Predictors of renal outcome in diffuse proliferative lupus nephropathy: data from repeat renal biopsy

A Histology-Guided Approach to the Management of Patients with Lupus Nephritis: Are We There Yet?

Renal involvement is a frequent complication of systemic lupus erythematosus (SLE). It occurs in up to two-thirds of patients, often early during the disease course, and is the most important predictor of the morbidity and mortality of SLE patients. Despite tremendous improvements in the approach of the lupus nephritis (LN) therapy, including the recent approval of two new disease-modifying therapies, up to 50% of patients do not obtain a renal response and up to 25% will eventually progress to end-stage renal disease (ESRD) within 10 years of diagnosis. Given the lack of correlation between clinical features and histological lesions, there is an increasing need for a histology-guided approach to the management of patients with LN. Apart from the initial diagnosis of type and severity of renal injury in SLE, the concept of a repeat kidney biopsy (either in a for-cause or a per-protocol scenario) has begun to gain increasing popularity in the nephrology community. Herein, we will provide a comprehensive overview of the most important areas of utility of the kidney biopsy in patients with LN.

Clinicopathological study of males with lupus nephritis: Pathologist's experience at a tertiary-care center

Background:

Systemic lupus erythematosus (SLE) is an autoimmune systemic disorder, more common in females of reproductive age-group as compared with males. There are very few studies regarding lupus nephritis (LN) in males. Hence, we decided to study the clinical and pathological findings of LN in males.

Materials and Methods:

We carried out a retrospective study over a period of 5 years (January 2014–December 2018) on indicated native renal biopsies from male patients with LN. We analyzed the clinical, laboratory, and histological findings of these patients.

Results:

Renal biopsies were performed on 228 patients with LN, of which 29 (12.72%) biopsies were in male patients. The mean age at presentation was 28.3 ± 12.98 years. Edema (65.5%) was the most common clinical feature followed by arthritis (27.58%), fever (27.58%), and skin rash (24.1%). The mean values for 24 hours urinary protein, serum double-stranded DNA, serum antinuclear antibody, and serum complement C3 were 4.98 ± 2.91 g, 137.7 ± 91.93 IU/mL, 2.96 ± 1.78, and 65.07 ± 36.30 mg/dL, respectively. On histology, the most common class of LN was Class IV (34.48%) followed by Class V (20.68%), combined Class IV + V (20.68%), Classes II, III, and III + V.

Conclusion:

LN can affect males, although the prevalence is lower than in females. The incidence of LN in our study was 12.7% with the most common histological class being diffuse proliferative LN.

Comparison of complete renal response and mortality in early- and late-onset lupus nephritis: a multicenter retrospective study of a Japanese cohort

Background

Most patients with systemic lupus erythematosus (SLE) progress to lupus nephritis (LN) within 5 years of their SLE diagnosis, although it is not uncommon for LN to develop at later time points. Here we evaluated the clinical features of early- and late-onset LN.

Patients and methods

We retrospectively analyzed the cases of 184 of the 201 patients who underwent a renal biopsy at Nagasaki University Hospital and associated community hospitals between 1990 and 2016 and were diagnosed as having LN. Early onset was defined as the development of LN within the first 5 years after the patient’s SLE diagnosis, and late onset was defined as LN development > 5 years post-diagnosis. We analyzed the complete renal response (CR) at 6 and 12 months after induction therapy, the classification of renal pathology, and the mortality of the early- and late-onset LN groups.

Results

The mean follow-up duration after the renal biopsy was 123 ± 85 months. There were 113 (61.4%) early-onset patients and 71 (38.6%) late-onset patients. A multivariate analysis revealed that the following factors were predictive of CR: at 6 months: female sex (odds ratio [OR] 3.93, 95% confidence interval [CI] 1.31–11.77, p = 0.010), proteinuria (OR 0.83, 95% CI 0.71–0.97, p = 0.009), index of activity (0–24) (OR 0.83, 95% CI 0.70–0.99, p = 0.030), and early-onset LN (OR 2.39, 95% CI 1.15–4.98, p = 0.018); at 12 months: female sex (OR 3.60, 95% CI 1.32–9.83, p = 0.013), mixed LN (OR 0.18, 95% CI 0.04–0.80, p = 0.024), index of activity (0–24) (OR 0.80, 95% CI 0.68–0.94, p = 0.007), and early-onset LN (OR 2.10, 95% CI 1.05–4.23, p = 0.035). In a Cox proportional hazards and Fine-Gray regression model, the early-onset LN group had a significantly better mortality rate than the late-onset LN group (p = 0.038 and p = 0.043, respectively).

Conclusions

In our cohort, early-onset LN was a better predictor of CR at 6 and 12 months than late-onset LN. Our results suggest that early-onset LN patients had lower mortality than late-onset LN patients.

Urinary activated leukocyte cell adhesion molecule as a novel biomarker of lupus nephritis histology

Background

Lupus nephritis (LN) is one of the most severe complications of SLE patients. We aim to validate urinary ALCAM as a biomarker in predicting renal disease histpathology in a Chinese lupus cohort.

Methods

In this cross-sectional study, a total of 256 patients and controls were recruited. Urinary levels of ALCAM were determined by ELISA. Renal histopathology was reviewed by an experienced renal pathologist.

Results

Urinary ALCAM levels were significantly increased in active LN patients when compared to active SLE patients without renal involvement (p < 0.001), inactive LN patients (p = 0.023), inactive SLE patients without renal involvement (p < 0.001), and healthy controls (p < 0.001). Correlation analysis revealed a positive correlation between urinary ALCAM and general disease activity—SLEDAI score (r = 0.487, p < 0.001), as well as renal disease activity—rSLEDAI (r = 0.552, p < 0.001) and SLICC RAS (r = 0.584, p < 0.001). Urinary ALCAM also correlated with lab parameters including 24-h urine protein, hemoglobin, and complement 3. Moreover, urinary ALCAM levels were significantly increased in class III and IV (proliferative) LN as compared to those in class V (membranous) LN. It outperformed conventional biomarkers (anti-dsDNA antibody, C3, C4, proteinuria) in discriminating the two groups of LN. On renal histopathology, urinary ALCAM levels correlated positively with activity index (r = 0.405, p < 0.001) but not chronicity index (r = 0.079, p = 0.448).

Conclusion

Urinary ALCAM is a potential biomarker for predicting renal pathology activity in LN and may serve as a valuable surrogate marker of renal histopathology.

Glomerular Expression of Some Profibrotic Factors in Progressive Childhood Lupus Nephritis

BACKGROUND

Lupus nephritis (LN) is a major cause of mortality and morbidity in both adult and pediatric patients. However, studies regarding pathogenesis and predictors of renal outcomes in childhood LN are limited. Transforming growth factor-β1 (TGF-β1) and Connective tissue growth factor (CTGF) have an important role in proliferative and fibrotic changes in many renal diseases. We aim to evaluate the role of such two profibrotic factors in the progression of childhood onset LN and to detect if their glomerular expression could represent an early predictor of future deterioration of renal function.

METHODS

34 children with new onset of LN were included. Glomerular expressions of TGF-β1 and CTGF were evaluated by immunohistochemical analysis in the renal tissue of such patients and in control tissue. GFR was estimated at time of renal biopsy at the onset of LN and after 2 years of follow-up. Rate of GFR change (ΔGFR) was calculated and used as indicative of degree of renal disease progression.

RESULTS

Glomerular TGF-β1 and CTGF expressions in children with LN were significantly higher than in control tissue (LN 15.41 ± 9.84 and 15.56 ± 10.51 vs. 2.15 ± 1.45 and 1.35 ± 1.07 in control respectively, with p < 0.001 in both). In addition, the glomerular expressions of TGF-β1 and CTGF were significantly higher in patients with further decline in GFR (20.68 ± 7.73 and 21.05 ± 8.75) versus (5.75 ± 4.37 and 5.50 ± 3.78) in those without change in GFR with (p = 0.000 for both of them).

CONCLUSIONS

Patients with LN have increased glomerular expressions of TGF-β1 and CTGF, which were higher in those with further decline in GFR. These profibrotic factors are suspected to be involved in pathogenesis of LN and could be evaluated as a target for therapeutic intervention to stop progression of LN. In addition, their glomerular expression could be used as an early predictor of progression of LN, to justify early aggressive therapy in those with suspected rapid progression.

Factors predictive of long-term mortality in lupus nephritis: a multicenter retrospective study of a Japanese cohort

Background

Lupus nephritis (LN) is a major determinant of mortality in systemic lupus erythematosus (SLE). Here we evaluated the association between complete renal response (CR) and mortality in LN.

Methods

We retrospectively analyzed the cases of 172 of 201 patients with LN for whom data on the therapeutic response at 6 and 12 months after induction therapy were available. The patients underwent a renal biopsy at Nagasaki University Hospital and community hospitals in Nagasaki between the years 1990 and 2016. We determined the CR rates at 6 and 12 months after induction therapy initiation and evaluated the predictive factors for CR and their relationship with mortality. We performed univariate and multivariable competing risks regression analyses to determine the factors predictive of CR. The patients' survival data were analyzed by the Kaplan–Meier method with a log-rank test.

Results

The median follow-up duration after renal biopsy was 120 months (interquartile range: 60.3–191.8 months). The 5-, 10-, 15- and 20-year survival rates of our cohort were 99.3, 94.6, 92.0 and 85.4%, respectively. During follow-up, nine patients (5.2%) died from cardiovascular events, infection, malignancy and other causes. The multivariate analysis revealed that the following factors were predictive of CR. At 6 months: male gender (odds ratio (OR) 0.23, 95% confidence interval (CI) 0.08–0.65, p = 0.0028), proteinuria (g/gCr) (OR 0.83, 95% CI 0.71–0.97, p = 0.0098) and index of activity (0–24) (OR 0.84, 95% CI 0.71–0.99, p = 0.0382). At 12 months: male gender (OR 0.25, 95% CI 0.09–0.67, p = 0.0043) and index of activity (0–24) (OR 0.82, 95% CI 0.69–0.98, p = 0.0236). The Kaplan–Meier analysis showed that compared to not achieving CR at 12 months, achieving CR at 12 months was significantly correlated with the survival rate (OR 0.18, 95% CI 0.04–0.92, p = 0.0339).

Conclusions

Our results suggest that the survival rate of patients with LN is associated with the achievement of CR at 12 months after induction therapy, and that male gender and a higher index of activity (0–24) are the common predictive factors for failure to achieve CR at 6 and 12 months.

Podocyte foot process width is a prediction marker for complete renal response at 6 and 12 months after induction therapy in lupus nephritis

Morphological change that includes diffuse effacement of podocyte foot processes is correlated with proteinuria in patients with lupus nephritis (LN). We collected the data of clinico-pathological parameters and assessed foot process width (FPW) as an index of podocyte effacement in 73 patients with LN who had undergone renal biopsy. The multivariate analysis revealed that female gender (OR: 5.288; 95%CI: 1.197-37.29; p = .0267) and FPW (OR = 0.999, 95%CI = 0.997-0.999, p = .0150) were significantly predictive of a complete renal response (CR) at 6 months, while lymphocyte counts (OR = 1.002; 95%CI = 1.001-1.003, p = .0028) and FPW (OR = 0.998, 95%CI = 0.996-0.999, p = .0027) were significantly predictive of CR at 12 months. The cut-off point determined by the Classification and Regression Trees algorithm showed that FPW <908.3 nm provides the best performance for predicting patients who achieve CR at 12 months. A smaller FPW appears to be a predictive factor for CR at 6 and 12 months after induction therapy.

The clinical relevance of repeat renal biopsies in the management of lupus nephritis: a South African experience

Purpose Clinically, repeat renal biopsies (RRBs) have been performed in lupus nephritis to identify changes in class, plan treatment and assist in prognostication. We set out to compare the histopathological features and outcomes of disease flare and protocol biopsy patients. Methods A retrospective descriptive study was conducted on repeat biopsies performed between January 1984 and December 2015 in lupus nephritis patients. Disease flares and protocol biopsies were compared. Results Of 614 systemic lupus erythematosus (SLE) renal biopsies, 127 (20.7%) RRBs were identified. Disease flare patients accounted for 96 (75.6%) and protocol biopsies for 31 (24.4%) of RRBs. Seventy (72.9%) disease flare patients retained their original class on repeat biopsy. When categorised as proliferative and non-proliferative histology, 83 (87.4%) of the disease flare biopsy patients remained histologically unchanged. Treatment remained unchanged in 57 (60.0%) patients following RRBs for disease flares. Response to immunosuppression in disease flare patients was poorer. Non-response was associated with increased chronicity index (OR = 1.33; 95% CI 1.01-1.76; p = 0.045). Thirty-three (36.3%) disease flare patients developed end-stage kidney disease (ESKD) in one year as compared to one (3.6%) protocol biopsy patient ( p = 0.003). ESKD in disease flare patients was associated with non-response to treatment (OR = 24.6; 95% CI 2.7-219.3; p = 0.004) on multivariate analysis. One-year mortality was 30.0% in the disease flare patients and 3.5% in protocol biopsy patients ( p = 0.018). Conclusion Repeat biopsies in disease flare patients infrequently led to histological class changes, failed to lead to change of treatment in the majority of patients, and were associated with poorer outcomes.

The value of repeat biopsy in lupus nephritis flares

Whether a repeat renal biopsy is helpful during lupus nephritis (LN) flares remains debatable. In order to analyze the clinical utility of repeat renal biopsy in this complex situation, we retrospectively reviewed our series of 54 LN patients who had one or more repeat biopsies performed only on clinical indications. Additionally, we reviewed 686 well-documented similar cases previously reported (PubMed 1990-2015).The analysis of all patients reviewed showed that histological transformations are common during a LN flare, ranging from 40% to 76% of cases. However, the prevalence of transformations and the clinical value of repeat biopsy vary when they are analyzed according to proliferative or nonproliferative lesions.The great majority of patients with class II (78% in our series and 77.5% in the literature review) progressed to a higher grade of nephritis (classes III, IV, or V), resulting in worse renal prognosis. The frequency of pathological conversion in class V is lower (33% and 43%, respectively) but equally clinically relevant, since almost all cases switched to a proliferative class. Therefore, repeat biopsy is highly advisable in patients with nonproliferative LN at baseline biopsy, because these patients have a reasonable likelihood of switch to a proliferative LN that may require more aggressive immunosuppression.In contrast, the majority of patients (82% and 73%) with proliferative classes in the reference biopsy (III, IV or mixed III/IV + V), remained into proliferative classes on repeat biopsy. Although rebiopsy in this group does not seem as necessary, it is still advisable since it will allow us to identify the 18% to 20% of patients that switch to a nonproliferative class. In addition, consistent with the reported clinical experience, repeat biopsy might also be helpful to identify selected cases with clear progression of proliferative lesions despite the initial treatment, for whom it is advisable to intensify inmunosuppression. Thus, our experience and the literature data support that repeat biopsy also brings more advantges than threats in this group.The results of the repeat biopsy led to a change in the immunosuppresive treatment in more than half of the patients on average, intensifying it in the majority of the cases, but also reducing it in 5% to 30%.

A discrete cluster of urinary biomarkers discriminates between active systemic lupus erythematosus patients with and without glomerulonephritis

Background

Management of lupus nephritis (LN) would be greatly aided by the discovery of biomarkers that accurately reflect changes in disease activity. Here, we used a proteomics approach to identify potential urinary biomarkers associated with LN.

Methods

Urine was obtained from 60 LN patients with paired renal biopsies, 25 active non-LN SLE patients, and 24 healthy controls. Using Luminex, 128 analytes were quantified and normalized to urinary creatinine levels. Data were analyzed by linear modeling and non-parametric statistics, with corrections for multiple comparisons. A second cohort of 33 active LN, 16 active non-LN, and 30 remission LN SLE patients was used to validate the results.

Results

Forty-four analytes were identified that were significantly increased in active LN as compared to active non-LN. This included a number of unique proteins (e.g., TIMP-1, PAI-1, PF4, vWF, and IL-15) as well as known candidate LN biomarkers (e.g., adiponectin, sVCAM-1, and IL-6), that differed markedly (>4-fold) between active LN and non-LN, all of which were confirmed in the validation cohort and normalized in remission LN patients. These proteins demonstrated an enhanced ability to discriminate between active LN and non-LN patients over several previously reported biomarkers. Ten proteins were found to significantly correlate with the activity score on renal biopsy, eight of which strongly discriminated between active proliferative and non-proliferative/chronic renal lesions.

Conclusions

A number of promising urinary biomarkers that correlate with the presence of active renal disease and/or renal biopsy changes were identified and appear to outperform many of the existing proposed biomarkers.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-016-1120-0) contains supplementary material, which is available to authorized users.

High collagen I gene expression as an independent predictor of adverse renal outcomes in lupus nephritis patients with preserved renal function

CONTEXT

The deposition of extracellular matrix is a major pathogenic mechanism leading to fibrosis and progressive decline in renal function in patients with lupus nephritis (LN). Currently, available clinicopathologic features cannot predict renal outcome consistently.

OBJECTIVE

To test that the expression of renal fibrogenic genes correlates with renal fibrosis at the time of biopsy and is predictive of renal outcomes.

DESIGN

Renal gene expression levels of transforming growth factor β-1 (TGFB1), and collagen I (COL1) were studied by real-time multiplex quantitative polymerase chain reaction in a prospective cohort of patients with LN (n = 39). Extracellular matrix index (ECMI) and collagen I/III matrix index were measured from Picro-Sirius Red-stained slides under normal and polarized light, respectively.

RESULTS

After follow-up (median, 43.9 months), renal failure (50% reduction in glomerular filtration rate [GFR] or dialysis) had developed in 13 subjects. The expression levels of renal fibrogenic genes were increased as compared to controls without LN. COL1 correlated with collagen I/III matrix index at baseline. Both high expression of TGFB1 or COL1 tended to predict renal failure by univariate analysis. By multivariate analysis, high ECMI and low GFR were predictive of renal failure. In patients with baseline GFR of 60 mL/min/1.73 m(2) or greater, high renal COL1 expression was an independent (hazard ratio = 4.4, P = .04) predictor of renal failure.

CONCLUSIONS

High renal COL1 expression is a strong predictor of adverse renal outcome in patients with LN and preserved baseline GFR. These findings support larger prospective studies to confirm the benefits of COL1 in identifying patients at high risk of progression to renal disease.

The value of repeat kidney biopsy in quiescent Argentinian lupus nephritis patients

BACKGROUND

The duration of maintenance therapy after induction therapy for lupus nephritis has not been rigorously established. A common practice is to maintain immunosuppression for 1-2 years after complete remission, and longer for partial remission. The present work addresses whether a repeat kidney biopsy might be informative in deciding who should continue immunosuppression after complete or partial remission.

METHODS

The practice in a large Buenos Aires nephrology unit is to repeat a kidney biopsy before finalizing the decision to withdraw or continue immunosuppression. This work reports on a cohort of 25 Hispanic patients that had two or more kidney biopsies, the last occurring after at least 24 months of clinically quiescent disease.

RESULTS

Despite normalization of serum creatinine and reduction of proteinuria to <500 mg/d, 30% of patients still had significant activity at the last biopsy. Conversely, 60% of patients with ongoing proteinuria (500-1000 mg/d), or stable but abnormal serum creatinine, had no activity by biopsy. Univariate association analyses demonstrated that improvement in the activity index (AI) of the last biopsy was associated with choice of induction therapy (cyclophosphamide or mycophenolate), improvement in serum creatinine over the first six months of treatment, and improvement in complement component C4. By multivariate regression analyses, two AI prediction models emerged. Cyclophosphamide plus change in serum creatinine or cyclophosphamide plus change in C4 accounted for 50% of the improvement in AI.

CONCLUSION

These data suggest that a repeat biopsy may be useful in making the decision to withdraw or continue maintenance immunosuppression.

A composite urine biomarker reflects interstitial inflammation in lupus nephritis kidney biopsies

The initial treatment of lupus nephritis is usually based on a renal biopsy. Subsequent disease flares, however, are often treated without the benefit of kidney pathology because repeat biopsies are infrequent. A noninvasive, real-time method to assess renal pathology would be useful to adjust treatment and improve outcome. To develop such a method we collected urine samples at or close to the time of 64 biopsies from 61 patients with lupus nephritis to identify potential biomarkers of tubulointerstitial inflammation and correlated these to biopsy parameters scored by a renal pathologist using a semiquantitative scale. Linear discriminant analysis was used to weight variables and derive composite biomarkers that identified the level of tubulointerstitial inflammation based on urine concentrations of monocyte chemotactic protein-1, hepcidin (a marker of active lupus), and liver fatty acid-binding protein. The discriminant function that described the most accurate composite biomarkers included urine monocyte chemotactic protein-1 and serum creatinine as the independent variables. This composite had sensitivity, specificity, positive predictive value, and negative predictive value of 100, 81, 67, and 100%, respectively. Only 14% of the biopsies were misclassified. Thus, specific renal pathologic lesions can be modeled by composite biomarkers to noninvasively follow and adjust the treatment of lupus nephritis reflecting renal injury.

Long-term outcomes--mycophenolate mofetil treatment for lupus nephritis with addition of tacrolimus for resistant cases

BACKGROUND

Although mycophenolate mofetil (MMF) is being increasingly used to manage lupus nephritis (LN), long-term experience is limited. Despite treatment, a significant proportion of patients will be refractory to this regime.

METHODS

We report, in this observational study, our long-term experience treating 70 patients with biopsy-proven LN, with MMF as continuous induction-maintenance therapy, who were followed up prospectively over a 5-year period. As rescue therapy for MMF-resistant cases, tacrolimus (0.075 mg/kg/day) was added. The study primary end point was complete response (CR). Secondary end points included partial response (PR), treatment failure, relapse and side effects. Predictor factors associated to renal outcome were analysed by Cox regression analysis.

RESULTS

Thirty-six MMF-treated patients (51%) remained in CR, and 23 (33%) failed treatment at last follow-up. Time to treatment failure was associated with persistent hypoalbuminaemia (hazard ratio (HR) = 0.87; 95%CI, 0.81-0.95; P = 0.001), higher proteinuria (HR = 1.29; 95%CI, 1.03-1.62; P = 0.030) and fewer early responses (HR 0.28; 95%CI, 0.10-0.77; P = 0.014). Renal relapse occurred in 24 (34%) patients. Time to flare was associated with persistent anti-dsDNA titres (HR = 1.001; 95%CI, 1.001-1.003; P = 0.005) and younger age at inclusion (HR = 0.36; 95%CI, 0.14-0.90; P = 0.029). Tacrolimus was added to 17 (24%) patients. A significant reduction of proteinuria was already observed at 3 months (P = 0.002). After 2 years follow-up, 12 (70%) of them achieved clinical response (six CR and six PR). Conclusions. MMF is an effective treatment for LN. Combination therapy with tacrolimus is an effective and safe alternative for MMF-resistant patients.

Male gender results in more severe lupus nephritis

Gender may produce different characteristics in the manifestation of systemic lupus erythematosus (SLE). The present study investigated the influence of gender on clinical, laboratory, autoantibodies and histopathological classes of lupus nephritis (LN). As much as 81 patients diagnosed with SLE (ACR criteria) and active nephritis, who underwent renal biopsy between 1999 and 2004, and who had frozen serum samples and clinical data available from the time of biopsy, were selected for this study. The presence of anti-P and antichromatin antibodies was measured using ELISA, and anti-dsDNA was measured using indirect immunofluorescence. All of the renal biopsies were reviewed in a blinded manner by the same expert renal pathologist. The charts were extensively reviewed for demographic and renal features obtained at the time of the biopsy. Of the 81 patients (13.6%), 11 were male SLE patients. Both male and female lupus patients were of similar age and race, and had similar durations of lupus and renal disease. The female patients had more cutaneous (95.7 vs. 45.5%, P = 0.0001) and haematological (52.9 vs. 18.2%, P = 0.04) involvements than the male SLE patients. In addition, the articular data, central nervous system analyses, serositis findings and SLEDAI scores were similar in both experimental groups. Positivity for anti-dsDNA, anti-ribosomal P and antichromatin did not differ between the two groups, and both groups showed similarly low C3 or C4 serum levels. Our analysis indicated that no histopathological class of LN was predominant in both males and females. Interestingly, the serum creatinine levels were higher in the male SLE patients compared to the female SLE group (3.16 +/- 2.49 vs. 1.99 +/- 1.54 mg/dL, P = 0.03), with an increased frequency of high creatinine (81.8 vs. 47.1%, P = 0.04) as well as renal activity index (7.6 +/- 3.5 vs. 4.8 +/- 3.5, P = 0.02). In addition, whilst the mean levels of proteinuria, cylindruria and serum albumin were markedly altered, they were comparable between both lupus men and women. Moreover, the frequencies of dialysis, renal transplantation and death were similar between the two groups. These data suggest that male patients had a more severe LN compared to women diagnosed with this renal abnormality.

Renal interstitial cells, proteinuria and progression of lupus nephritis: new frontiers for old factors

Interstitial cells, inflammatory-immune cells, tubular cells and endothelial cells of the peritubular capillaries have arisen as possible major players of the nephron damage in lupus nephritis. Increased ICAM-1, Von Willebrand factor, soluble endothelial protein C receptors and decreased ADAMS-13 point to a diffuse vascular damage. Albuminuria elicits a rapid generation of hydrogen peroxide in proximal tubular cells along with nuclear factor-kB activation, endothelin-1 and transforming growth factor (TGF-β1) upregulation. TGF-β1 enhances epithelial-to-mesenchymal transdifferentiation. Albuminuria also enhances the expression of macrophage chemotactic protein-1 and macrophage inflammatory protein-1α, thus leading to increased interstitial inflammation. TGF-β1 and thrombospondin-1, a putative activator of TGF-β, induce apoptosis of peritubular capillaries, as well as of glomerular endothelial cells. All these events can be counteracted by hepatocyte growth factor (HGF), which is expressed by the epithelial tubular cells and stimulates the growth of epithelial cells (mitogen), enhances the motility of epithelial cells (motogen), induces renal epithelial tubule regeneration (morphogen) and enhances angiogenesis (angiogen). The balance between TGF-β1 and HGF could be a key to define the prognostic value of kidney histopathology at baseline and during follow-up, in lupus nephritis. Therapeutic strategies aiming at altering the biological balance in the patients are at hand to test and prove the experimental evidences.

Treatment with cyclophosphamide delays the progression of chronic lesions more effectively than does treatment with azathioprine plus methylprednisolone in patients with proliferative lupus nephritis

OBJECTIVE

To analyze the effect of treatment with either pulse cyclophosphamide (CYC) or azathioprine (AZA) combined with methylprednisolone (MP), on serial biopsy results in patients with proliferative lupus nephritis, and to evaluate the predictive value of various histopathologic and clinical parameters with regard to disease outcome.

METHODS

Biopsy specimens from patients with proliferative lupus nephritis, obtained at study entry and after 2 years of therapy, were scored according to a standardized method, and results assessed in relation to disease outcome.

RESULTS

Of the 87 patients originally enrolled, 39 underwent repeat biopsy. These patients were representative of the overall group, both at entry and at 2-year followup. The median activity index changed from 8.0 to 2.7 (no differences between the treatment groups). In the group treated with AZA plus MP (AZA group), the increase in the median chronicity index (from 2.7 to 3.8) was larger than that in the CYC group (from 2.7 to 3.0) (P = 0.050). In multivariate analyses, renal function at enrollment and after 2 years was the best predictor of renal function at the last visit, while none of the histopathologic variables (either at entry or at 2 years) added to this prediction. Comparing patients whose disease transitioned to class II with those who had persistent proliferative lupus nephritis revealed no differences between the treatment groups at either time point, and no clinical differences at 2 years. However, a higher serum creatinine level at entry and greater proteinuria at last visit were characteristic of patients who still had proliferative lupus nephritis at 2 years.

CONCLUSION

These results indicate that, although both CYC and AZA are effective in reducing active lesions in lupus nephritis, progression of chronic lesions is more effectively halted by CYC. Variables assessed by repeat biopsy do not predict clinical outcome.

Clinical outcomes of childhood lupus nephritis: a single center's experience

This study retrospectively reviewed the medical records of children with lupus nephritis (LN) who were treated at Seoul National University Children's Hospital from 1986 to 2005 (mean duration 8.3+/-4.4 years). The records of 77 children (22 male and 55 female) were examined. The mean age at diagnosis was 11.9+/-3.0 years. The initial biopsy results revealed a WHO class IV classification for 60 (88.2%) of 68 biopsy proven cases. Of 77 patients, 67 (87.0%) responded initially to the high-dose corticosteroids with or without additional immunosuppressive therapy. Of the initial responders (67), 30 (44.8%) experienced at least one episode of proteinuric (24) or nephritic (6) flare. Thirteen patients (16.9%) progressed to either chronic renal failure (CRF) or end-stage renal disease (ESRD). Six (7.8%) patients died. A Kaplan-Meier estimate of patient survival and CRF-free survival rate was 95.4% and 88.7% at 5 years and 91.8% and 74.7% at 10 years, respectively. Multivariate analysis for class IV LN revealed male gender (P=0.029), initial hypertension (P=0.001) and absence of remission (P=0.002) to be prognostic factors predicting CRF. Glomerulosclerosis of 10% or more (P=0.005), nephritic flare (P=0.011), and presence of anti-phospholipid antibody (P=0.017) or syndrome (P=0.004) were also found to be independent risk factors for CRF. Cyclophosphamide pulse therapy failed to demonstrate superiority over other combined immunosuppressants used for the treatment of diffuse proliferative LN.

Hepatocyte growth factor and transforming growth factor β1 ratio at baseline can predict early response to cyclophosphamide in systemic lupus erythematosus nephritis

OBJECTIVE

To determine whether the ratio of hepatocyte growth factor (HGF) to transforming growth factor beta1 (TGFbeta1) in systemic lupus erythematosus (SLE) nephritis could be a prognostic factor for response to therapy with cyclophosphamide (CYC) and steroids at 6 months, and to examine whether the molecular ratio of HGF to TGFbeta1 correlates with the activity index (AI) and chronicity index (CI) and has predictive value for remission at the sixth month.

METHODS

Thirty-six SLE patients with new-onset nephritis, 25 of whom were treated with CYC and steroids, entered into a prospective observational cohort trial at a tertiary university referral center. Renal biopsy findings and clinical parameters were recorded for all patients. Histopathologic, clinical, and immunohistochemical data at baseline served to define the predictive value for the outcome at 6 months.

RESULTS

AI and CI at baseline did not distinguish patients who had achieved remission from those who had not achieved remission after receiving CYC plus steroids. HGF and TGFbeta1 were expressed in the tubuli, not in the glomeruli. The CI correlated directly with the TGFbeta1 extension score (TGFbeta1-ES) (r = 0.43, P = 0.008), but correlated indirectly with the HGF intensity score (HGF-IS) (r = -0.39, P = 0.02) and the HGF-ES (r = -0.45, P = 0.006). An HGF-ES:TGFbeta1-ES ratio of >or=1 at baseline distinguished patients who had achieved remission from those who had not achieved remission, with a predictive value of 94%.

CONCLUSION

These findings indicate that baseline expression of renal HGF and TGFbeta1 predicts short-term renal outcome after therapy with CYC and steroids.

Treatment for lupus nephritis: a revisit

The optimal treatment of severe lupus nephritis remains unclear. Regimens consisting of steroid and cyclophosphamide (CYC) appear to be most effective. Infection and gonadal toxicity is a major concern of CYC use in patients of reproductive age. In addition, failure to respond or refractory to CYC treatment may lead to the development of end-stage renal disease. Mycophenolate mofetil (MMF) is a new immunosuppressive agent that selectively inhibits activated lymphocytes and renal mesangial cells. Data from experimental lupus nephritis and controlled studies, albeit small and lacking statistical power, have revealed that MMF is as effective in lupus patients as CYC in the induction of renal remission or as maintenance therapy to reduce renal flare in the short term. The significantly less ovarian toxicity and infection when compared to CYC are particularly attractive for the consideration of MMF in lupus nephritis. The potential of other new therapeutic agents is discussed together with the need for patient recruitment in future trials of lupus nephritis to address the importance of ethnicity as well as histological grading.

Predictors of poor renal outcome in patients with lupus nephritis treated with combined pulses of cyclophosphamide and methylprednisolone

Lupus nephritis remains a major cause of morbidity and mortality in patients with systemic lupus erythematosus. Although the renal prognosis has improved, the optimal therapeutic regime has not been definitively established, and significant challenges remain in the management of disease progression and recurrent renal relapse. We performed a prospective study to evaluate the outcome of 38 patients with severe lupus nephritis treated with standard cyclophosphamide and methylprednisolone pulse therapy, and to determine the variables associated with poor outcome. Five patients developed end-stage renal disease (ESRD) (13%), 10 (26%) developed persistent proteinuria (> 1 g/24h) and 15 (39%) suffered at least one relapse after 8 years of follow-up. A high chronicity index, interstitial fibrosis (P = 0.04), persistent hypertension (P < 0.0001) and hypocomplementaemia (P = 0.002) after treatment were the major variables associated with ESRD. Tubular atrophy (P = 0.01), persistent hypertension (P = 0.0001) and hypocomplementaemia after treatment (P = 0.0281) were associated with persistent proteinuria. Persistence of anti-dsDNA antibodies and hypocomplementaemia after treatment (P = 0.0118) were associated with renal relapse. Our data suggest that the group of patients with persistence of hypocomplementaemia and raised anti-dsDNA antibodies titres are at high risk of renal relapse and may be candidates for continuation of immunosuppressive treatment. Patients with persistent proteinuria alone or a high chronicity index are less likely to respond to immunosuppression, and strict control of the hypertension may be the best approach.

Contrast-enhanced magnetic resonance imaging (MS-325) in a murine model of systemic lupus erythematosus

RATIONALE AND OBJECTIVES

To investigate whether inflammatory activity can be evaluated by MRI with an intravascular compound (MS-325) in Desoxyribonuclease I (Dnase1)-deficient mice, which show classical symptoms of systemic lupus erythematosus.

METHODS

Dnase1-deficient and normal mice (both groups n = 10) underwent MRI with a body weight adapted dose of MS-325 on a 1.5 T whole body scanner equipped with a dedicated surface coil. MR images of the kidneys and the aorta and signal to noise ratios prior and post contrast administration were compared with histopathology in all animals.

RESULTS

Dnase1-knockout mice demonstrated aortic-wall enhancement and inhomogeneous-renal enhancement with significantly higher SNR values corresponding to microscopically proved inflammatory changes (P < 0.05).

CONCLUSION

MS-325-enhanced MRI appears to be a sensitive tool for the detection of renal and vascular involvement in this animal model. In addition, this method may facilitate assessment of therapeutic approaches in patients with SLE in the future.