Usefulness of ISN/RPS classification of lupus nephritis

Treatment outcome and survival status among adult patients treated for lupus nephritis in selected tertiary hospitals of Ethiopia

Lupus nephritis (LN) is kidney involvement of systematic lupus erythematous that ranges from mild to severe and occurs in 60% of adult patients. Despite advances in therapy, LN morbidity and mortality remains high. There is a paucity of data regarding adult LN patient's treatment outcome, survival status, and associated factors in developing countries, particularly in Ethiopia. This study aimed to assess the treatment outcome, survival status, and associated factors of adult patients treated for LN in two selected tertiary hospitals [Tikur Anbessa Specialized Hospital (TASH) and St. Paul's Hospital Millennium Medical College (SPHMMC)] of Addis Ababa, Ethiopia. A hospital-based retrospective cross-sectional multicenter study was conducted from January 1, 2016 to January 1, 2021. Socio-demographic, clinical, and treatment-related data were collected from patient's medical records by using a structured abstraction checklist. Descriptive statistics were used to summarize the quantitative data as appropriate. The modified Aspreva Lupus Management Study (mALMS) criteria was applied to categorize LN treatment outcomes into complete, partial, and non-response. Multinomial logistic regression analysis was performed to identify predictors of LN treatment outcome. Patients' survival was estimated by using Kaplan-Meier and Cox proportion regression analysis. P value < 0.05 was considered to declare statistical significance. A total of 200 LN patients were included in the final analysis. Amongst these, the majority of them (91.5%) were females. The median age of the patients was 28 (15-60) years. The mean duration of treatment follow-up was 28 months. The commonly prescribed immunosuppressive drugs during both the induction (49.5%) and maintenance (60%) phases were a combination of mycophenolate mofetil with prednisolone. Complete, partial, and non-responses at the last follow-up visit accounted for 66.5%, 18.0%, and 15.5%, respectively. Patient survival at the last follow-up visit was more than 90% for patients with complete response to the induction therapy. Non-response at the last follow-up visit was significantly associated with severe disease activity index (adjusted odds ratio [AOR] = 6.25, 95% confidence interval [CI] 1.49-26.10), presence of comorbidity (AOR = 0.21, 95% CI 0.05-0.92), baseline leucopenia (AOR = 14.2, 95% CI 1.04-201.3), partial response at the end of induction therapy (AOR = 32.63, 95% CI 1.4-736.0), and duration of induction therapy of greater than 6 months (AOR = 19.47, 95% CI 1.5-258.8). This study unveiled that lower numbers of LN patients were presented with non-response at the last follow-up visit and non-response to induction therapy was associated with lower patients' survival rates compared with complete or partial response.

Macrophage subpopulations in pediatric patients with lupus nephritis and other inflammatory diseases affecting the kidney

BACKGROUND

Macrophages play an important role in the pathogenesis of lupus nephritis (LN), but less is known about macrophage subtypes in pediatric LN. Here we compared renal inflammation in LN with other inflammatory pediatric kidney diseases and assessed whether inflammation correlates with clinical parameters.

METHODS

Using immunofluorescence microscopy, we analyzed renal biopsies from 20 pediatric patients with lupus nephritis (ISN/RPS classes II-V) and pediatric controls with other inflammatory kidney diseases for infiltration with M1-like (CD68 + /CD206 - , CD68 + /CD163 -), M2a-like (CD206 + /CD68 +), and M2c-like macrophages (CD163 + /CD68 +) as well as CD3 + T-cells, CD20 + B-cells, and MPO + neutrophilic granulocytes. In addition, the correlation of macrophage infiltration with clinical parameters at the time of renal biopsy, e.g., eGFR and serum urea, was investigated. Macrophage subpopulations were compared with data from a former study of adult LN patients.

RESULTS

The frequency of different macrophage subtypes in biopsies of pediatric LN was dependent on ISN/RPS class and showed the most pronounced M1-like macrophage infiltration in patients with LN class IV, whereas M2c-like macrophages were most abundant in class III and IV. Interestingly, on average, only half as many macrophages were found in renal biopsies of pediatric LN compared to adult patients with LN. The distribution of frequencies of macrophage subpopulations, however, was different for CD68 + CD206 + (M2a-like) but comparable for CD68 + CD163 - (M1-like) CD68 + CD163 + (M2c-like) cells in pediatric and adult patients. Compared to other inflammatory kidney diseases in children, fewer macrophages and other inflammatory cells were found in kidney biopsies of LN. Depending on the disease, the frequency of individual immune cell types varied, but we were unable to confirm disease-specific inflammatory signatures in our study due to the small number of pediatric cases. Worsened renal function, measured as elevated serum urea and decreased eGFR, correlated particularly strongly with the number of CD68 + /CD163 - M1-like macrophages and CD20 + B cells in pediatric inflammatory kidney disease.

CONCLUSION

Although M1-like macrophages play a greater role in pediatric LN patients than in adult LN patients, M2-like macrophages appear to be key players and are more abundant in other pediatric inflammatory kidney diseases compared to LN.

Identification of novel classes for patients with lupus nephritis using two-step cluster model

OBJECTIVE

To identify and reclassify the patients in the lupus nephritis (LN) cohort, and to further analyze the prominent clinical features and clinical significance of each cluster.

METHODS

In this retrospective cross-sectional study, we used a two-step clustering method to classify 635 patients with LN into different clusters, then we observed the main differences and analyzed relevant clinical significance between the clusters.

RESULTS

Cluster 1 (20.5%) presented with the highest disease severity, patients in this group had the disease for a longer duration and higher systemic lupus erythematosus disease activity index (SLEDAI) score, with multiple positive auto-antibodies and lower complement level. Patients of cluster 2 (20.8%) had lower levels of IgG, IgA and IgM, with renal function being relatively worse in this cluster than in clusters 1 and 3. Cluster 3 was the largest group (58.7%), and the patients in this group showed mild disease severity.

CONCLUSION

This study reclassified LN patients in a large cohort into three clusters. Our classification might be helpful to implement targeted therapy at various stages of systemic lupus erythematosus.

Kidney Level Lupus Nephritis Classification Using Uncertainty Guided Bayesian Convolutional Neural Networks

The kidney biopsy based diagnosis of Lupus Nephritis (LN) is characterized by low inter-observer agreement, with misdiagnosis being associated with increased patient morbidity and mortality. Although various Computer Aided Diagnosis (CAD) systems have been developed for other nephrohistopathological applications, little has been done to accurately classify kidneys based on their kidney level Lupus Glomerulonephritis (LGN) scores. The successful implementation of CAD systems has also been hindered by the diagnosing physician's perceived classifier strengths and weaknesses, which has been shown to have a negative effect on patient outcomes. We propose an Uncertainty-Guided Bayesian Classification (UGBC) scheme that is designed to accurately classify control, class I/II, and class III/IV LGN (3 class) at both the glomerular-level classification task (26,634 segmented glomerulus images) and the kidney-level classification task (87 MRL/lpr mouse kidney sections). Data annotation was performed using a high throughput, bulk labeling scheme that is designed to take advantage of Deep Neural Network's (or DNNs) resistance to label noise. Our augmented UGBC scheme achieved a 94.5% weighted glomerular-level accuracy while achieving a weighted kidney-level accuracy of 96.6%, improving upon the standard Convolutional Neural Network (CNN) architecture by 11.8% and 3.5% respectively.

The ISN/RPS 2016 classification predicts renal prognosis in patients with first-onset class III/IV lupus nephritis

Lupus nephritis (LN) is a life-threatening complication of systemic lupus erythematosus. The 2003 pathological classification of LN was revised in 2016; it quantitatively evaluates the interstitium in addition to the glomeruli. We performed a retrospective multi-centre cohort study and investigated the utility of the 2016 classification—including the activity index (AI), chronicity index (CI), and each pathological component to predict complete remission or renal function decline, defined as 1.5-fold increase in serum creatinine levels—and compare with that of the 2003 classification. Ninety-one consecutive adult patients with first-onset class III/IV LN who were newly prescribed any immunosuppressants were enrolled and followed up for a median of 51 months from January 2004. Cox regression analysis demonstrated the subclasses based on the 2003 classification, which mainly evaluate glomerular lesions, were not associated with clinical outcomes. After adjustments for estimated glomerular filtration rate and urinary protein levels, higher CI and higher interstitial fibrosis and lower hyaline deposit scores were associated with renal functional decline. Similarly, higher CI and interstitial inflammation scores were associated with failure to achieve complete remission. Therefore, the 2016 classification can predict the clinical outcomes more precisely than the 2003 classification.

Retinoic Acid Exerts Disease Stage-Dependent Effects on Pristane-Induced Lupus

We previously showed that all-trans-retinoic acid (tRA), an active metabolite of vitamin A, exacerbated pre-existing autoimmunity in lupus; however, its effects before the development of autoimmunity are unknown. Here, using a pristane-induced model, we show that tRA exerts differential effects when given at the initiation vs. continuation phase of lupus. Unlike tRA treatment during active disease, pre-pristane treatment with tRA aggravated glomerulonephritis through increasing renal expression of pro-fibrotic protein laminin β1, activating bone marrow conventional dendritic cells (cDCs), and upregulating the interaction of ICAM-1 and LFA-1 in the spleen, indicating an active process of leukocyte activation and trafficking. Transcriptomic analysis revealed that prior to lupus induction, tRA significantly upregulated the expression of genes associated with cDC activation and migration. Post-pristane tRA treatment, on the other hand, did not significantly alter the severity of glomerulonephritis; rather, it exerted immunosuppressive functions of decreasing circulatory and renal deposition of autoantibodies as well as suppressing the renal expression of proinflammatory cytokines and chemokines. Together, these findings suggest that tRA differentially modulate lupus-associated kidney inflammation depending on the time of administration. Interestingly, both pre- and post-pristane treatments with tRA reversed pristane-induced leaky gut and modulated the gut microbiota in a similar fashion, suggesting a gut microbiota-independent mechanism by which tRA affects the initiation vs. continuation phase of lupus.

A clinico-pathological study of lupus nephritis based on the International Society of Nephrology-Renal Pathology Society 2003 classification system

INTRODUCTION

Lupus nephritis (LN) is a major complication of systemic lupus erythematosus (SLE). Renal involvement is a major determinant of the prognosis of SLE. The histological classification of LN is a key factor in determining the renal survival of patients with LN. Prompt recognition and treatment of renal disease are important, as early response to therapy is correlated with better outcome and renal biopsy plays an important role in achieving this.

OBJECTIVES

The objective of this study was to correlate the clinical and laboratory findings with histopathological classes of LN as per the 2003 International Society of Nephrology-Renal Pathology Society (ISN/RPS) classification system.

PATIENTS AND METHODS

Fifty-six patients with SLE, undergoing a renal biopsy for renal dysfunction were studied. The comparison of data from multiple groups was made by Pearson's Chi-square test and between two groups by independent samples t-test. The values of P < 0.05 were considered statistically significant.

RESULTS

Of the 56 cases studied, 51 (91.1%) were females. The most common presenting symptoms were edema, arthralgia, and hypertension. Class IV (55.4%) was the most common class. Thirty-nine (69.6%) cases showed full house immunostaining. Hypertension, hematuria, proteinuria, and tubulo-interstitial disease showed a significant correlation (P < 0.05) with ISN/RPS classification, 2003.

CONCLUSION

Assessment and management of patients with suspected LN are greatly facilitated through information obtained by renal biopsy. Since renal morphology may predict long-term prognosis, and no clinical or laboratory feature uniformly predicts prognosis, it is important to study the constellation of features in LN for better patient management.

The new complement inhibitor CRIg/FH ameliorates lupus nephritis in lupus-prone MRL/lpr mice

Backgrounds

The aberrant activation of complement system is critically involved in lupus nephropathy. Recent study showed complement C3 inhibitor was effective in the treatment of lupus nephropathy. In this study, we investigate the effect of a novel complement C3 inhibitor, CRIg/FH, in the treatment of lupus nephropathy in MRL/lpr lupus mice.

Methods

We treated MRL/lpr female mice with a dose escalation of CRIg/FH (10, 5 and 2 mg/kg) by intraperitoneal injection twice weekly since 12 weeks age. In addition, MRL/lpr mice treated with intraperitoneal injection of normal saline or oral prednisone, along with C57BL/6 J healthy mice were maintained to serve as controls. We started 8-h urine collection weekly to screen proteinuria by measuring the levels of urine urea/creatinine. Serum samples was collected at week 16 and 20 to measure levels of urea nitrogen, creatinine, and immunological markers (C3, C4, A-ds-DNA) before the mice were sacrificed at 20 weeks age to collect kidneys for histopathological examinations.

Results

Overt skin lesions were observed in MRL/lpr mice treated with normal saline, while skin lesion was not observed in CRIg/FH treated MRL/lpr mice. There was no overt proteinuria observed in MRL/lpr mice treated with CRIg/FH. Serum creatinine and BUN levels in MRL/lpr mice was maintained in highest CRIg/FH dose (10 mg/kg twice a week) to be significantly lower than that in prednisone treated MRL/lpr mice at 20 weeks age. In addition, CRIg/FH treatment in MRL/lpr mice results in a significantly elevated serum C3 and C4 levels when compared to prednisone treatment at both 16 and 20 weeks. Furthermore, our study identified that serum level of A-ds-DNA was also significantly lower in CRIg/FH treatment than that in predisone treated MRL/lpr mice. Renal pathology confirmed that kidneys from CRIg/FH treated MRL/lpr mice suffered less from nephritis and complement disposition.

Conclusion

Our results showed that the complement inhibitor CRIg/FH can protect MRL/lpr mice from lupus nephropathy by preserving renal function and glomerulus complement activation. Our findings support the positive effect of complement inhibitors in the treatment of lupus nephropathy.

A Systematic Review of Interpathologist Agreement in Histologic Classification of Lupus Nephritis

Introduction

Lupus nephritis (LN) is one of the most severe manifestations of systemic lupus erythematosus (SLE), resulting in increased morbidity and mortality. The gold standard for diagnosis of LN is a renal biopsy. Considering the importance of the biopsy in determining long-term prognostication and treatment decisions, it is crucial to assess renal histopathology with utmost accuracy and precision. This review represents a systematic search of published literature to estimate the degree of interpathologist reproducibility in current assessment of LN.

Methods

Using the PubMed and Google Scholar search engines, studies analyzing the agreement of 4 or more pathologists assessing LN slides using the ISN/Renal Pathology Society (RPS) classification, activity index, and chronicity index were selected for analysis in this systematic review.

Results

In reviewing 6 qualifying studies (those analyzing the agreement of 4 or more pathologists using the ISN/RPS classification, activity index, and chronicity index) for the assignment of ISN/RPS class was 0.325 (interquartile range [IQR] 0.2405–0.425), which is “poor.” The median interpathologist concordance values for the assigned activity index and chronicity index were “moderate”: 0.52 (IQR 0.51–0.69) and 0.49 (IQR 0.36–0.58), respectively.

Conclusion

Thus, the current scoring using the ISN/RPS classification system and activity and chronicity indices for LN exhibits poor interpathologist agreement, which limits its use in clinical practice. Given that this can have severe repercussions on a patient’s treatment and prognosis, efforts to update pathology assessment guidelines, objectively measurable biomarkers, and deep learning approaches are strongly warranted.

The clinical significance of plasma CFHR 1-5 in lupus nephropathy

A deficiency of complement factor H may lead to excessive consumption of C3 and an increase in C3b deposition, which are important pathological characteristics of lupus nephritis. Complement factor H-related proteins (CFHRs), comprising CFHR1 to CFHR5 (CFHR1-5), are members of the wider factor H/CFHR family. Their role in lupus nephritis remains unclear. In this study, we compared circulating levels of CFHR1-5 in 152 patients diagnosed with lupus nephritis and 20 unrelated healthy individuals to explore the relationship between the expression of CFHR1-5 and development of the disease. We found that plasma levels of CFHR3 and CFHR5 were higher in patients with lupus nephritis than in healthy individuals; also, CFHR3 and CFHR5 concentrations increased with increasing systemic lupus erythematosus disease activity index (SLEDAI) values (P < 0.05). Pearson's and Spearman's correlation test results confirmed that plasma CFHR3 and CFHR5 levels in lupus nephritis patients were positively correlated with proteinuria and levels of creatinine (Cr) and anti-dsDNA (correlation coefficients = 0.491-0.717, P < 0.05), while they were negatively correlated with plasma C3 levels and eGFR [correlation coefficients = -(0.706-0.788), P < 0.05]. Receiver operating characteristic (ROC) curve analysis results confirmed that plasma CFHR3 and CFHR5 levels were predictive of SLEDAI values and disease end points (area under the curve = 0.664-0.884, P < 0.05), with patients with both high CFHR3 and high CFHR5 exhibiting the shortest progression-free survival. Thus, both CFHR3 and CFHR5 are of prognostic value in lupus nephritis status.

Inhibition of IL-17 ameliorates systemic lupus erythematosus in Roquinsan/san mice through regulating the balance of TFH cells, GC B cells, Treg and Breg

Systemic lupus erythematosus (SLE) is mediated by a chronic and dysregulated inflammatory response. Interleukin (IL)-17, a proinflammatory cytokine, and T helper (Th)17 cells are associated with chronic autoimmune diseases. We hypothesized that inhibition of IL-17 would decrease the numbers of T cell subsets that function as B-cell helpers, as well as B-cell differentiation into plasma cells and autoantibody expression. The IL-17 level was increased markedly in Roquin^san/san mice. Loss of IL-17 in Roquin^san/san mice improved nephritis by downregulating immunoglobulin (Ig)G, IgG1, and IgG2a production. Formation of germinal centers (GCs), and follicular B- and T-cell differentiation was reduced, whereas the number of regulatory T (Treg) cells and immature B cells was increased, by IL-17 deficiency in Roquin^san/san mice. These results suggest that IL-17 inhibition can ameliorate SLE by inhibiting B-cell differentiation into GCs. Therefore, IL-17–producing Th17 cells show promise as a target for development of novel therapeutics for SLE.

The potential diagnostic utility of coexpression of Ki-67 and P53 in the renal biopsy in pediatric lupus nephritis

Background

The proliferative activity as well as apoptosis has been suggested to play a role in the pathogenesis of lupus nephritis (LN). The aim of the study was to investigate the coexpression of Ki-67-triggered marked proliferation and P53-induced apoptosis in renal biopsy of childhood lupus nephritis (cLN) and to compare the coexpression of proliferative and apoptotic indices between different subgroups and clinicopathologic patterns of renal disease.

Methods

Renal biopsy specimens of 33 children with lupus nephritis (LN) and 10 healthy subjects were retrospectively evaluated. The type of LN and activity and chronicity indices were determined. Ki-67 and P53 immunostaining were performed. The coexpression of Ki-67 and P53 was compared among different subgroups of LN and correlated with disease activity index, serum creatinine, proteinuria, anticardiolipin antibodies, and complement levels. Histopathological examination of LN was classified based on the International Society of Nephrology/Renal Pathology. Histological LN activity was measured by the National Institutes of Health activity index (NIH-AI).

Results

In comparison with the healthy control group, the coexpression of Ki-67and P53 was greater in cLN (particularly in classes II, III, and IV) than in normal renal tissue. The coexpression of Ki-67and P53 shows a positive correlation with subclasses II, III, and IV of LN (P<0.02) and LN activity index (P<0.03). Moreover, the positive correlation was found between the coexpression of Ki-67 and P53 with erythrocyte sedimentation rate (P<0.02), D-dimer (P<0.03), serum creatinine (P<0.03), proteinuria (P<0.04), and anticardiolipin antibodies (P<0.05) significantly. Unexpectedly, adverse correlation between the coexpression of Ki-67 and P53 with serum C3 (P<0.02) and C4 complement (P<0.03) was significant.

Conclusion

Our data showed that the coexpression of Ki-67-induced marked proliferation and P53-induced apoptosis in proliferative and active phases of cLN could reflect a valuable marker for treatment and remission in cLN patients before reaching the end stage of renal disease.

Outcomes of rituximab therapy in refractory lupus: A meta-analysis

OBJECTIVE

Conventional treatment of systemic lupus erythematosus (SLE) and lupus nephritis (LN) is associated with damage accrual, hence increased morbidity rate. Off-label use of rituximab (RTX) has shown significant promise in this patient group; however, data are still controversial. We aimed to analyze the outcomes of RTX therapy in refractory lupus using a meta-analysis approach.

METHODS

Electronic search of the medical literature was conducted using a combination of relevant keywords to retrieve studies on the safety and efficacy of RTX in SLE and LN patients. Results were screened against our inclusion and exclusion criteria and two reviewers independently extracted the data for analysis. Comprehensive meta-analysis software was used to pool the data from individual studies and provide summary effect estimates.

RESULTS

Thirty-one studies that enrolled 1112 patients were finally eligible for the meta-analysis. The overall global, complete, and partial response rates to RTX therapy were 72%, 46%, and 32%, respectively. RTX significantly decreased Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and British Isles Lupus Activity Group (BILAG) scores (p<0.001). Prednisone dose was significantly reduced after RTX treatment in both SLE and LN groups (p<0.001), and proteinuria was lowered in SLE (p<0.001) than in LN patients (p=0.07). Infection and infusion-related reactions were the most common side effects.

CONCLUSION

RTX therapy in refractory SLE and LN patients proved clinical efficacy and favorable safety outcomes. Larger well-designed randomized clinical trials are warranted.

Metformin Suppresses Systemic Autoimmunity in Roquinsan/san Mice through Inhibiting B Cell Differentiation into Plasma Cells via Regulation of AMPK/mTOR/STAT3

Circulating autoantibodies and immune complex deposition are pathological hallmarks of systemic lupus erythematosus (SLE). B cell differentiation into plasma cells (PCs) and some T cell subsets that function as B cell helpers can be therapeutic targets of SLE. Mechanistic target of rapamycin (mTOR) signaling is implicated in the formation of B cells and germinal centers (GCs). We assessed the effect of metformin, which inhibits mTOR, on the development of autoimmunity using Roquin^san/san mice. Oral administration of metformin inhibited the formation of splenic follicles and inflammation in kidney and liver tissues. It also decreased serum levels of anti-dsDNA Abs without affecting serum glucose levels. Moreover, metformin inhibited CD21^highCD23^low marginal zone B cells, B220⁺GL7⁺ GC B cells, B220^-CD138⁺ PCs, and GC formation. A significant reduction in ICOS⁺ follicular helper T cells was found in the spleens of the metformin-treated group compared with the vehicle-treated group. In addition, metformin inhibited Th17 cells and induced regulatory T cells. These alterations in B and T cell subsets by metformin were associated with enhanced AMPK expression and inhibition of mTOR-STAT3 signaling. Furthermore, metformin induced p53 and NF erythroid-2-related factor-2 activity in splenic CD4⁺ T cells. Taken together, metformin-induced alterations in AMPK-mTOR-STAT3 signaling may have therapeutic value in SLE by inhibiting B cell differentiation into PCs and GCs.

ISN/RPS 2003 classification of lupus nephritis: time to take a look on the achievements and limitations of the schema

Implication for health policy/practice/research/medical education:

Lupus nephritis (LN) is the most dreadful complication of systemic lupus erythematosus (SLE) and is responsible for the major share of morbidity and mortality of this disease. Its diagnosis, classification and management have posed significant challenges to the nephrologists and pathologists over the past several decades. A series of WHO classifications of LN were followed by the development of the international society of nephrology/renal pathology society (ISN/RPS) classification of LN in 2003. The classification has largely succeeded in achieving its goals, but a few limitations have also been exposed. It is time to revisit the classification in the light of experience of validation studies and new emerging data on this disease.

Lupus nephritis: review of the literature

Physicians in practice should be knowledgeable regarding several aspects of autoimmune disorders, especially systemic lupus erythematosus (SLE) and lupus nephritis. These disorders can present to the clinician's clinic and private office regardless of their specialty. This review will discuss various aspects of SLE, its mechanisms of disease, role of accelerated atherosclerosis, proinflammatory cytokines, and therapeutic approaches. The role of vascular endothelial growth factor in which and plasma levels have been associated with disease activity, classification of severity, and diagnosis of lupus nephritis is addressed. Current treatment options, prognosis, and future therapeutic approaches and common side effects are also discussed.

Predictors of survival in Chinese patients with lupus nephritis

The current study was to determine the predictors of survival in 491 Chinese patients with lupus nephritis (LN). All patients were evaluated and consecutively followed up from 2003 to 2010. The female: male ratio was 9.5:1, with a median age of 31.1 ± 12 years. Forty-nine (10.0%) patients were lost to follow-up and 47 (10.3%) patients died. The overall cumulative probability of survival at 5, 10, 15 and 20 years by Kaplan-Meier analysis was 88%, 77%, 53% and 45%, respectively. The log-rank test showed that the probability of survival was significantly decreased in the late-onset patients (≥50 years) ( P = 0.036), patients with hypoproteinaemia (≤35 g/l) ( P = 0.014), patients with increased creatinine (≥1.5 mg/dl) ( P = 0.002) and patients with massive proteinuria (≥3.5 g/24 h) ( P = 0.009). However, the probability of survival was significantly higher in patients treated with hydroxychloroquine (HCQ) ( P = 0.003) than those not treated with it. Based on a multivariate model, increased creatinine (hazard ratio (HR) = 2.041; P = 0.017) and proteinuria ≥3.5 g/24hours (HR=1.716; P = 0.016) were independent risk factors. Glucocorticoid (HR = 0.457; P = 0.01) and HCQ (HR=0.197; P = 0.026) were independent protective factors. Our findings suggest that renal dysfunction and massive proteinuria are independent risk factors for mortality. HCQ could improve the survival of patients with LN.

Predictors of chronic kidney disease in Korean patients with lupus nephritis

OBJECTIVE

Since chronic kidney disease (CKD) is closely associated with cardiovascular disease and mortality as well as endstage renal disease, prediction of progressive CKD is a clinically important issue. We investigated the independent risk factors for the development of CKD in patients with lupus nephritis (LN).

METHODS

The cohort included 322 Korean patients diagnosed with LN between 1985 and 2010. We retrospectively analyzed the clinical and laboratory indices, treatment response, the final renal function, and the biopsy findings. The timing and cumulative risk of developing CKD were identified by Kaplan-Meier methods. The independent risk factors for developing CKD were examined by univariate and multivariate Cox proportional hazards regression analyses.

RESULTS

The median followup time after the diagnosis of LN was 84 months. CKD occurs in 22% of the patients within 10 years after the diagnosis of LN. The probability of developing CKD was significantly associated with the onset time of LN (delayed-onset LN vs initial-onset LN; HR 2.904, p = 0.003), deteriorated renal function [an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m(2) body surface area] at the onset of LN (HR 7.458, p < 0.001), relapse of LN after achieving remission (HR 2.806, p = 0.029), and resistance to induction therapy (HR 8.120, p < 0.001).

CONCLUSION

Our results demonstrate that delayed-onset LN, a decreased eGFR at the time of LN onset, and the failure to achieve a sustained remission are predictors for the development of CKD in Korean patients with LN.