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

A Comprehensive and Practical Approach to the Management of Lupus Nephritis in the Current Era

Lupus nephritis (LN) is a severe complication of systemic lupus erythematosus (SLE) and is one of the leading causes of morbidity and mortality in patients with SLE. It is estimated that up to 60% of individuals with SLE will develop LN, which can manifest at any stage of a patient's life; however, it commonly emerges early in the course of SLE and tends to exhibit a more aggressive phenotype in men compared to women. Black and Hispanic patients are more likely to progress to kidney failure than white patients. LN is characterized by kidney inflammation and chronic parenchymal damage, leading to impaired kidney function and potential progression to kidney failure. This article provides a comprehensive overview of the epidemiology, pathogenesis, clinical presentation, diagnosis, and management of LN, highlighting the importance of early recognition and treatment of LN to prevent progressive, irreversible kidney damage and improve patient outcomes. Additionally, the article discusses current and emerging therapies for LN, including traditional immunosuppressive agents, biological agents, and novel therapies targeting specific pathways involved in LN pathogenesis, to provide a practical guide for clinicians in properly diagnosing LN and determining a patient-centered treatment plan.

A nomogram predicting the histologic activity of lupus nephritis from clinical parameters

BACKGROUND

The 2021 clinical guidelines of the Kidney Disease: Improving Global Outcomes emphasize the importance of the histological activity index (AI) in the management of lupus nephritis (LN). Patients with LN and a high AI have poor renal outcomes and high rates of nephritic relapse. In this study we constructed prediction models for the AI in LN.

METHODS

The study population comprised 337 patients diagnosed with LN using kidney biopsy. The participants were randomly divided into training and testing cohorts. They were further divided into high-activity (AI >2) and low-activity (AI ≤2) groups. This study developed two clinical prediction models using logistic regression and least absolute shrinkage and selection operator (LASSO) analyses with laboratory test results collected at the time of kidney biopsy. The performance of models was assessed using 5-fold cross-validation and validated in the testing cohort. A nomogram for individual assessment was constructed based on the preferable model.

RESULTS

Multivariate analysis showed that higher mean arterial pressure, lower estimated glomerular filtration rate, lower complement 3 level, higher urinary erythrocytes count and anti-double-stranded DNA seropositivity were independent risk factors for high histologic activity in LN. Both models performed well in the testing cohort regarding the discriminatory ability to identify patients with an AI >2. The average area under the curve of 5-fold cross-validation was 0.855 in the logistic model and 0.896 in the LASSO model. A webtool based on the LASSO model was created for clinicians to enter baseline clinical parameters to produce a probability score of an AI >2.

CONCLUSIONS

The established nomogram provides a quantitative auxiliary tool for distinguishing LN patients with a high AI and helps physicians make clinical decisions in their comprehensive assessment.

Research trends and frontiers in lupus nephritis: a bibliometric analysis from 2012 to 2022

OBJECTIVES

Lupus nephritis is a prevalent renal manifestation of systemic lupus erythematosus (SLE) and represents a significant cause of morbidity and mortality associated with the disease. This study endeavors to undertake a meticulous bibliometric analysis of LN publications to comprehend the research hotspots and future directions.

METHODS

The literature on LN was acquired from the Web of Science Core Collection (WoSCC). Co-occurrence and cooperative relationship analysis of authors, institutions, countries, journals, references and keywords in the publication was performed through CiteSpace, VOSviewer and a bibliometric online analysis platform. The knowledge graphs were created, and clustering and emergence analyses were performed.

RESULTS

According to the search strategy, a total of 2077 publications related to lupus nephritis (LN) have been identified, with China being the largest contributor globally. The Ohio State University emerged as the most prolific institution. Lupus is the most cited and published journal. Jan J Weening and Brad Rovin were the most prolific and cocited authors. The current research focus revolved around the "nirp3 inflammasome," "biomarker," and "voclosporin". "international society," "thrombotic microangiopathy (TMA)," and "pathway" were identified to be future research hotpots by keyword burst analysis.

CONCLUSIONS

This bibliometric analysis summarizes for the first time the progress of LN research (2012-2022), and qualitatively and quantitatively evaluates the bibliometric information of LN research. There has been a steady increase in the scientific literature on LN over the past 11 years, with an average growth rate of 7.27%. In this field, researchers are primarily based in China and the United States. The pathogenic mechanisms, management strategies and prognostic outcomes of LN are acknowledged as prospective research hotspots. Bibliometrically, the research status and trends of LN publications may greatly assist and be a significant reference for future research in the area.

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.

Persistent Isolated C3 Hypocomplementemia as a Strong Predictor of End-Stage Kidney Disease in Lupus Nephritis

Introduction

Proliferative lupus nephritis (LN) progresses to end-stage kidney disease (ESKD) in roughly 10% of the cases despite treatment. Other than achieving <0.8 g/24h proteinuria at 12 months after treatment, early biomarkers predicting ESKD or death are lacking. Recent studies encompassing not only LN have highlighted the central role of the alternative complement pathway (ACP), with or without histological evidence of thrombotic microangiopathy (TMA), as a key promotor of renal death.

Methods

We assessed whether persistent isolated C3 hypocomplementemia (PI-LowC3), that is not accompanied by C4 hypocomplementemia, 6 months after kidney biopsy, is associated with an increased risk of death or ESKD in proliferative LN.

Results

We retrospectively followed-up 197 patients with proliferative LN (51 with PI-LowC3) for a median of 4.5 years (interquartile-range: 1.9-9.0), 11 of whom died and 22 reached ESKD. After adjusting for age, gender, ethnicity, hypertension, mycophenolate, or cyclophosphamide use, PI-LowC3 was associated with a hazard ratio [HR] of the composite outcome ESKD or death of 2.46 (95% confidence interval [CI]: 1.22-4.99, P = 0.012). These results were confirmed even after controlling for time-varying estimated glomerular filtration rate (eGFR) measurements in joint longitudinal-survival multiple regression models. After accounting for the competing risk of death, PI-LowC3 patients showed a strikingly increased risk of ESKD (adjusted HR 3.41, 95% CI: 1.31-8.88, P = 0.012).

Conclusion

Our findings support the use of PI-LowC3 as a low-cost readily available biomarker, allowing clinicians to modify treatment strategies early in the course of disease and offering a rationale for complement blockade trials in this particularly at-risk subgroup of LN patients.

Severe lupus nephritis in the present days

Lupus nephritis (LN) is one of the most frequent and severe organ manifestations of systemic lupus erythematosus (SLE) that is a chronic autoimmune disease. Despite improvement in patient and renal prognosis, the disease continued to be associated with a high rate of end stage kidney disease. Along the last decades, it seems that the epidemiology of LN and its clinical presentation have progressively changed. The forms with renal insufficiency at presentation seem to have progressively reduced in developed countries in favour of more mild clinical presentations with urinary abnormalities only. To this clinical change does not correspond a less severe histological lesions, in fact, the extent of active lesions at kidney biopsy are unchanged, whereas chronic lesions are becoming less frequent and less severe. Meanwhile, new types of severe LN defined by the variable association of demographic, clinical, histological characteristics at diagnosis or during the follow-up are gradually emerging and require attention in assessing the therapy and prognosis. During the last years, randomized controlled trials have reported the efficacy of new drugs in association with standard therapy to improve the rate of short- and medium-term renal response. One of the advantages is that these results were obtained with reduced dosage of corticosteroids whose protracted use is associated with increase of chronic organ damage. Optimization of therapeutical strategies, tailored on the demographic clinical and histological characteristics, with combination of old and new drugs are urgently needed for severe LN.

A new pathological perspective on thrombotic microangiopathy

Thrombotic microangiopathy (TMA) refers to a condition caused by microvascular injury that includes thrombosis, hemolytic anemia, and thrombocytopenia. There are two classic TMAs, hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura, as well as an atypical HUS (aHUS). aHUS includes a broad spectrum of disorders with diverse etiologies and shares clinical manifestations with classic TMA; however, it frequently lacks typical clinical and laboratory findings. These traits can confuse clinicians and pathologists in terms of renal pathologic diagnosis, especially in cases where TMA is associated with other glomerulopathies or hypertensive renal disease. In this review, new paradigms for classifying TMA and the diversity of histopathologic changes including associated renal diseases are discussed. Renal biopsy is an important and useful diagnostic tool for diagnosing TMA and identifying TMA changes in other renal diseases, including hypertension. Adopting the term “TMA features” for TMA-like changes in glomerulus or artery/arteriole in addition to the pathological diagnosis of glomerulopathy would be informative to clinicians for a prompt diagnosis and treatment of aHUS.

Kidney thrombotic microangiopathy in lupus nephritis: Impact on treatment and prognosis

Introduction

Lupus nephritis (LN) may present with thrombotic microangiopathy (TMA) on kidney biopsy, the impact of which on outcomes is unclear. This study examined the prognostic importance of LN with TMA on kidney biopsy, including response to therapy and long-term outcomes.

Methods

We conducted a single-center, retrospective study of all cases of LN with concomitant TMA on kidney biopsy in the Glomerular Disease Collaborative Network database. Controls were individuals with LN without TMA matched to cases based on demographic and clinical variables. Outcomes were remission at 6- and 12-months, end-stage kidney disease (ESKD) and death. Logistic regression and Cox proportional hazards models were used to ascertain the risks for outcomes, with adjustment for serum creatinine and proteinuria.

Results

There were 17 cases and 28 controls. Cases had higher creatinine, higher proteinuria and greater chronicity on biopsy at baseline compared to controls. The rates of remission at 6-months and 12-months were similar between cases and controls (6-months 53.9% vs 46.4%, adjusted OR 2.54, 95% CI 0.48, 13.37; 12-months 53.9% vs 50.0%, adjusted OR 2.95, 95% CI 0.44, 19.78). Cases were at greater risk for ESKD in univariate analysis (HR 3.77; 95% CI 1.24, 11.41) but not when adjusting for serum creatinine and proteinuria (HR 2.20; 95% CI 0.63, 7.71). There was no significant difference in the risk of death between cases and controls.

Conclusion

Lupus nephritis with renal TMA likely responds to therapy similarly to those without TMA; risk for ESKD is not significantly increased, although the influence of renal function and proteinuria in larger samples is needed.

Thrombotic microangiopathy versus class IV lupus nephritis in systemic lupus erythematosus

BACKGROUND

Kidney involvement is common in patients with systemic lupus erythematosus (SLE). This study investigates the clinical and prognostic characteristics of thrombotic microangiopathy (TMA) compared to class IV lupus nephritis in SLE patients.

METHODS

A retrospective review of patients who underwent kidney biopsy, with a primary diagnosis of SLE and TMA between June 2006 and September 2018 was conducted. Those patients were subsequently compared to patients with class IV lupus nephritis between January 2018 and December 2018. Demographics, laboratory, and serological data at the time of biopsy were abstracted.

RESULTS

Among 214 SLE patients records screened, 27 were included in the final analysis. Eight patients had lupus-related TMA without evidence of active lupus nephritis, while 19 patients had class IV lupus nephritis without evidence of TMA. TMA patients had significantly higher lactate dehydrogenase levels (718 ± 499 vs. 264 ± 107.7 U/L, p = 0.009), serum C3 (100.6 ± 39.3 vs. 65.8 ± 27 mg/dL, p = 0.049), white blood cell count (14743.8 ± 7933.3 vs. 5807.9 ± 2053.2 × 10E3/uL, p < 0.001), and total bilirubin (0.8 ± 0.5 vs. 0.3 ± 0.1 mg/dL, p = 0.007) in addition to significantly lower platelet counts (158.4 ± 88.6 vs. 240.3 ± 100.3 × 10E3/uL, p = 0.03), and haptoglobin (68.8 ± 116.1 vs. 166.8 ± 95.4 mg/dL, p = 0.03). After a median follow-up time of 53 weeks, 3 patients with TMA were dialysis-dependent (37.5%), compared with none in class IV lupus nephritis patients (p = 0.002).

CONCLUSIONS

TMA-associated SLE has worse prognosis compared to class IV lupus nephritis. An array of laboratory and pathological findings may be of value in discriminating between those two entities.

Systemic lupus erythematosus multiorgan flare with quiescent serologic markers

Systemic lupus erythematosus (SLE) can affect almost every organ with differing degrees of severity. Typically, SLE activity is associated with hypocomplimentaemia and elevated double-stranded DNA (dsDNA) levels. We describe a case of a severe multiorgan lupus flare including lupus cerebritis, autoimmune haemolytic anaemia, lupus nephritis and lupus myopericarditis with normal complement and dsDNA levels. This highlights the importance of understanding the heterogeneous nature of SLE flares.

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.

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.

Hematological Manifestations among Patients with Rheumatic Diseases

BACKGROUND

Rheumatic diseases have many hematological manifestations. Blood dyscrasias and other hematological abnormalities are sometimes the first sign of rheumatic disease. In addition, novel antirheumatic biological agents may cause cytopenias.

SUMMARY

The aim of this review was to discuss cytopenias caused by systemic lupus erythematosus and antirheumatic drugs, Felty's syndrome in rheumatoid arthritis, and autoimmune hemolytic anemia, thrombosis, and thrombotic microangiopathies related to rheumatological conditions such as catastrophic antiphospholipid syndrome and scleroderma renal crisis. Key Message: The differential diagnosis of various hematological disorders should include rheumatic autoimmune diseases among other causes of blood cell and hemostasis abnormalities. It is crucial that hematologists be aware of these presentations so that they are diagnosed and treated in a timely manner.

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.

Evidences of histologic thrombotic microangiopathy and the impact in renal outcomes of patients with IgA nephropathy

INTRODUCTION

IgA nephropathy (IgAN) is the most common primary glomerulopathy worldwide. According to the Oxford Classification, changes in the kidney vascular compartment are not related with worse outcomes. This paper aims to assess the impact of thrombotic microangiopathy (TMA) in the outcomes of Brazilian patients with IgAN.

MATERIALS AND METHODS

Analysis of clinical data and kidney biopsy findings from patients with IgAN to assess the impact of TMA on renal outcomes.

RESULTS

The majority of the 118 patients included were females (54.3%); mean age of 33 years (25;43); hypertension and hematuria were observed in 67.8% and 89.8%, respectively. Median creatinine: 1.45mg/dL; eGFR: 48.8ml/min/1.73m2; 24-hour proteinuria: 2.01g; low serum C3: 12.5%. Regarding to Oxford Classification: M1: 76.3%; E1: 35.6%; S1: 70.3%; T1/T2: 38.3%; C1/C2: 28.8%. Average follow-up: 65 months. Histologic evidence of TMA were detected in 21 (17.8%) patients and those ones presented more frequently hypertension (100% vs. 61%, p <0.0001), hematuria (100% vs 87.6%, p = 0.0001), worse creatinine levels (3.8 vs. 1.38 mg/dL, p = 0.0001), eGFR (18 vs. 60 ml/min/1.73m2), p = 0.0001), low serum C3 (28.5% vs. 10.4%, p = 0.003), lower hemoglobin levels (10.6 vs. 12.7g/dL, p<0.001) and platelet counts (207,000 vs. 267,000, p = 0.001). Biopsy findings of individuals with TMA revealed only greater proportions of E1 (68% vs. 32%, p = 0.002). Individuals with TMA were followed for less time (7 vs. 65 months, p<0.0001) since they progressed more frequently to chronic kidney disease (CKD) requiring kidney replacement therapy (KRT) (71.4% vs. 21,6%, p<0.0001). Male sex, T1/T2, and TMA were independently associated with progression to CKD-KRT.

CONCLUSIONS

In this study patients with TMA had worse clinical manifestations and outcomes. In terms of histologic evidence, E1 distinguished patients with TMA from other patients. Further studies are necessary to analyze the impact of vascular lesions on IgAN prognosis.

Factors Associated With Rapid Progression to Endstage Kidney Disease in Lupus Nephritis

OBJECTIVE

Lupus nephritis (LN) may lead to endstage kidney disease (ESKD) in 22% of patients over a period of 15 years, with the risk being particularly higher in diffuse proliferative forms. The rate of kidney function decline varies. However, a catastrophic course leading to ESKD within a few years from onset is uncommon. The aim of the present study was to assess the factors associated with rapid progression to ESKD in patients with LN.

METHODS

Patients from the Toronto Lupus Clinic with biopsy-proven LN at presentation and estimated glomerular filtration rate (eGFR) 60 mL/min/1.73 m², who developed ESKD within 3 years were retrieved. Pathology reports were reviewed with particular emphasis on distinct histopathologic features. Demographic, clinical, laboratory, and therapeutic variables were also analyzed.

RESULTS

Ten patients (1.8% of the total LN population) developed ESKD within 3 years of diagnosis. Their mean age was 34.2 ± 7.3 years, mean time to ESKD 19.2 ± 12.4 months, initial eGFR 90.2 ± 24.9 mL/min/1.73 m², proteinuria 2.7 ± 1.04 g/24 h. The median rate of kidney function decline was > 43 mL/min/1.73 m²/year. One patient had LN class III, 5 had LN class IV, 2 had membranous LN (class V), and another 2 had mixed IV/V. Moreover, 2 patients had extensive thrombotic microangiopathy, 1 collapsing glomerulonephritis, and 1 concomitant antiglomerular basement membrane (anti-GBM) nephropathy. Four patients showed no unusual kidney pathology; all of them had severe noncompliance (discontinued all medications to follow alternative treatment).

CONCLUSION

Catastrophic progression to ESKD is uncommon in LN. The major associated factors are poor compliance and distinct histopathologic features such as thrombotic microangiopathy, collapsing glomerulopathy, and concomitant anti-GBM nephropathy.

An Update on the Diagnosis and Management of Lupus Nephritis

PURPOSE OF REVIEW

Update on the diagnosis, treatment, and monitoring of lupus nephritis.

RECENT FINDINGS

The recent criteria enable the earlier classification of lupus nephritis based on kidney biopsy and compatible serology. Treatment of active nephritis includes low-dose intravenous cyclophosphamide or mycophenolate, followed by maintenance immunosuppression. Recent trials have suggested superiority of regimens combining mycophenolate with either calcineurin inhibitor or belimumab, although their long-term benefit/risk ratio has not been determined. Encouraging results with novel anti-CD20 antibodies confirm the effectiveness of B cell depletion. Achievement of low-grade proteinuria (< 700-800 mg/24 h) at 12-month post-induction is linked to favorable long-term outcomes and could be considered in a treat-to-target strategy. Also, repeat kidney biopsy can guide the duration of maintenance immunosuppression. Lupus nephritis has increased cardiovascular disease burden necessitating risk-reduction strategies. An expanding spectrum of therapies coupled with ongoing basic/translational research can lead to individualized medical care and improved outcomes in lupus nephritis.

A nationwide cross-sectional analysis of thrombotic microangiopathy in the Japan Renal Biopsy Registry (J-RBR)

BACKGROUND

There have been only a few large-scale cohort studies that have reviewed accumulated cases of thrombotic microangiopathy (TMA). The aim of this study was to collect and analyze TMA cases based on the renal biopsy, as a nationwide survey in Japan.

METHODS

In this cross-sectional study, large nationwide data from the Japan Renal Biopsy Registry (J-RBR) were used. Among the patients registered in the J-RBR online system from July 2007 to July 2017, TMA cases were extracted and epidemiological data and clinical findings were investigated.

RESULTS

Out of the 38,495 patients enrolled in a period of 10 years, 152 (0.39%) cases had been diagnosed with TMA. The patient age was widely distributed, including 9.2%, 66.4%, and 24.3% for children, adults, and the elderly, respectively. There were various causes of TMA. Among them, hemolytic uremic syndrome (HUS)/thrombotic thrombocytopenic purpura (TTP) (16.4%), connective tissue disease (CTD)-related (17.1%), and drug-induced (16.4%) were frequently observed. The background factors of TMA were different in children and adults. In a comparison between groups consisting of HUS/TTP, CTD-related, and drug-induced, the HUS/TTP group was significantly younger (p = 0.01), and the drug-induced TMA group tended to have a high urinary protein positive rate (p = 0.05). A comparative analysis according to the age group showed significantly higher serum creatinine levels in the elderly (p < 0.01).

CONCLUSION

This is the first report of epidemiological and clinical data of biopsy-proven TMA in Japan. The characteristics of TMA with diversity based on the underlying disease and age group were reported.