Renal vascular lesions as a marker of poor prognosis in patients with lupus nephritis. Gruppo Italiano per lo Studio della Nefrite Lupica (GISNEL)

Renal vascular lesions in childhood-onset lupus nephritis

BACKGROUND

This study aimed to determine the clinical significance of renal vascular lesions (RVLs) in childhood-onset lupus nephritis (cLN).

METHODS

We retrospectively reviewed all children with biopsy-proven cLN between 2004-2020 to evaluate the prevalence of RVLs on kidney biopsy and its associated factors and long-term outcomes. The composite kidney outcome was defined as advanced chronic kidney disease (CKD) stage 3-5, kidney failure and death.

RESULTS

107 biopsies from 84 Chinese patients were analysed. RVLs were observed in 19 patients (22.6%), including non-inflammatory necrotizing vasculopathy (NNV, n = 6), thrombotic microangiopathy (TMA, n = 4), arterial sclerosis (AS, n = 3), concurrent NNV with AS (n = 4), concurrent NNV with TMA (n = 1) and concurrent true renal vasculitis with AS (n = 1). The presence of RVLs was associated with lower estimated glomerular filtration rate (eGFR) (66.9 ± 40.3 vs. 95.6 ± 39.4 ml/min/1.73m2, p = 0.005), haemoglobin level (9.1 ± 1.9 vs. 10.4 ± 1.9 g/dL, p = 0.008) and platelet count (150.1 ± 96.4 vs. 217.2 ± 104.8 × 109/L, p = 0.01). LN classes and activity/chronicity indices were similar. Patients with RVLs had poorer composite kidney outcomes, though not reaching statistical significance (log-rank test, p = 0.06). The presence of NNV was associated with inferior survival free from composite kidney outcome (log-rank test, p = 0.0018), compared to other forms of RVLs and those without RVLs. Univariate analysis revealed NNV (HR 7.08, 95% CI 1.67-30.03) was predictive of composite kidney outcome.

CONCLUSION

RVLs are present in one-fifth of cLN patients and are associated with severe presentation. NNV is associated with worse long-term kidney outcome. Routine evaluation of RVLs is warranted and should be incorporated into future classification criteria.

II Brazilian Society of Rheumatology consensus for lupus nephritis diagnosis and treatment

OBJECTIVE

To develop the second evidence-based Brazilian Society of Rheumatology consensus for diagnosis and treatment of lupus nephritis (LN).

METHODS

Two methodologists and 20 rheumatologists from Lupus Comittee of Brazilian Society of Rheumatology participate in the development of this guideline. Fourteen PICO questions were defined and a systematic review was performed. Eligible randomized controlled trials were analyzed regarding complete renal remission, partial renal remission, serum creatinine, proteinuria, serum creatinine doubling, progression to end-stage renal disease, renal relapse, and severe adverse events (infections and mortality). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to develop these recommendations. Recommendations required ≥82% of agreement among the voting members and were classified as strongly in favor, weakly in favor, conditional, weakly against or strongly against a particular intervention. Other aspects of LN management (diagnosis, general principles of treatment, treatment of comorbidities and refractory cases) were evaluated through literature review and expert opinion.

RESULTS

All SLE patients should undergo creatinine and urinalysis tests to assess renal involvement. Kidney biopsy is considered the gold standard for diagnosing LN but, if it is not available or there is a contraindication to the procedure, therapeutic decisions should be based on clinical and laboratory parameters. Fourteen recommendations were developed. Target Renal response (TRR) was defined as improvement or maintenance of renal function (±10% at baseline of treatment) combined with a decrease in 24-h proteinuria or 24-h UPCR of 25% at 3 months, a decrease of 50% at 6 months, and proteinuria < 0.8 g/24 h at 12 months. Hydroxychloroquine should be prescribed to all SLE patients, except in cases of contraindication. Glucocorticoids should be used at the lowest dose and for the minimal necessary period. In class III or IV (±V), mycophenolate (MMF), cyclophosphamide, MMF plus tacrolimus (TAC), MMF plus belimumab or TAC can be used as induction therapy. For maintenance therapy, MMF or azathioprine (AZA) are the first choice and TAC or cyclosporin or leflunomide can be used in patients who cannot use MMF or AZA. Rituximab can be prescribed in cases of refractory disease. In cases of failure in achieving TRR, it is important to assess adherence, immunosuppressant dosage, adjuvant therapy, comorbidities, and consider biopsy/rebiopsy.

CONCLUSION

This consensus provides evidence-based data to guide LN diagnosis and treatment, supporting the development of public and supplementary health policies in Brazil.

Clinical Evaluation and Management of Thrombotic Microangiopathy

Thrombotic microangiopathy (TMA) refers to a diverse group of diseases that share clinical and histopathologic features. TMA is clinically characterized by microangiopathic hemolytic anemia, consumptive thrombocytopenia, and organ injury that stems from endothelial damage and vascular occlusion. There are several disease states with distinct pathophysiological mechanisms that manifest as TMA. These conditions are associated with significant morbidity and mortality and require urgent recognition and treatment. Thrombotic thrombocytopenic purpura and hemolytic uremic syndrome are traditionally considered to be primary forms of TMA, but TMA more commonly occurs in association with a coexisting condition such as infection, pregnancy, autoimmune disease, or malignant hypertension, among others. Determining the cause of TMA is a diagnostic challenge because of limited availability of disease-specific testing. However, identifying the underlying etiology is imperative as treatment strategies differ. Our understanding of the conditions that cause TMA is evolving. Recent advances have led to improved comprehension of the varying pathogenic mechanisms that drive TMA. Development of targeted therapeutics has resulted in significant improvements in patient outcomes. In this article, we review the pathogenesis and clinical features of the different TMA-causing conditions. We outline a practical approach to diagnosis and management and discuss empiric and disease-specific treatment strategies.

Clinical Research of Lupus Retinopathy: Quantitative Analysis of Retinal Vessels by Optical Coherence Tomography Angiography in Patients with Systemic Lupus Erythematosus

BACKGROUND

Lupus retinopathy, an ocular manifestation of systemic lupus erythematosus (SLE), is the major pathology attributed to retinal vasculopathy. Our study is to analyze the changes in retinal vessels in patients with SLE by optical coherence tomography angiography.

METHODS

A total of 61 SLE patients without obvious retinal manifestation and 71 healthy people were included. The SLE patients were further divided into a lupus nephritis (LN) group and a non-LN group. The changes in central macular thickness (CMT) and the retinal vessel densities were compared between the two groups, and the correlation between retinal vascular changes and disease activity was analyzed.

RESULTS

Compared with healthy control, the CMT and the retinal vascular densities in both superficial and deep retina were decreased significantly in SLE patients. There was no significant difference in retinal vascular densities between LN groups and non-LN groups.

CONCLUSION

The CMT and retinal vessel densities were decreased in SLE patients without clinical manifestations, which might serve as a sensitive biomarker for early changes of lupus retinopathy in SLE patients.

Thrombotic microangiopathy mediates poor prognosis among lupus nephritis via complement lectin and alternative pathway activation

Objective

The pathogenesis of thrombotic microangiopathy (TMA) in lupus nephritis (LN) remains complicated. This study aimed to detect the deposition of complement lectin pathway (LP) and alternative pathway (AP) components in renal tissues, then evaluate the clinicopathological characteristics and risk factors for renal survival between patients with or without TMA in LN cohorts.

Methods

We included 79 patients with biopsy-proven LN-associated TMA and matched the same number of LN patients without TMA as the control group. The deposition of mannose binding lectin (MBL), MBL-associated serine proteases 1/3 (MASP1/3), complement factor B (CFB), complement factor D (CFD), C4d, and von Willebrand factor (VWF) in renal tissue was assessed by immunohistochemistry and immunofluorescence. Besides, co-localization of C5b-9 and CD34 was detected by confocal microscopy.

Results

In our retrospective cohort, the incidence of acute kidney injury (30% vs. 14%, p = 0.013), acute hemodialysis (35% vs. 5%, p < 0.001), and interstitial fibrosis (43% vs. 13%, p < 0.001) is higher in the TMA, compared with the control group. Despite aggressive steroids pulse, plasma exchange, and immunosuppressive therapy among TMA group, they still had significantly inferior 3-year renal survival rates (68% vs. 89%, p = 0.002) than those in the non-TMA group. COX regression analysis identified that TMA (HR 4.807, 95% CI [2.052, 11.263], p < 0.001) is a risk factor in LN. MBL, MASP1/3, CFB, CFD, C4d, and VWF deposited along the glomerulus among LN, while TMA had stronger staining intensity and deposition. The co-localized expression of CD34 and C5b-9 in the endothelial cells was also observed in the renal tissues.

Conclusions

TMA is an independent risk factor for renal survival in LN patients. Moreover, LP and AP activation are involved in the pathogenesis of LN-associated TMA.

Revisiting vasculopathy in lupus nephritis: A renal biopsy evaluation study

Introduction:

The classification of lupus nephritis (LN) on biopsy is essentially focused on morphologic changes in glomeruli. Renal vascular lesions are not addressed in detail in current classifications and are often overlooked. We aimed to determine the prevalence of vascular lesions in LN on biopsies and to compare these with biopsies not showing the vasculopathies.

Methods:

A total of 740 renal biopsies of LN were analysedfor presence of vasculopathies from January 2013 to June 2019. Of these, 527 (71.2%) biopsies showed vascular lesions (vascular group), which were further categorized into known five subtypes according to morphology and immunofluorescence (IF) findings. Remaining 213 (28.8%) biopsies constituted non-vascular group. Clinical, demographic and laboratory parameters were compared between these two groups.

Results:

The mean age was 27.95 ± 9.8 years and 27.0 ± 9.4 years in the vascular and non-vascular groups respectively with higher M:F (1:2 > 1:7) in vascular group. Majority of vasculopathies (257, 48.7%) were found in biopsies with class IV LN. Haematuria (69.8% vs. 20.1%), proteinuria (100% vs. 62%), anemia (48.3% vs. 3.60%) and hypertension (39.8% vs. 8.46%) were common in group I. Uncomplicated vascular immune deposits (426; 80.8%) were the most common vasculopathy and true vasculitis (4;0.8%) was least common. Activity and chronicity indices (7.35 ± 3 and 2.45 ± 1.5, respectively) were significantly higher in the vascular group. Activity index was highest in uncomplicated vascular immune deposits (7.45 ± 2.8) and chronicity index was highest in non-specific sclerotic vascular lesions (2.7 ± 1.6).

Conclusion:

Vascular involvement is common in LN. Uncomplicated vascular immune deposits were common vasculopathies whereas true vasculitis was least common. The morphology and IF both need to be carefully screened for the diagnosis of vasculopathies.

Elevated circulating thrombomodulin levels in systemic lupus erythematosus: a systematic review and meta-analysis

OBJECTIVES

Thrombomodulin (TM) is closely related to the pathogenesis of autoimmune diseases, including systemic lupus erythematosus (SLE). However, current evidence on circulating TM levels in SLE patients is contradictory. We conducted this meta-analysis to more accurately assess circulating TM levels in patients with SLE and lupus nephritis (LN) and to analyze related influencing factors.

METHODS

Systematic search of relevant documents was conducted in PubMed, Embase, and The Cochrane Library databases (up to 28 February 2021). Studies on the comparison of circulating TM between SLE patients and controls were screened and evaluated for inclusion. Random-effects model analysis was applied to calculate the combined standardized mean difference (SMD) with a 95% confidence interval (CI). Heterogeneity was estimated by Q statistics and I2.

RESULTS

A total of 353 articles were identified, 14 provided adequate information for this study finally. The results illustrated that SLE patients had higher TM levels than healthy controls (SMD =0.38, 95% CI: 0.02 to 0.74, p=0.04). Circulating TM levels were increased in patients with active SLE compared to inactive SLE patients (SMD=1.12, 95% CI: 0.03 to 2.20, p=0.04). In addition, circulating TM levels of SLE patients with LN were higher than those without LN (SMD=4.55, 95% CI: 1.97 to 7.12, p=0.001).

CONCLUSIONS

The circulating TM levels in SLE patients are enhanced. In addition, circulating TM levels may be practical in reflecting the disease activity and nephritis involvement of SLE patients.

Lupus Vasculitis: An Overview

Lupus vasculitis (LV) is one of the secondary vasculitides occurring in the setting of systemic lupus erythematosus (SLE) in approximately 50% of patients. It is most commonly associated with small vessels, but medium-sized vessels can also be affected, whereas large vessel involvement is very rare. LV may involve different organ systems and present in a wide variety of clinical manifestations according to the size and site of the vessels involved. LV usually portends a poor prognosis, and a prompt diagnosis is fundamental for a good outcome. The spectrum of involvement ranges from a relatively mild disease affecting small vessels or a single organ to a multiorgan system disease with life-threatening manifestations, such as mesenteric vasculitis, pulmonary hemorrhage, or mononeuritis multiplex. Treatment depends upon the organs involved and the severity of the vasculitis process. In this review, we provide an overview of the different forms of LV, describing their clinical impact and focusing on the available treatment strategies.

High Burden of Premature Arteriosclerosis on Renal Biopsy Results in Incident Lupus Nephritis

OBJECTIVE

Cardiovascular disease (CVD) is accelerated in patients with systemic lupus erythematosus and lupus nephritis (LN). Despite the literature suggesting that renal arteriosclerosis predicts CVD in other glomerulonephritis diseases, arteriosclerosis grading and reporting might be particularly overlooked in LN biopsies. Our objective was to examine the burden of renal arteriosclerosis in LN and to assess whether arteriosclerosis is underreported in LN biopsies.

METHODS

We identified all patients with LN undergoing kidney biopsy between 1994 and 2017 at an academic center. We interpreted LN biopsy reports to classify the Banff categories of absent, mild, moderate, or severe renal arteriosclerosis. The prevalence of renal arteriosclerosis was compared with the prevalence published for age-matched healthy peers, and predictors of arteriosclerosis were examined. We overread biopsies for Banff renal arteriosclerosis grading and compared to pathology reports.

RESULTS

Among 189 incident patients with LN, renal arteriosclerosis prevalence was 2 decades earlier compared to their healthy peers, affecting 40% of patients ages 31-39 years with LN compared to 44% of healthy peers ages 50-59 years. A multivariable analysis showed a 3-fold higher odds of renal arteriosclerosis in patients ages ≥30 years with LN. LN chronicity on biopsy results predicted a 4-fold higher odds of renal arteriosclerosis. The overreads determined that 50% of standard LN biopsy reports missed reporting the presence or absence of renal arteriosclerosis.

CONCLUSION

Renal arteriosclerosis is accelerated by 2 decades in patients with LN compared to their healthy peers and is overlooked by pathologists in half of the routine biopsy reports. We propose incorporating Banff renal arteriosclerosis grading in all LN biopsy reports.

Renal thrombotic microangiopathy associated to worse renal prognosis in Lupus Nephritis

INTRODUCTION

Renal thrombotic microangiopathy (rTMA) is one of many vascular findings in Lupus Nephritis (LN). However, the influence of rTMA on prognosis has not been well established. The objective of this study was to evaluate the clinical and pathological aspects of patients with lupus and rTMA in kidney biopsy.

METHODS

Analysis of medical reports and kidney biopsy of 253 patients with LN, between January 2012 and December 2018.

RESULTS

Among our 253 patients, 43 (17%) showed acute or chronic TMA lesions on kidney histology This group had a significantly lower estimated glomerular filtration rate (eGFR) at the time of biopsy (24.1 vs. 64.15 ml/min/1.73m2, p < 0.001), at 1 year of follow up (28.1 vs. 90.7 ml/min/1.73m2, p < 0.001), and at the end of follow up (25.4 vs. 81.55 ml/min/1.73m2, p < 0.001). More patients in the rTMA group reached the composite endpoint of eGFR < 15 mL/min/1.73m2 or death or dialysis (82.9% vs. 32.9%, p < 0.001). When comparing the classical clinical TMA features, the rTMA group had higher percentages of anemia, thrombocytopenia, low haptoglobin levels, but not higher lactate dehydrogenase (LDH) levels (> 214 U/L). Combining these variables in a definition of clinical TMA, the rTMA group had a statistically higher percentage of clinical TMA (20.9% vs. 4.33%, p = 0.001). As expected, TMA group showed higher systolic blood pressure (SBP) (130 vs 129.5 mmHg, p = 0.01). Concerning histopathological features, rTMA group had significantly higher activity (9.0 vs. 6.0, p = 0.001) and chronicity (4.0 vs. 3.0, p = 0.001) scores, also a higher percentage of patients presented with crescents (76.7% vs. 57.1%, p = 0.012).

CONCLUSIONS

The classical clinical TMA criteria were unable to predict the presence of tissue TMA, suggesting a probably renal-limited TMA that may occur independently of systemic evident factors. Therefore, renal biopsy remains the critical method for diagnosing an important prognostic feature.

Complement Factor I Mutation May Contribute to Development of Thrombotic Microangiopathy in Lupus Nephritis

Objective: Renal thrombotic microangiopathy (TMA) is associated with complement overactivation and poor outcome in patients with lupus nephritis (LN). The role of genetic makeup of complement system in these patients remains to be elucidated. Methods: The clinical and laboratory characteristics of 100 patients with LN during 2010-2017 were retrospectively analyzed. LN patients with renal TMA and condition-matched LN patients without renal TMA were studied. Twenty normal subjects were also enrolled for comparison. Whole exome sequence followed by Sanger sequence was used in our study cohort. Results: Eight patients with renal TMA and eight condition-matched patients were enrolled from 100 LN patients with mean age 11.2 ± 2.0 years. Compared with condition-matched LN patients without renal TMA, LN patients with renal TMA exhibited statistically higher serum urea. Although most patients with renal TMA responded to plasma exchange, they had significantly higher relapse rate of nephritis, lower remission rate, and higher risk of end-stage renal disease and mortality. Compared with patients without renal TMA and normal subjects, those with renal TMA had significantly lower serum complement factor H (CFH) and plasma ADAMTS13 activity. Molecular analysis of all 100 patients with LN uncovered that three patients with renal TMA harbored mutations, two missense and non-sense, on CFI and CFHR2. The non-sense mutation, E302X, on CFI may impair its interaction C3b/CFH complex by loss of the heavy chain of complement factor I on simulation model. Conclusion: In addition to low serum CFH level and plasma ADAMTS13 activity, defects in genes responsible for complement regulatory proteins may contribute to the development of renal TMA in patients with LN.

Clinicopathological features and outcomes of SLE patients with renal injury characterised by thrombotic microangiopathy

OBJECTIVES

Non-immune complex (IC)-mediated renal thrombotic microangiopathy (TMA) has been reported in patients with systemic lupus erythematosus (SLE), but most studies included patients with both renal TMA and IC-mediated lupus nephritis (LN). In this study, the clinicopathological features and outcomes of renal injury characterised by only renal TMA were retrospectively analyzed.

METHODS

Patients with glomerular and/or vascular TMA in the absence of subendothelial or epithelial immune deposits were screened from 2,332 biopsied of SLE patients. The TMA lesions were divided into glomerular, vascular or both. Acute tubular-interstitial injury was semi-quantitatively analyzed. The podocyte foot process effacement (FPE) was measured by electronic microscopy.

RESULTS

Two hundred fifty-seven (11.0%) renal biopsies revealed TMA, among which 237 biopsies showed TMA coexisting with LN, and 20 (0.9%) biopsies had only renal TMA without or with only mesangial immune deposits. All patients manifested with acute kidney injury and haematological disorders. Among them, 11 (55%) required renal replacement therapy, 12 (60%) had nephrotic syndrome and 13 (65.0%) showed microvascular haemolytic anaemia with thrombocytopenia. Seventeen (85%) biopsies revealed both glomerular TMA and vascular TMA, two had only glomerular TMA and one had vascular TMA. Eight (40%) had no glomerular immune deposits and 12 (60%) showed only mesangial immune deposits. The acute tubulointerstitial injury in patients requiring dialysis was more severe than those not needing dialysis ((43.6 ± 24.9) % vs. (21.7 ± 20.1) %, p = 0.047). FPE of podocytes was positively correlated with proteinuria (r² = 0.347, p = 0.006). All patients received high-dose methylprednisolone pulse therapy. Four patients received plasma exchange. The renal function of 11 patients requiring dialysis initially recovered after 16.0 (interquartile range [IQR] 9.0, 30.0) days of treatment. During the follow-up of 58.0 (IQR 36.0, 92.3) months, remission was achieved in 19 (95%) patients; only one patient had no response. No patient died or progressed to end-stage renal disease; six patients (30%) relapsed.

CONCLUSION

Renal TMA, usually accompanying severe renal injury, was not uncommon in SLE patients with renal disease and should be distinguished from immune complex-mediated severe classes of LN. Early intensive immunosuppressive treatment may be associated with a good long-term renal outcome. Key Points • Most previous reports of renal TMA in SLE patients were associated with severe types of immune complex-mediated lupus nephritis; • Renal TMA with glomerular pauci-immune or only mesangial immune deposits was found in SLE patients and clinically presented with severe acute renal injury but good renal outcome; • Renal TMA should be considered as a unique type of SLE-associated renal injury.

Thrombotic Microangiopathy among Hospitalized Patients with Systemic Lupus Erythematosus in the United States

Background: This study aimed to evaluate thrombotic microangiopathy’s (TMA) incidence, risk factors, and impact on outcomes and resource use in hospitalized patients with systemic lupus erythematosus (SLE). Methods: We used the National Inpatient Sample to construct a cohort of hospitalized patients with SLE from 2003–2014. We compared clinical characteristics, in-hospital treatments, outcomes, and resource use between SLE patients with and without TMA. Results: Of 35,745 hospital admissions for SLE, TMA concurrently presented or developed in 188 (0.5%) admissions. Multivariable analysis showed that age ≥ 40 years and Hispanics were significantly associated with decreased risk of TMA, whereas Asian/Pacific Islanders and history of chronic kidney disease were significantly associated with increased risk of TMA. TMA patients required more kidney biopsy, plasmapheresis, mechanical ventilation, and renal replacement therapy. TMA was significantly associated with increased risk of in-hospital mortality and acute conditions including hemoptysis, glomerulonephritis, encephalitis/myelitis/encephalopathy, hemolytic anemia, pneumonia, urinary tract infection, sepsis, ischemic stroke, seizure, and acute kidney injury. The length of hospital stays and hospitalization cost was also significantly higher in SLE with TMA patients. Conclusion: TMA infrequently occurred in less than 1% of patients admitted for SLE, but it was significantly associated with higher morbidity, mortality, and resource use.

Management of Severe Refractory Systemic Lupus Erythematosus: Real-World Experience and Literature Review

Systemic lupus erythematosus (SLE) is a highly heterogeneous disease affecting multiple organs and is characterized by an aberrant immune response. Although the mortality of SLE has decreased significantly since the application of glucocorticoids, severe or refractory SLE can potentially cause irreversible organ damage and contribute to the disease morbidity and mortality. Early recognition of severe SLE or life-threatening conditions is of great challenge to clinicians since the onset symptoms can be rapid and aggressive, involving the visceral organs of the neuropsychiatric, gastrointestinal, hematologic, renal, pulmonary, and cardiovascular systems, etc. Additionally, SLE patients with specific comorbidities and detrimental complications could lead to a clinical dilemma and contribute to poor prognosis. Prompt and adequate treatment for severe refractory SLE is crucial for a better prognosis. However, as evidence from well-designed randomized controlled trials is limited, this review aims to provide real-world evidence based on cohort studies from Peking Union Medical College Hospital, the national tertiary referral center in China, together with the literature, on clinical characteristics, risks and prognostic factors, and treatment strategies for severe and/or refractory SLE.

Severity of Intrarenal Arterial Lesions Can Predict the Clinical Prognosis of Hepatitis B Virus-Associated Glomerulonephritis: A Retrospective Study

Background

Intrarenal arterial lesions (IALs) have been studied in immunoglobulin A nephropathy and lupus nephritis, but this has not been reported in hepatitis B virus-associated glomerulonephritis (HBV-GN). This study aims to investigate the prevalence and the role of IALs in HBV-GN.

Methods

IALs were examined in kidney biopsy specimens from 205 patients with HBV-GN retrospectively. The severity of IALs and tubular interstitial lesions was scored semi-quantitatively. The severity of IALs was divided into 4 groups on the basis of ILA score, which were no IALs (Score 0), mild IALs (Score 1-2), moderate IALs (Score 3-4), and severe IALs (Score 5-10) groups. Survival analysis was performed using the Kaplan-Meier method between the severity of IALs and clinical events (doubling of serum creatinine [SCr], ESRD, and death due to the kidney disease).

Results

Among 205 patients with HBV-GN, 143 (69.8%) had IALs in their kidney biopsy specimens. IALs were mild in 28 (19.6%) patients, moderate in 101 (70.6%) patients, and severe in 14 (9.8%) patients. The severity of IALs was associated with high blood pressure (BP), high SCr, and severe tubulointerstitial injuries. The average follow-up time of these 205 HBV-GN patients was 94.2 ± 47.1 months, in which 46 cases had clinical event. The proportions of clinical events in no IAL, mild IAL, moderate IAL, and severe IAL groups were 9.7, 14.3, 25.7, and 71.4%, respectively. Event-free survival of patient in IAL group was significantly lower than that in the no IAL group (p = 0.000). Multivariate cox regression analysis indicated SCr (1.011, 1.007-1.016), hypertension (1.767, 1.004-3.108), and IAL (2.194, 1.062-4.530) were independent risk factors for clinical events after adjustment for age and gender. Event-free clinical survival in moderate and severe IAL groups was significantly lower than that in the no IAL group (p = 0.0111 and p = 0.0001, respectively). Besides, event-free renal survival in severe IAL group was significantly lower than that in moderate IAL group (p = 0.009). Multivariate cox regression analysis showed that the more severe the IALs, the higher the risk of the clinical event, with a hazard ratio of 2.284 for moderate IALs (1.085-4.907) and 3.315 for severe IALs (1.296-8.482).

Conclusions

Severity of IALs is associated with high BP, reduced renal function, and poor clinical prognosis in HBV-GN patients.

Urinary biomarkers in lupus nephritis

Systemic lupus erythematosus (SLE) is the prototypical autoimmune disease that can affect any organ of the body. Multiple mechanisms may contribute to the pathophysiology of systemic lupus, including failure to remove apoptotic bodies, hyperactivity of self-reactive B and T lymphocytes, abnormal exposure to autoantigens, and increased levels of B-cell stimulatory cytokines. The involvement of the kidney, called lupus nephritis (LN), during the course of the disease affects between 30% and 60% of adult SLE patients, and up to 70% of children. LN is an immune-mediated glomerulonephritis that is a common and serious finding in patients with SLE. Nowadays, renal biopsy is considered the gold standard for classifying LN, besides its degree of activity or chronicity. Nevertheless, renal biopsy lacks the ability to predict which patients will respond to immunosuppressive therapy and is a costly and risky procedure that is not practical in the monitoring of LN because serial repetitions would be necessary. Consequently, many serum and urinary biomarkers have been studied in SLE patients for the complementary study of LN, existing conventional biomarkers like proteinuria, protein/creatinine ratio in spot urine, 24 ​h urine proteinuria, creatinine clearance, among others and non-conventional biomarkers, like Monocyte chemoattractant protein-1 (MCP-1), have been correlated with the histological findings of the different types of LN. In this article, we review the advances in lupus nephritis urinary biomarkers. Such markers ideally should be capable of predicting early sub-clinical flares and could be used to follow response to therapy. In addition, some of these markers have been found to be involved in the pathogenesis of lupus nephritis.

A case of lupus vasculopathy presenting favorable renal outcome

Noninflammatory necrotizing vasculopathy, also referred to as lupus vasculopathy, is not infrequently observed in the pathology of lupus nephritis. It affects vessels causing them to become severely narrowed and occluded by a mechanism involving immune complexes. We experienced a 51-year-old woman with lupus nephritis class IV + V, which was accompanied by lupus vasculopathy. Renal biopsy and light microscopy showed eosinophilic hyaline-like material in the afferent and/or efferent arterioles, which narrowed the lumen, and which were positive for IgG by immunofluorescent analysis. Electron microscopy indicated that amorphous material and endothelial detachment occluded the arterioles. These findings were consistent with those of lupus vasculopathy. We treated the patient with steroids and cyclophosphamide. By the day of discharge, her levels of creatinine and proteinuria had undergone partial remission. Although lupus vasculopathy was implied as a lesion with unfavorable renal prognosis, some recent reports suggest its true renal prognosis is not unfavorable necessarily. Nevertheless, lupus vasculopathy is an important finding in diagnosis in contradiction to other vascular legions in systemic lupus erythematosus. In addition, a standard therapy has also not been established. Therefore, it is important to accumulate cases of lupus vasculopathy to determine its prognosis and develop standard treatments.

Rethinking Lupus Nephritis Classification on a Molecular Level

The International Society of Nephrology/Renal Pathology Society (ISN/RPS) lupus nephritis (LN) classification is under reconsideration, given challenges with inter-rater reliability and resultant inconsistent relationship with treatment response. Integration of molecular classifiers into histologic evaluation can improve diagnostic precision and identify therapeutic targets. This study described the relationship between histological and molecular phenotypes and clinical responses in LN. Renal compartmental mRNA abundance was measured in 54 biopsy specimens from LN patients and correlated to ISN/RPS classification and individual histologic lesions. A subset of transcripts was also evaluated in sequential biopsies of a separate longitudinal cohort of 36 patients with paired samples obtained at the time of flare and at follow up. Unsupervised clustering based on mRNA abundance did not demonstrate a relationship with the (ISN/RPS) classification, nor did univariate statistical analysis. Exploratory analyses suggested a correlation with individual histologic lesions. Glomerular FN1 (fibronectin), SPP1 (secreted phosphoprotein 1), and LGALS3 (galectin 3) abundance correlated with disease activity and changed following treatment. Exploratory analyses suggested relationships between specific transcripts and individual histologic lesions, with the important representation of interferon-regulated genes. Our findings suggested that the current LN classification could be refined by the inclusion of molecular descriptors. Combining molecular and pathologic kidney biopsy phenotypes may hold promise to better classify disease and identify actionable treatment targets and merits further exploration in larger cohorts.

Clinical Outcomes and Clinico-pathological Correlations in Lupus Nephritis with Kidney Biopsy Showing Thrombotic Microangiopathy

Objective.

Renal thrombotic microangiopathy (TMA) is an uncommon pathological finding in lupus nephritis (LN), and its clinical significance remains to be defined.

Methods.

Twenty-four patients with lupus nephritis (LN) and renal TMA were selected from a retrospective review of 677 biopsy-proven LN patients, and compared with 48 LN controls without TMA (1:2 ratio) matched according to demographics and treatments.

Results.

Renal TMA was noted in 3.5% of kidney biopsies of LN. TMA was associated with a higher prevalence of anti-Ro (45.8% vs 18.8%; p = 0.016), higher Systemic Lupus Erythematosus Disease Activity Index scores (21.4 ± 8.5 vs 10.8 ± 2.3; p < 0.001), lower estimated glomerular filtration rate (eGFR; 16.8 ± 11.7 ml/min vs 77.8 ± 28.6 ml/min; p < 0.001), and a higher percentage of patients who required dialysis (37.5% vs 2.1%; p < 0.001) at the time of kidney biopsy. Activity and chronicity indices [median (range)] were higher in the TMA group [11 (2–19) and 3 (1–8), respectively, compared with 7 (0–15) and 1 (0–3) in controls; p = 0.004 and p < 0.001; respectively]. Patients with TMA showed inferior 5-year renal survival and higher incidence of chronic kidney disease at last followup (70% and 66.6%, respectively, compared with 95% and 29.2% in controls; p = 0.023 and 0.002, respectively). The TMA group also showed lower median eGFR compared with controls [50.1 (IQR 7–132) ml/min vs 85.0 (IQR 12–147) ml/min; p = 0.003]. Five-year patient survival rate was similar between the 2 groups (87% and 98% in TMA and control group, respectively; p = 0.127).

Conclusion.

TMA in kidney biopsy was associated with more severe clinical and histological activity, and significantly inferior longterm renal outcome in LN.

Systemic Lupus Erythematosus with Linear IgA Bullous Dermatosis and Renal Vascular Lesions: An Extremely Rare Association

We report a rare case of systemic lupus erythematosus presenting initially with cutaneous manifestations of linear IgA bullous dermatosis. Later the patient developed renal abnormalities due to thrombotic microangiopathy and lupus nephritis with inflammatory necrotizing vasculitis. Paucity of immune deposits was observed on Immunofluorescence. This association of SLE with these cutaneous and renal lesions is rarely reported in the literature.

Thrombotic Microangiopathies with Rheumatologic Involvement

Thrombotic microangiopathies are heterogeneous disorders characterized by microangiopathic hemolytic anemia with thrombocytopenia and renal injury. There are a variety of causes, including metabolic disorders, infections, medications, complement disorders, pregnancy, malignancy, and autoimmune disorders. This review focuses on renal thrombotic microangiopathy in the setting of rheumatologic diseases. Systemic lupus erythematosus is the most common autoimmune disease associated with thrombotic microangiopathy. Other etiologies include scleroderma renal crisis and antiphospholipid antibody syndrome, which can be primary or secondary to autoimmune diseases including systemic lupus erythematosus. There have also been case reports of thrombotic microangiopathy in the setting of rheumatoid arthritis and dermatomyositis.

Microthrombotic Renal Vascular Lesions Are Associated to Increased Renal Inflammatory Infiltration in Murine Lupus Nephritis

Background: Vascular microthrombotic lesions in lupus nephritis with or without antiphospholipid antibodies may relate to worse renal outcomes. Whether microthrombotic lesions are a consequence of renal inflammation or independently contribute to renal damage is unclear. Our aim was to investigate the relationship between microthrombotic renal vascular lesions and nephritis progression in MRL/lpr mice. Methods: MRL/lpr mice were analyzed for the presence of renal microvascular, glomerular and tubulointerstitial lesions and the effect of anti-aggregation (aspirin or clopidogrel) and dexamethasone on renal clinical and pathological manifestations was evaluated. Intravascular platelet aggregates (CD41), peri- (F4/80), and intraglomerular (Mac-2) macrophage infiltration, and C3 deposition were quantified by immunohistochemistry. Renal function was assessed by measuring proteinuria, and serum levels of creatinine and albumin. Anti-dsDNA and anti-cardiolipin antibodies, and thromboxane B2 levels were quantified by ELISA. Results: Frequency of microthrombotic renal lesions in MRL/lpr mice was high and was associated with immune-mediated renal damage. Proteinuria positively correlated with glomerular macrophage infiltration and was higher in mice with proliferative glomerular lesions. All mice had detectable anti-dsDNA and anti-cardiolipin IgG, regardless the presence of microthrombosis. Proteinuria and glomerular macrophage infiltration were significantly reduced in all treatment groups. Dexamethasone and platelet anti-aggregation similarly reduced glomerular damage and inflammation, but only platelet anti-aggregation significantly reduced anti-cardiolipin antibodies, renal complement deposition and thromboxane B2 levels. Conclusions: Platelet anti-aggregation reduced renal inflammatory damage, renal complement deposition, anti-cardiolipin antibodies, and thromboxane B2 levels and in MRL/lpr mice, suggesting that platelet activation has a pathogenic effect on immune-mediated nephritis. Our results point to MRL/lpr mice with lupus nephritis as an appropriate model to analyze the potential impact of anti-thrombotic intervention on renal inflammation.

Renal involvement in antiphospholipid syndrome

This is a review of scientific publications on renal involvement in antiphospholipid syndrome (APS), with focus on clinical and histopathological findings and treatment. A search for English-language articles on renal involvement in APS covering the period 1980-2017 was conducted in Medline/PubMed and Scopus databases using the MeSH terms "antiphospholipid syndrome", "antiphospholipid antibodies", "glomerulonephritis" and "thrombotic microangiopathy" (TMA). APS nephropathy is primarily the result of thromboses in renal arteries or veins, intraparenchymatous arteries and glomerular capillaries. On histology, APS nephropathy is characterized by TMA, but chronic vaso-occlusive lesions are also commonly observed (fibrous intimal hyperplasia, focal cortical atrophy, fibrous occlusions of arteries). Anticardiolipin and lupus anticoagulant are the most prevalent antibodies in patients with APS nephropathy. The spectrum of renal manifestations includes renal vein thrombosis, renal artery thrombosis/stenosis, TMA, increased allograft vascular thrombosis and malignant hypertension. Anticoagulation is the standard treatment of thrombotic events. In systemic lupus erythematosus (SLE) patients with antiphospholipid antibodies (aPL), kidney failure due to SLE nephritis (immune-complex disease) should be clearly distinguished from kidney failure due to APS-related TMA. In such cases, renal biopsy is mandatory. SLE nephritis requires immunosuppressive therapy, whereas APS nephropathy is usually treated with anticoagulants. Recently, eculizumab and sirolimus have been proposed as a rescue therapy. Based on our review, APS nephropathy appears to be a distinct clinical condition. TMA is a characteristic histopathological finding in APS and is strongly associated with the presence of aPL. This has important therapeutic implications and allows distinguishing APS nephropathy from lupus nephritis.

Use of eculizumab in a systemic lupus erythemathosus patient presenting thrombotic microangiopathy and heterozygous deletion in CFHR1-CFHR3. A case report and systematic review

The association of thrombotic microangiopathy (TMA) with systemic lupus erythematosus (SLE) has been described in 0.5 to 10% of cases, and patients present worse outcome. TMA is described as the association of microangiopathic hemolytic anemia, thrombocytopenia, and an organ injury, frequently the kidney. This study describes a successful case of use of eculizumab in a patient with SLE and TMA refractory to standard therapy, and provides a literature review. Case description and search in PubMed and MEDLINE using systemic lupus erythemathous and/or antiphospholipid syndrome (APS) and eculizumab retrieved 15 case reports. Eighteen-year-old female presented acute renal failure and TMA and was diagnosed with SLE. Steroids and IV cyclophosphamide were started together with plasma exchange. After 55 days, she still persisted with microangiopathic anemia, thrombocytopenia, and anuria, and eculizumab was introduced. She had rapid improvement in hematological parameters, and dialysis was discontinued 25 days after the first dose. Genetic analysis showed large heterozygous deletion encompassing the entire CFHR1 and CFHR3, a finding previously associated with patients presenting atypical hemolytic-uremic syndrome (aHUS). Twenty patients who received eculizumab with SLE and/or APS have been published to date: 11 were female and mean age at presentation was 31 years. Seven out of the 20 patients presented only SLE, 5 patients only APS and 8 patients both SLE and APS. Eighteen patients underwent plasma exchange, with a mean of 20 (4-120) sessions per patient. Thirteen patients received rituximab. Hematological response was evident in 100% and kidney recovery in 85% of patients. The terminal complement blockade with eculizumab is an optional treatment for patients with SLE and/or APS presenting TMA and refractory to current immunosuppression therapies. Genetic testing may help recognize patients with aHUS and SLE/APS and therefore help to determine length of treatment with eculizumab.

Renal Thrombotic Microangiopathy in Proliferative Lupus Nephritis: Risk Factors and Clinical Outcomes: A Case-Control Study

BACKGROUND

Renal thrombotic microangiopathy (TMA) may be associated with lupus nephritis. Its relationship to other disease factors and its specific effect on prognosis are not precisely known. Evidence regarding these aspects is controversial, and information focusing on kidney-limited TMA in systemic lupus erythematosus (SLE) patients is scarce.

OBJECTIVES

The aims of this study were to identify risk factors for renal TMA in patients with lupus nephritis and to determine its impact on clinical outcomes.

METHODS

A case-control study was performed. We studied 245 renal biopsies from SLE patients. We included patients with renal TMA, as well as control subjects adjusted for glomerulonephritis class, estimated glomerular filtration rate, activity and chronicity indices, and follow-up time. Serological and clinical features were measured at the time of the biopsy and during follow-up.

RESULTS

Twenty-three patients with renal TMA and 21 control subjects were included. There were no differences in Systemic Lupus Erythematosus Disease Activity Index score, end-stage renal disease, or mortality between groups during follow-up. After multivariate analysis, lymphopenia (odds ratio, 10.69; 95% CI, 1.35-84.74) and anti-Ro antibody positivity (odds ratio, 8.96; 95% CI, 1.49-53.57) remained significantly associated with renal TMA.

CONCLUSIONS

Lymphopenia and anti-Ro positivity are independent risk factors for renal TMA in SLE patients. This increased risk could be a consequence of the potential role of these factors in endothelial dysfunction and damage. Outcomes were similar for patients with the same estimated glomerular filtration rate and biopsy characteristics, regardless of the presence of TMA.

Necrotizing Polyarteritis Nodosa-like Vasculitis in a Child with Systemic Lupus Erythematosus

A 10-year-old child presented with prolonged fever, lymphadenopathy, weight loss, oral ulcers, alopecia and parotitis. She later developed arterial thrombosis, poly-serositis, nephritis, myocarditis, sacro-ilitis, autoimmune hemolytic anemia and refractory thrombocytopenia. Though anti-dsDNA was negative, she was diagnosed to have systemic lupus erythematosus (SLE). Terminally, she had pulmonary symptoms and succumbed to her illness. The autopsy showed lupus nephritis-Class II, polyserositis, myocarditis, inflammatory myositis, immune mediated vasculitis involving renal, coronary, pancreatic, adrenal, dermal and intramuscular arteries, and pulmonary hemorrhages and edema.

Prognostic significance of renal vascular pathology in lupus nephritis

We performed a retrospective cohort analysis to define the prognostic significance of vascular lesions documented in renal biopsies of lupus nephritis patients. A total of 429 patients were segregated into five groups: (1) no vascular lesions (NVL), (2) arterial sclerosis (AS), (3) non-inflammatory necrotizing vasculitis (NNV), (4) thrombotic microangiopathy (TMA), and (5) true renal vasculitis (TRV). Renal outcomes were analyzed by Cox regression models, and correlations between vascular lesions and activity/chronicity scores were determined by Spearman's coefficients. A total of 200 (46.6%) had NVL, 189 (44.0%) AS, six NNV (1.4%), 23 (5.4%) TMA, and 11 (2.6%) TRV. Patients with NVL were younger, with higher renal function; patients with TMA and TRV had lower renal function and higher arterial pressure at baseline. Antiphospholipid syndrome and positive lupus anticoagulant were more frequently observed in the TMA group. Five-year renal survival was 83% for NVL, 63% for AS, 67% for NNV, 31% for TMA, and 33% for TRV. NNV and TRV were significantly correlated with activity scores, while AS and chronic TMA were correlated with chronicity scores. Renal vascular lesions are associated with renal outcomes but do not behave as independent factors. The addition of vascular lesions to currently used scores should be further explored.

Efficacy of Intravenous Cyclophosphamide Pulse Therapy for P-Glycoprotein-expressing B Cell-associated Active True Renal Lupus Vasculitis in Lupus Nephritis

True renal lupus vasculitis (TRLV), a vascular lesion usually associated with proliferative lupus nephritis (LN), is resistant to conventional treatments. The expression of P-glycoprotein (P-gp) on activated lymphocytes causes drug resistance. We herein report a patient with TRLV, minimal change LN, overexpression of P-gp on peripheral B cells, and accumulation of P-gp⁺ B cells at the site of TRLV. High-dose corticosteroids combined with intravenous cyclophosphamide pulse therapy resulted in clinical remission and the long-term normal renal function.

Phosphocalcic Markers and Calcification Propensity for Assessment of Interstitial Fibrosis and Vascular Lesions in Kidney Allograft Recipients

Renal interstitial fibrosis and arterial lesions predict loss of function in chronic kidney disease. Noninvasive estimation of interstitial fibrosis and vascular lesions is currently not available. The aim of the study was to determine whether phosphocalcic markers are associated with, and can predict, renal chronic histological changes. We included 129 kidney allograft recipients with an available transplant biopsy in a retrospective study. We analyzed the associations and predictive values of phosphocalcic markers and serum calcification propensity (T50) for chronic histological changes (interstitial fibrosis and vascular lesions). PTH, T50 and vitamin D levels were independently associated to interstitial fibrosis. PTH elevation was associated with increasing interstitial fibrosis severity (r = 0.29, p = 0.001), while T50 and vitamin D were protective (r = -0.20, p = 0.025 and r = -0.23, p = 0.009 respectively). On the contrary, fibroblast growth factor 23 (FGF23) and Klotho correlated only modestly with interstitial fibrosis (p = 0.045) whereas calcium and phosphate did not. PTH, vitamin D and T50 were predictors of extensive fibrosis (AUC: 0.73, 0.72 and 0.68 respectively), but did not add to renal function prediction. PTH, FGF23 and T50 were modestly predictive of low fibrosis (AUC: 0.63, 0.63 and 0.61) but did not add to renal function prediction. T50 decreased with increasing arterial lesions (r = -0.21, p = 0.038). The discriminative performance of T50 in predicting significant vascular lesions was modest (AUC 0.61). In summary, we demonstrated that PTH, vitamin D and T50 are associated to interstitial fibrosis and vascular lesions in kidney allograft recipients independently of renal function. Despite these associations, mineral metabolism indices do not show superiority or additive value to fibrosis prediction by eGFR and proteinuria in kidney allograft recipients, except for vascular lesions where T50 could be of relevance.

Atypical hemolytic uremic syndrome in the setting of complement-amplifying conditions: case reports and a review of the evidence for treatment with eculizumab

Atypical hemolytic uremic syndrome (aHUS) is a rare, genetic, progressive, life-threatening form of thrombotic microangiopathy (TMA) predominantly caused by dysregulation of the alternative pathway of the complement system. Complement-amplifying conditions (CACs), including pregnancy complications [preeclampsia, HELLP (hemolysis, elevated liver enzymes, low platelet count) syndrome], malignant hypertension, autoimmune diseases, transplantation, and others, are associated with the onset of TMA in up to 69 % of cases of aHUS. CACs activate the alternative pathway of complement and may be comorbid with aHUS or may unmask a previously undiagnosed case. In this review, three case reports are presented illustrating the onset and diagnosis of aHUS in the setting of different CACs (pregnancy complications, malignant hypertension, renal transplantation). The report also reviews the evidence for a variety of CACs, including those mentioned above as well as infections and drug-induced TMA, and the overlap with aHUS. Finally, we introduce an algorithm for diagnosis and treatment of aHUS in the setting of CACs. If TMA persists despite initial management for the specific CAC, aHUS should be considered. The terminal complement inhibitor eculizumab should be initiated for all patients with confirmed diagnosis of aHUS, with or without a comorbid CAC.

Relation of peritubular capillary features to class of lupus nephritis

Background

Experimental studies have linked peritubular capillary (PTC) loss with progression of chronic kidney disease. Minimal information on PTC in lupus nephritis (LN) has been reported. We therefore evaluated the PTC area in different classes of LN and determined if specific clinical characteristics correlated with PTC changes.

Methods

Renal biopsies of 253 subjects with LN (categorized using the ISN/RPS 2003 classification) and 13 normal renal donors (the controls) were retrospectively evaluated for PTC morphology by staining for CD31 with immunohistochemistry method. The percent positive area of PTC (% PTC) was correlated with serum and urinary measures of renal function and renal pathology.

Results

Significant PTC loss was observed in all classes of LN compared to controls. The % PTC area was highest in controls (7.64±1.48 %) with levels of 1.95±1.50, 4.16±3.85, 4.19±4.45, 5.02±1.79, and 4.45±3.75 in classes II, III, IV, IV combined with V and V, respectively (all p values < 0.05). The lowest PTC density was observed in class II LN, but this may be because some cases with worse classes of LN showed increased PTC density due to abnormally dilated capillaries associated with acute inflammation and angiogenesis. %PTC was increased in those with hematuria (5.8±5.2 vs. 3.6±3.4 %, red blood cells 3-10 vs. < 3 cells/high power field, p < 0.05) and was reduced in those with a moderately declined renal function (3.29±3.40 vs. 4.42±4.12, eGFR 15-59 vs. ≥ 60 ml/min/1.73 m2, p < 0.05). Nephrotic-range proteinuria also trended to be associated with lower PTC density although it did not reach statistical significance (3.1±2.6 vs. 4.9±4.5, p= 0.067).

Conclusions

LN is associated with PTC loss and the severity correlates with reduced renal function. Further studies are needed to investigate whether a loss of PTC can predict long term renal outcomes in LN.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0388-2) contains supplementary material, which is available to authorized users.

Lupus nephritis: When and how often to biopsy and what does it mean?

Renal disease is a frequent complication of SLE which can lead to significant illness and even death. Today, a baseline renal biopsy is highly recommended for all subjects with evidence of lupus nephritis. Biopsy allows the clinician to recognize and classify different forms of autoimmune lupus glomerulonephritis, and to detect other glomerular diseases with variable pathogenesis which are not directly related to autoimmune reactivity, such as lupus podocytopathy. Moreover, not only glomerular diseases, but other severe forms of renal involvement, such as tubulo-interstitial nephritis or thrombotic microangiopathy may be detected by biopsy in lupus patients. Thus, an accurate definition of the nature and severity of renal involvement is mandatory to assess the possible risk of progression and to establish an appropriate treatment. The indications to repeat biopsy are more controversial. Some physicians recommend protocol biopsies to recognize the possible transformation from one class to another one, or to identify silent progression of renal disease, others feel that good clinical monitoring is sufficient to assess prognosis and to make therapeutic decisions. At any rate, although any decision should always be taken by considering the clinical conditions of the patient, there are no doubts that repeat renal biopsy may represent a useful tool in difficult cases to evaluate the response to therapy, to modulate the intensity of treatment, and to predict the long-term renal outcome both in quiescent lupus and in flares of activity.

Renal involvement in primary antiphospholipid syndrome

Antiphospholipid syndrome is an autoimmune disorder characterized by recurrent venous or arterial thrombosis and/or pregnancy-related problems associated with persistently elevated levels of antiphospholipid antibodies. The kidney is a major target organ in both primary and secondary antiphospholipid syndrome. This review describes several aspects of the renal involvement in the primary form of the syndrome, in particular the histological pattern of the so-called antiphospholipid syndrome nephropathy (APSN). APSN is a vascular nephropathy characterized by small vessel vaso-occlusive lesions associated with fibrous intimal hyperplasia of interlobular arteries, recanalizing thrombi in arteries and arterioles, and focal atrophy, a constellation of morphological lesions suggestive of primary antiphospholipid syndrome.

Characterization of Patients With Lupus Nephritis Included in a Large Cohort From the Spanish Society of Rheumatology Registry of Patients With Systemic Lupus Erythematosus (RELESSER)

The aim of the study was to profile those patients included in the RELESSER registry with histologically proven renal involvement in order to better understand the current state of lupus nephritis (LN) in Spain. RELESSER-TRANS is a multicenter cross-sectional registry with an analytical component. Information was collected from the medical records of patients with systemic lupus erythematosus who were followed at participating rheumatology units. A total of 359 variables including demographic data, clinical manifestations, disease activity, severity, comorbidities, LN outcome, treatments, and mortality were recorded. Only patients with a histological confirmation of LN were included. We performed a descriptive analysis, chi-square or Student's t tests according to the type of variable and its relationship with LN. Odds ratio and confidence intervals were calculated by using simple logistic regression. LN was histologically confirmed in 1092/3575 patients (30.5%). Most patients were female (85.7%), Caucasian (90.2%), and the mean age at LN diagnosis was 28.4 ± 12.7 years. The risk for LN development was higher in men (M/F:47.85/30.91%, P < 0.001), in younger individuals (P < 0.001), and in Hispanics (P = 0.03). Complete response to treatment was achieved in 68.3% of patients; 10.35% developed ESRD, which required a kidney transplant in 45% of such cases. The older the patient, the greater was the likelihood of complete response (P < 0.001). Recurrences were associated with persistent lupus activity at the time of the last visit (P < 0.001) and with ESRD (P < 0.001). Thrombotic microangiopathy was a risk factor for ESRD (P = 0.04), as for the necessity of dialysis (P = 0.01) or renal transplantation (P = 0.03). LN itself was a poor prognostic risk factor of mortality (OR 2.4 [1.81-3.22], P < 0.001). Patients receiving antimalarials had a significantly lower risk of developing LN (P < 0.001) and ESRD (P < 0.001), and responded better to specific treatments for LN (P = 0.014). More than two-thirds of the patients with LN from a wide European cohort achieved a complete response to treatment. The presence of positive anti-Sm antibodies was associated with a higher frequency of LN and a decreased rate of complete response to treatment. The use of antimalarials reduced both the risk of developing renal disease and its severity, and contributed to attaining a complete renal response.

Renal Interstitial Arteriosclerotic Lesions in Lupus Nephritis Patients: A Cohort Study from China

Objective

The aim of this study was to evaluate renal arteriosclerotic lesions in patients with lupus nephritis and investigate their associations with clinical and pathological characteristics, especially cardio-vascular features.

Design

A retrospective cohort study.

Participants

Seventy-nine patients with renal biopsy-proven lupus nephritis, diagnosed between January 2000 and June 2008 from Peking University First Hospital.

Results

In clinico-pathological data, patients with arteriosclerosis had higher ratio of hypertension and more severe renal injury indices compared with patients with no renal vascular lesions. More importantly, patients with renal arteriosclerosis had worse cardiac structure and function under transthoracic echocardiographic examination. Patients with renal arteriosclerosis tend to have higher ratios of combined endpoints compared with those of no renal vascular lesions, although the difference didn’t reach statistical meanings (P = 0.104).

Conclusion

Renal arteriosclerotic lesion was common and associated with vascular immune complex deposits in lupus nephritis. It might have a certain degree of association with poor outcomes and cardiovascular events, which needs further explorations.

The Revisited Classification of GN in SLE at 10 Years: Time to Re-Evaluate Histopathologic Lesions

Over 10 years have passed since the latest revision of the histopathologic classification of lupus nephritis. This revision was a significant improvement compared with the previous version, mainly because of clearer and more concise definitions and the elimination of mixed subclasses. Despite these improvements, there are still some difficulties in the classification for lupus nephritis, many of which are in the definitions provided. In this review, we focus on the difficulties surrounding the evaluation of classes III and IV lesions, particularly the definitions of endocapillary and extracapillary proliferation, the use of the terms endocapillary proliferation and hypercellularity, the clinical relevance of segmental and global subdivision in class IV, and the value of distinguishing lesions that indicate activity and chronicity. Vascular and tubulointerstitial lesions are also discussed. Furthermore, we give an overview of the history of the classification to provide background on the origin and development of the definitions in lupus nephritis. The issues raised in this review as well as the suggestions for improvements may assist with a revision of the lupus nephritis classification in the near future.

Renal infarction due to lupus vasculopathy

In the ISN/RPS 2003 classification of lupus nephritis (LN) renal vascular lesions are not mentioned. We present a patient with postpartum lupus vasculopathy. The renal biopsy in our patient showed concentric intimal thickening with narrowed lumen. No inflammatory changes were found. It also revealed immunoglobulin and complement deposition on the wall of the arteriole. These changes indicate lupus vasculopathy. The glomeruli revealed diffuse proliferative glomerulonephritis, with wire loops and cellular crescent in one glomerulus. The patient showed improvement with immunosuppression.

Pathological spectrums and renal prognosis of severe lupus patients with rapidly progressive glomerulonephritis

The objectives of the study were to investigate the pathological features and renal prognosis of severe lupus patients with rapidly progressive glomerulonephritis. One hundred and one cases of biopsy-proven severe LN with rapidly progressive glomerulonephritis (RPGN) were analyzed in this retrospective study. Another 200 severe LN patients without RPGN were randomly enrolled as a control group. Their clinicopathological data and long-term outcome were compared. There were 76 females and 25 males with an average age of 31.9 ± 14.2 years followed for a median period of 4 years. Compared with controls, patients with RPGN had shorter LN duration (p = 0.008), higher level of creatinine (p < 0.001), severe anemia (p = 0.037), heavier hematuria (p < 0.001), severe tubular injury parameters [NAG (p < 0.001), RBP (p < 0.001), C3 (p < 0.001)], higher scores of AI (p = 0.001) and CI (p = 0.004), higher proportions of glomerular sclerosis (0.033) and crescents (p < 0.001), severe tubulointerstitial lesions (p < 0.001) and interstitial inflammation (p < 0.001), lower rate of complete remission (33.9 vs 68.2 %) and higher rate of treatment failure (46.8 vs 7.9 %). The 3-, 5- and 10-year cumulative renal survival rates of RPGN and non-RPGN patients were 65.1 versus 53.9 versus 42.9 and 96.9 versus 94.9 versus 91.7 %, respectively. Multivariate analysis revealed that SCr concentration and the proportion of crescents were the most important risk factors for end-stage renal disease (ESRD) in severe LN with RPGN (p < 0.001). In conclusion, RPGN occurred in 3.6 % of LN and is associated with severe renal manifestations, serious sclerotic and crescentic glomeruli lesions, severe tubulointerstitial inflammation, atrophy and fibrosis, prominent leukocyte infiltration and worse treatment response. Multivariate analysis revealed that SCr concentration and the proportion of crescents were the most important risk factors for ESRD. 57.1 % of severe LN patients with RPGN might progress to ESRD within 10 years.

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 vasculopathy: Diagnostic, pathogenetic and therapeutic considerations

A rare form of vascular disease in systemic lupus erythematosus (SLE), lupus vasculopathy is characterized by necrosis and accumulation of immunoglobulins (IGs) and complements in the wall of arterioles and small arteries resulting in luminal narrowing. Lupus vasculopathy often accompanies lupus nephritis and portends a poor prognosis. Although there is general agreement on the treatment of lupus nephritis, effective treatment strategies for lupus vasculopathy remain to be defined. We report a 20-year-old woman with SLE who presented with generalized tonic-clonic seizure. Her immunosuppressive regimen consisted of mycophenolate mofetil, prednisone and hydroxychloroquine. On physical examination, she was Cushingoid in appearance and hypertensive. Laboratory tests indicated renal disease. Coagulation studies disclosed de novo lupus anticoagulant. Magnetic resonance imaging of the brain demonstrated acute focal cerebral hemorrhage. Echocardiography revealed reduced ejection fraction and severe mitral regurgitation. Despite high-dose glucocorticoids and mycophenolate mofetil, renal function remained poor. Kidney biopsy demonstrated lupus vasculopathy and glomerulonephritis. Plasma exchange therapy and intravenous cyclophosphamide were administered. Over the ensuing four weeks, renal function improved, complement levels increased, autoantibody titers decreased and lupus anticoagulant disappeared. In conclusion, lupus vasculopathy can occur in SLE despite a heavy immunosuppressive regimen. Antiphospholipid antibodies might be involved in the pathogenesis of lupus vasculopathy. Plasma exchange therapy in conjunction with intravenous cyclophosphamide may represent an effective treatment strategy for lupus vasculopathy.

Noninflammatory necrotizing vasculopathy in lupus nephritis: a single-center experience

In this study, we assessed the clinicopathological features of lupus nephritis patients with renal noninflammatory necrotizing vasculopathy (NNV). A total of 142 renal biopsies with lupus nephritis were reviewed, including nine cases presented with NNV and 36 without renal vascular lesions. The comparisons of clinical, laboratory and pathological features, treatments, as well as renal outcome between the two groups were further performed. In comparison with the no renal vascular lesions group, patients with NNV changes had significantly higher proportions of noninfection leukocyturia (p = 0.013) and leukocytopenia (p = 0.042), significantly higher serum creatinine (p = 0.012), lower hemoglobin (p = 0.002) and serum C3 (p < 0.001) levels. Renal pathological activity indices and chronicity indices were significantly higher in the NNV group (p = 0.002 and p = 0.006, respectively) than those in the no vascular lesions group. Regarding renal prognosis, the presence of NNV was not a risk factor for renal outcome (p = 0.327). In conclusion, NNV was not infrequent in renal biopsies of lupus nephritis. It was commonly associated with active clinical status and proliferative glomerular lesions of lupus.

Renal biopsy pathology in a cohort of patients from southwest Sydney with clinically diagnosed systemic lupus erythematosus

PURPOSE

The pathological manifestations in the kidneys in systemic lupus erythematosus (SLE) are commonly known as lupus nephritis. We have studied the pathological changes in renal biopsies from 59 cases of clinically diagnosed SLE obtained over a 15-year period from a racially diverse population in the Sydney metropolitan area. Our aim was to see if there was any regional variation in the morphological changes.

METHODS

Renal biopsy changes were assessed by routine light, immunofluorescence, and electron microscopy. We used the modified 1974 World Health Organization classification of lupus nephritis to classify cases into six classes. Disease severity was assessed by age, sex, and across racial groups, including Caucasian, Asian, Middle Eastern, Mediterranean, Indian subcontinental, South American, and Pacific Islander.

RESULTS

Our analysis showed that cases of lupus nephritis contributed 5.4% of our total renal biopsies examined over a 15-year period. The overall incidence of biopsy-proven cases was 0.49 per 100,000 per year. The ages of our patients ranged from 10 to 79 years, with most below 50 years of age. A female to male ratio was determined to be 4.4:1. There was no relationship to ethnicity, nor was there a relationship between any of these parameters and the class or severity of disease.

CONCLUSION

Renal biopsy with multimodal morphological and immunohistochemical analysis remains the gold standard for diagnosis and determination of the level of disease in lupus nephritis. Based on this approach we have identified an incidence rate for southwest Sydney that is slightly higher but comparable to that found in a similar study from the United Kingdom. We also found that there was no relationship between sex, race, or age and severity of disease.

The spectrum of renal thrombotic microangiopathy in lupus nephritis

INTRODUCTION

Among various lupus renal vascular changes, thrombotic microangiopathy (TMA) presented with the most severe clinical manifestations and high mortality. The pathogenesis of TMA in systemic lupus erythematosus (SLE) was complicated. The aim of this study was to assess clinical manifestations, laboratory characteristics, pathological features and risk factors for clinical outcomes of lupus nephritis patients co-existing with renal TMA in a large cohort in China.

METHODS

Clinical and renal histopathological data of 148 patients with biopsy-proven lupus nephritis were retrospectively analyzed. Serum complement factor H, A Disintegrin and Metalloprotease with Thrombospondin type I repeats 13 (ADAMTS-13) activity, antiphospholipid antibodies and C4d deposition on renal vessels were further detected and analyzed.

RESULTS

In the 148 patients with lupus nephritis, 36 patients were diagnosed as co-existing with renal TMA based on pathological diagnosis. Among the 36 TMA patients, their clinical diagnoses of renal TMA were as followings: 2 patients combining with thrombotic thrombocytopenic purpura-hemolytic uremic syndrome, 2 patients combining with anti-phospholipid syndrome, 2 patients with malignant hypertension, 1 patient with scleroderma and the other 29 patients presenting with isolated renal TMA. Compared with the non-renal TMA group, patients with renal TMA had significantly higher urine protein (7.09±4.64 vs. 4.75±3.13 g/24h, P=0.007) and serum creatinine (159, 86 to 215 vs. 81, 68 to 112 μmol/l, P<0.001), higher scores of total activity indices (AI) (P<0.001), endocapillary hypercellularity (P<0.001), subendothelial hyaline deposits (P=0.003), interstitial inflammation (P=0.005), glomerular leukocyte infiltration (P=0.006), total chronicity indices (CI) (P=0.033), tubular atrophy (P=0.004) and interstitial fibrosis (P=0.018). Patients with renal TMA presented with poorer renal outcome (P=0.005) compared with the non-TMA group. Renal TMA (hazard ratio (HR): 2.772, 95% confidence interval: 1.009 to 7.617, P=0.048) was an independent risk factor for renal outcome in patients with lupus nephritis. The renal outcome was poorer for those with both C4d deposition and decreased serum complement factor H in the TMA group (P=0.007).

CONCLUSIONS

There were various causes of renal TMA in lupus nephritis. Complement over-activation via both classical and alternative pathways might play an important role in the pathogenesis of renal TMA in lupus nephritis.

Inclusion of renal vascular lesions in the 2003 ISN/RPS system for classifying lupus nephritis improves renal outcome predictions

The 2003 International Society of Nephrology/Renal Pathology Society (ISN/RPS) pathological classification system of lupus nephritis specified the importance of vascular damage and indicated this should be included in the diagnostic summary. Few pathological studies of lupus nephritis, however, focus on the patterns of renal vascular involvement. Here we assessed renal vascular lesions in lupus nephritis based on the 2003 ISN/RPS classification system and evaluated their association with clinical and pathological data in a large cohort from a single center in China. Among 341 patients with lupus nephritis, 279 were diagnosed with single or multiple renal vascular lesions that included 253 with vascular immune complex deposits, 82 with atherosclerosis, 60 with thrombotic microangiopathy, 13 with noninflammatory necrotizing vasculopathy, and 2 with true renal vasculitis. Patients with thrombotic microangiopathy had the poorest renal outcome. In multivariate Cox hazard analysis after inclusion of renal vascular lesions, the new chronicity index score became a significantly better independent risk factor for renal outcome (hazard ratio 2.32). Thus, renal vascular lesions are common in lupus nephritis and closely correlate with clinical disease activity and renal outcome. Inclusion of a detailed description of renal vascular lesions in the ISN/RPS classification of lupus nephritis may strengthen its predictive value for renal outcome.

A girl with difficult lupus nephritis: lupus vasculopathy

Lupus vasculopathy (LV) is one of the complications of lupus nephritis. No definite therapy has been recommended for the management of LV, and patient outcomes are variable. We present the case of a 16-year-old girl who recovered from stage V chronic kidney disease due to lupus nephritis with vasculopathy with active treatment including pulse methylprednisolone, cyclophosphamide, rituximab and plasma exchange.