The clinicopathological features and renal prognostic factors in pure membranous lupus nephritis-a large series cohort study from China.

BACKGROUND: Membranous lupus nephritis (MLN) is a subepithelial immune deposition or its morphological sequelae with or without mesangial changes. Previous studies on the prognosis of MLN have shown relatively small sample sizes and short follow-up periods. METHODS: Our study was a retrospective analysis of biopsy-proven MLN patients from January 2010 to January 2020 at Jinling Hospital in China. The clinical manifestations, pathological features, and renal outcomes of MLN patients were collected. The endpoint was defined as end-stage kidney disease (eGFR≤15 mL/min·1.73 m2 or need for renal replacement therapy) or a doubling of serum creatinine or an eGFR decline of more than 40%. We used Cox regression to analyze the risk factors for renal outcome and Kaplan-Meier curves were used to analyze renal survival rate. RESULTS: In the total of 2884 lupus patients, we screened 535 MLN patients. 456 MLN patients were recruited with an average age of 34 ± 12 years, 87.8% for female patients and 62.1% patients of nephrotic syndrome with proteinuria of 2.67 g/24h. After follow-up of 78 (IQR, 47.3-113.0) months, 37 (8.1%) patients reached the renal endpoint. The 5-year and 10-year renal survival rates were 95.8% and 89.4%, respectively. 370 patients (81.1%) achieved complete remission, 43 patients (9.4%) had partial remission, and only 43 had no response. 34.4% MLN experienced a relapse. The Cox regression showed the risk factors that affect the renal prognosis include male, hypertension history, anemia, high uric acid, acute kidney injury, and interstitial fibrosis in the renal pathology. CONCLUSIONS: MLN mostly manifested as nephrotic syndrome, with few renal dysfunctions. Although MLN had a high relapse rate, most patients had a response to immunosuppressants and had a good renal outcome.

Prediction of treatment response in lupus nephritis using density of tubulointerstitial macrophage infiltration.

Background: Lupus nephritis (LN) is a common disease with diverse clinical and pathological manifestations. A major challenge in the management of LN is the inability to predict its treatment response at an early stage. The objective of this study was to determine whether the density of tubulointerstitial macrophage infiltration can be used to predict treatment response in LN and whether its addition to clinicopathological data at the time of biopsy would improve risk prediction. Methods: In this retrospective cohort study, 430 patients with LN in our hospital from January 2010 to December 2017 were included. We used immunohistochemistry to show macrophage and lymphocyte infiltration in their biopsy specimens, followed by quantification of the infiltration density. The outcome was the treatment response, defined as complete or partial remission at 12 months of immunosuppression. Results: The infiltration of CD68+ macrophages in the interstitium increased in patients with LN. High levels of CD68+ macrophage infiltration in the interstitium were associated with a low probability of treatment response in the adjusted analysis, and verse vice. The density of CD68+ macrophage infiltration in the interstitium alone predicted the response to immunosuppression (area under the curve [AUC], 0.70; 95% CI, 0.63 to 0.76). The addition of CD68+cells/interstitial field to the pathological and clinical data at biopsy in the prediction model resulted in an increased AUC of 0.78 (95% CI, 0.73 to 0.84). Conclusion: The density of tubulointerstitial macrophage infiltration is an independent predictor for treatment response in LN. Adding tubulointerstitial macrophage infiltration density to clinicopathological data at the time of biopsy significantly improves risk prediction of treatment response in LN patients.