metabolism; Glomerular Filtration Rate; Follow-Up Studies; Prognosis; Immunosuppressive Agents/therapeutic use; Kidney/pathology; Kidney/physiopathology; Lupus Erythematosus, Systemic/complications; Lupus Nephritis/classification; Lupus Nephritis/pathology; Lupus Nephritis/physiopathology; Lupus Nephritis/therapy; Proteinuria/diagnosis; Proteinuria/epidemiology; Remission Induction; Retrospective Studies; Treatment Outcome

INTRODUCTION: Lupus nephritis is a serious complication of systemic lupus erythematosus. Currently, therapy is guided by findings in the renal biopsy, following the International Society of Nephrology / Renal Pathology Society classification. Austin and Hill's histomorphological indexes are not routinely obtained. In this retrospective single-centre study, we aimed to analyze the importance and applicability of the different morphological indexes in predicting response to treatment and prognosis. MATERIAL AND METHODS: Patients with kidney biopsy demonstrating lupus nephritis from the 2010 - 2016 period were included. We analyzed their demographic data, comorbidities, clinical presentation and laboratorial evaluation at the time of renal biopsy. We evaluated the following outcomes: clinical remission, renal function and proteinuria at end of follow-up. Histologic analysis was performed using the International Society of Nephrology / Renal Pathology Society classification and the morphological indexes described by Austin (Activity and Chronicity) and Hill. Univariate and multivariate statistical analysis was performed using STATA software. RESULTS: We analyzed 46 biopsy-proven lupus nephritis cases, with a median follow-up of 31.9 (13.2 - 45.6) months. Based on biopsy findings, 35 patients were started on immunosuppressive therapy. We observed that Class IV patients had, at presentation, lower estimated glomerular filtration rate (67.3 vs 94.6 mL/min; p = 0.02), higher proteinuria (4.26 vs 2.37 g/24 hours; p = 0.02) and a non-significantly higher C3 consumption (58.9 vs 77.4 mg/dL; p = 0.06). We did not observe correlations between International Society of Nephrology / Renal Pathology Society classification and the outcomes at the end of follow-up. In contrast, both the Hill biopsy index and Austin's Chronicity index were correlated with renal function and proteinuria at the end of follow-up. Austin's Activity index correlated with the immunological findings (C3, C4 and anti-dsDNA) at presentation. DISCUSSION: Because clinical activity poorly correlates with histologic activity, histological findings are fundamental when assessing patients with suspected lupus nephritis. The most recent International Society of Nephrology / Renal Pathology Society report supports the European League Against Rheumatism guidelines, encouraging the adoption of histomorphological indexes when evaluating lupus nephritis. Our data, showing a correlation between the renal outcomes and the indexes described by Austin and Hill, supports this view. CONCLUSION: The histomorphological indexes in lupus nephritis are easily obtainable, can predict renal outcomes and may help in the management of such patients.