Clinical and laboratory predictors of distinct histopathogical features of lupus nephritis

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.

Kidney Biopsy in Management of Lupus Nephritis: A Case-Based Narrative Review

Kidney involvement in patients with lupus highly increases morbidity and mortality. In recent years, several reports have emphasized the dissociation between clinical and histological findings and highlighted the role of kidney biopsy as an instrument for diagnosis and follow-up of lupus nephritis. The kidney biopsy at initial diagnosis allows an early diagnosis, assessment of activity and chronicity, and detection of nonimmune complex nephritis. A kidney biopsy repeated months after treatment aids in the detection of persistent histological inflammation, which has been linked to the occurrence of future kidney relapses. A kidney biopsy at a relapse detects histological changes including chronic scarring. Finally, a kidney biopsy in patients with a clinical response undergoing maintenance immunosuppression may aid therapy tapering and/or suspension. The evidence supporting the use of a kidney biopsy in different scenarios across the course of lupus nephritis is heterogeneous, with most reports assessing the value for the diagnosis of a first or relapsing flare. In contrast, less evidence suggests additional therapeutic-modifying information derived from repeat posttreatment biopsies and biopsies to evaluate treatment tapering or suspension. In this clinical case-based review, we examine the role of kidney biopsy as a tool to improve clinical outcomes of patients with lupus nephritis.

Artificial intelligence and high-dimensional technologies in the theragnosis of systemic lupus erythematosus

Systemic lupus erythematosus is a complex, systemic autoimmune disease characterised by immune dysregulation. Pathogenesis is multifactorial, contributing to clinical heterogeneity and posing challenges for diagnosis and treatment. Although strides in treatment options have been made in the past 15 years, with the US Food and Drug Administration approval of belimumab in 2011, there are still many patients who have inadequate responses to therapy. A better understanding of underlying disease mechanisms with a holistic and multiparametric approach is required to improve clinical assessment and treatment. This Review discusses the evolution of genomics, epigenomics, transcriptomics, and proteomics in the study of systemic lupus erythematosus and ways to amalgamate these silos of data with a systems-based approach while also discussing ways to strengthen the overall process. These mechanistic insights will facilitate the discovery of functionally relevant biomarkers to guide rational therapeutic selection to improve patient outcomes.

High incidence of proliferative and membranous nephritis in SLE patients with low proteinuria in the Accelerating Medicines Partnership

OBJECTIVE

Delayed detection of LN associates with worse outcomes. There are conflicting recommendations regarding a threshold level of proteinuria at which biopsy will likely yield actionable management. This study addressed the association of urine protein:creatinine ratios (UPCR) with clinical characteristics and investigated the incidence of proliferative and membranous histology in patients with a UPCR between 0.5 and 1.

METHODS

A total of 275 SLE patients (113 first biopsy, 162 repeat) were enrolled in the multicentre multi-ethnic/racial Accelerating Medicines Partnership across 15 US sites at the time of a clinically indicated renal biopsy. Patients were followed for 1 year.

RESULTS

At biopsy, 54 patients had UPCR <1 and 221 had UPCR ≥1. Independent of UPCR or biopsy number, a majority (92%) of patients had class III, IV, V or mixed histology. Moreover, patients with UPCR <1 and class III, IV, V, or mixed had a median activity index of 4.5 and chronicity index of 3, yet 39% of these patients had an inactive sediment. Neither anti-dsDNA nor low complement distinguished class I or II from III, IV, V or mixed in patients with UPCR <1. Of 29 patients with baseline UPCR <1 and class III, IV, V or mixed, 23 (79%) had a UPCR <0.5 at 1 year.

CONCLUSION

In this prospective study, three-quarters of patients with UPCR <1 had histology showing class III, IV, V or mixed with accompanying activity and chronicity despite an inactive sediment or normal serologies. These data support renal biopsy at thresholds lower than a UPCR of 1.

Short- and Long-Term Progression of Kidney Involvement in Systemic Lupus Erythematosus Patients with Low-Grade Proteinuria

BACKGROUND AND OBJECTIVES

Lupus nephritis remains a common cause of morbidity and mortality in systemic lupus erythematosus (SLE). Current guidelines recommend performing a kidney biopsy at a urine protein-creatinine ratio of ≥0.5 g/g. However, cross-sectional studies reported a high prevalence of active histologic lupus nephritis lesions, and even chronic irreversible scarring, in patients with low-grade proteinuria. This study was initiated to assess disease progression in patients with SLE and low-grade proteinuria to identify risk factors for progression to overt proteinuria suggestive of clinical lupus nephritis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Patients with SLE who had an incident urinary protein-creatinine ratio of ≥0.2 and <0.5 g/g without known lupus nephritis were identified from the Einstein Rheumatic Disease Registry. Patients who developed a random urinary protein-creatinine ratio of ≥0.5 g/g with or without biopsy during the follow-up period were defined as "progressors." Patients who progressed to a urinary protein-creatinine ratio of ≥0.5 g/g within 2 years of developing a urinary protein-creatinine ratio of ≥0.2 and <0.5 g/g were defined as "fast progressors," a subgroup expected to benefit most from early biopsies and therapeutic interventions.

RESULTS

Among 151 eligible patients with SLE and low-grade proteinuria at study entry, 76 (50%) progressed to a urinary protein-creatinine ratio of ≥0.5 g/g, of which 44 underwent a clinically indicated biopsy. The median (interquartile range) time from a urinary protein-creatinine ratio of ≥0.2 and <0.5 g/g to progression was 1.2 (0.3-3.0) years. Of the 20 biopsies performed in the first 2 years, 16 specimens showed active, treatable lupus nephritis. Low complement and shorter SLE duration at low-grade proteinuria onset were associated with progression to overt proteinuria across different analyses. Other associated factors included hypertension, diabetes mellitus, younger age, and the presence of hematuria.

CONCLUSIONS

In this longitudinal cohort of patients with SLE and low-grade proteinuria at study entry, over half progressed to a urinary protein-creatinine ratio of ≥0.5 g/g in a short time period.

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

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

Lupus nephritis diagnosis using enhanced moth flame algorithm with support vector machines

Systemic lupus erythematosus is a chronic autoimmune disease that affects the kidney in most patients. Lupus nephritis (LN) is divided into six categories by the International Society of Nephrology/Renal Pathology Society (ISN/RPS). The purpose of this research is to build a framework for discriminating between ISN/RPS pure class V(MLN) and classes III ± V or IV ± V (PLN) using real clinical data. The framework is developed by merging a hybrid stochastic optimizer, moth-flame algorithm (HMFO), with a support vector machine (SVM), dubbed HMFO-SVM. The HMFO is constructed by enhancing the original moth-flame algorithm (MFO) with a bee-foraging learning operator, which guarantees that the algorithm speeds convergence and departs from the local optimum. The HMFO is used to optimize parameters and select features simultaneously for SVM on clinical SLE data. On 23 benchmark tests, the suggested HMFO method is validated. Finally, clinical data from LN patients are analyzed to determine the efficacy of HMFO-SVM over other SVM rivals. The statistical findings indicate that all measures have predictive capabilities and that the suggested HMFO-SVM is more stable for analyzing systemic LN. HMFO-SVM may be used to analyze LN as a feasible computer-assisted technique.

One-third of patients with lupus nephritis classified as complete responders continue to accrue progressive renal damage despite resolution of proteinuria

OBJECTIVE

Treatment response in lupus nephritis (LN) is defined based on proteinuria, yet protocol kidney biopsy studies have shown that patients with lupus can have active nephritis in the absence of proteinuria. Using estimated glomerular filtration rate (eGFR) trajectories, we characterised early chronic kidney disease in LN and examined whether certain patients continue to accrue renal damage despite proteinuric response.

METHODS

We conducted a single-centre study of patients diagnosed with their first episode of biopsy-proven class III, IV, and/or V LN (n=37). For each patient, eGFR trajectory was graphed over 5 years following renal biopsy. Participants were divided into those with progressive eGFR loss (eGFR slope <-5 mL/min/1.73 m2/year) versus those with stable eGFR. Participant demographics, renal biopsy features and response status at 1 year (urine protein to creatinine ratio <500 mg/g) were compared between eGFR trajectory groups.

RESULTS

Overall, 30% (n=11) of participants accrued progressive eGFR loss despite standard of care therapy over the first 5 years following renal biopsy. There were no significant differences in baseline renal biopsy features, medication regimens or comorbidities between eGFR trajectory groups. Resolution of proteinuria at 1 year did not differentiate between groups: 6 of 18 (33%) of complete responders continued to accrue renal damage compared with 5 of 17 (29%) of non-responders. Response status could not be assigned for two participants in the stable eGFR group due to missing clinical information at 1 year.

CONCLUSIONS

We identified an understudied category of patients with LN who accrue progressive renal damage despite apparent response to standard of care therapy. Better definitions and biomarkers of response are needed to improve renal outcomes and trial design.

The lupus nephritis management renaissance

Over the past year, and for the first time ever, the US Food and Drug Administration approved 2 drugs specifically for the treatment of lupus nephritis (LN). As the lupus community works toward understanding how to best use these new therapies, it is also an ideal time to begin to rethink the overall management strategy of LN. In addition to new drugs, this must include how to use kidney biopsies for management and not just diagnosis, how molecular technologies can be applied to interrogate biopsies and how such data can impact management, and how to incorporate LN biomarkers into management paradigms. Herein, we will review new developments in these areas of LN and put them into perspective for disease management now and in the future.

Transverse Myelitis in Systemic Lupus Erythematosus: Clinical Features and Prognostic Factors in a Large Cohort of Latin American Patients

BACKGROUND

Acute transverse myelitis (ATM) is an infrequent but severe complication of systemic lupus erythematosus (SLE). The purpose of study was to describe clinical features and prognostic factors of patients with SLE-related ATM.

METHODS

In this medical records review study, data were collected from 60 patients from 16 centers seen between 1996 and 2017 who met diagnostic criteria for SLE and myelitis as defined by the American College of Rheumatology/Systemic International Collaborating Clinics and the Working Group of the Transverse Myelitis Consortium, respectively. Objective neurological impairment was measured with American Spinal Injury Association Impairment Scale (AIS) and European Database for Multiple Sclerosis Grade Scale (EGS).

RESULTS

Among patients included, 95% (n = 57) were female, and the average age was 31.6 ± 9.6 years. Myelitis developed after diagnosis of SLE in 60% (n = 36). Symmetrical paraparesis with hypoesthesia, flaccidity, sphincter dysfunction, AIS = A/B, and EGS ≥ 8 was the most common presentation. Intravenous methylprednisolone was used in 95% (n = 57), and 78.3% (n = 47) received intravenous cyclophosphamide. Sensory/motor recovery at 6 months was observed in 75% (42 of 56), but only in 16.1% (9 of 56) was complete. Hypoglycorrhachia and EGS ≥ 7 in the nadir were associated with an unfavorable neurological outcome at 6 months (p < 0.05). A relapse rate during follow-up was observed in 30.4% (17 of 56). Hypoglycorrhachia and hypocomplementemia seem to be protective factors for relapse. Intravenous cyclophosphamide was associated with time delay to relapse.

CONCLUSIONS

Systemic lupus erythematosus-related ATM may occur at any time of SLE course, leading to significant disability despite treatment. Relapses are infrequent and intravenous cyclophosphamide seems to delay it. Hypoglycorrhachia, hypocomplementemia, and EGS at nadir are the most important prognostic factors.

Clinical and Genetic Risk Factors Associated With the Presence of Lupus Nephritis

Objective

To elucidate whether clinical features and the weighted genetic risk score (wGRS) were associated with the presence of lupus nephritis (LN).

Methods

We retrospectively divided patients with systemic lupus erythematosus (SLE, n=1,078) into biopsy-proven LN (n=507) and non-LN groups (non-LN, n=571) Baseline clinical features, serologic markers, and the wGRS were collected The wGRS was calculated from 112 non-human leukocyte antigen (non-HLA) loci and HLA-DRβ1 amino acid haplotypes for SLE Associations among clinical features, wGRS, and the presence of LN were identified.

Results

In the multivariate analysis, patients with LN were younger at diagnosis (odds ratio [OR]=0.97, p<0.001), had more pleuritis (OR=2.44, p<0.001) and pericarditis (OR=1.62, p=0.029), had a higher detection rate of anti-double stranded deoxyribonucleic acid (anti-dsDNA antibodies, OR=2.22, p<0.001), anti-Smith antibodies (anti-Sm antibodies, OR=1.70, p=0.002), low level of complement (OR=1.37, p=0.043) and absence of antiphospholipid antibodies (aPL antibodies, OR=1.60, p=0.002), and had higher wGRS (OR=1.16, p=0.012) Mediation analysis suggested that anti-Sm antibodies and low complement could be mediators in the relationship between high wGRS and the presence of LN.

Conclusion

Onset age, pleuritis, pericarditis, several serologic markers, and wGRS were associated with the presence of LN Anti-Sm antibodies and low complement appeared to mediate the indirect relationship between wGRS and the presence of LN.

Evolving fuzzy k-nearest neighbors using an enhanced sine cosine algorithm: Case study of lupus nephritis

Because of its simplicity and effectiveness, fuzzy K-nearest neighbors (FKNN) is widely used in literature. The parameters have an essential impact on the performance of FKNN. Hence, the parameters need to be attuned to suit different problems. Also, choosing more representative features can enhance the performance of FKNN. This research proposes an improved optimization technique based on the sine cosine algorithm (LSCA), which introduces a linear population size reduction mechanism for enhancing the original algorithm's performance. Moreover, we developed an FKNN model based on the LSCA, it simultaneously performs feature selection and parameter optimization. Firstly, the search performance of LSCA is verified on the IEEE CEC2017 benchmark test function compared to the classical and improved algorithms. Secondly, the validity of the LSCA-FKNN model is verified on three medical datasets. Finally, we used the proposed LSCA-FKNN to predict lupus nephritis classes, and the model showed competitive results. The paper will be supported by an online web service for any question at https://aliasgharheidari.com.

Urinary Peptides as Potential Non-Invasive Biomarkers for Lupus Nephritis: Results of the Peptidu-LUP Study

Background: Lupus nephritis (LN) is a severe manifestation of Systemic Lupus Erythematosus (SLE). The therapeutic strategy relies on kidney biopsy (KB) results. We tested whether urinary peptidome analysis could non-invasively differentiate active from non-active LN. Design: Urinary samples were collected from 93 patients (55 with active LN and 38 with non-active LN), forming a discovery (n = 42) and an independent validation (n = 51) cohort. Clinical characteristics were collected at inclusion and prospectively for 24 months. The urinary peptidome was analyzed by capillary-electrophoresis coupled to mass-spectrometry, comparing active LN to non-active LN, and assessing chronic lesions and response to therapy. The value of previously validated prognostic (CKD273) and differential diagnostic (LN172) signatures was evaluated. Results: Urinary peptides could not discriminate between active and non-active LN or predict early response to therapy. Tubulo-interstitial fibrosis was correlated to the CKD273. The LN172 score identified 92.5% of samples as LN. Few patients developed new-onset CKD. Conclusions: We validated the CKD273 and LN172 classifiers but did not identify a robust signature that could predict active LN and replace KB. The value of urinary peptidome to predict long-term CKD, or renal flares in SLE, remains to be evaluated.

Revised ISN/RPS 2018 classification of lupus renal pathology predict clinical remission

BACKGROUND

A precise description of renal histological lesions and an appropriate classification of lupus nephritis are both essential for nephrologists to guide treatment and predict prognosis among patients. The prognostic value of ISN/RPS 2003 classification is controversial. A new classification for lupus nephritis was recently proposed, namely, the revised ISN/RPS 2018 classification.

OBJECTIVE

The study aimed to evaluate the predictive value of the clinical and pathological factors according to ISN/RPS 2018 classification on renal remission among patients with proliferative lupus nephritis.

METHODS

A total number of 41 patients with proliferative lupus nephritis on adequate renal biopsy specimen between 2017 and 2018 were included. Clinical and histological variables were tested for their association with renal remission. Univariate and multivariate logistic regression analysis were performed to identify independent predictors of renal remission after 24 weeks of induction therapy.

RESULTS

After induction therapy, 56.1% of patients reached complete and partial remission and 43.9% reached no remission. In univariate analyses, baseline glomerular filtration rate (GFR), presence of anti-DNA titer, cellular crescents, interstitial inflammation, glomerulosclerosis, interstitial fibrosis, tubular atrophy and total chronicity index strongly impacted renal response. After multivariate logistic regression analysis, we identified aging, presence of cellular crescents, and high total renal chronicity index as independent predictors of renal remission. Receiver operating characteristic (ROC) analysis revealed that baseline estimated GFR (AUC = 0.708; 95% CI 0.527-0.888), anti-DNA titer (AUC = 0.674; 95% CI 0.491-0.858), cellular crescent (AUC = 0.750; 95% CI 0.585-0.915) and renal chronicity index (AUC = 0.765; 95% CI 0.585-0.915) predicted renal remission. Combining all factors achieved a perfect score predicting renal response (AUC 0.924; 95% CI 0.840-1.000).

CONCLUSION

The study identified baseline GFR, anti-DNA titer, cellular crescent, and high chronicity index according to revised ISN/RPS 2018 classification as important predictors of renal response after induction therapy in proliferative lupus nephritis.

Retrospective analysis of clinical and pathomorphological features of lupus nephritis in children

PURPOSE

The aim of the study was to evaluate the clinical course and pathomorphological correlations in Polish children with the diagnosis of lupus nephritis (LN).

METHODS

We retrospectively analyzed the medical records of 39 children hospitalized due to LN in 7 pediatric nephrology units in Poland between 2010 and 2019. Demographic data, clinical symptoms at the onset of LN and laboratory parameters were reviewed. We analyzed Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), histological LN findings with the activity (IA) and chronicity index (IC).

RESULTS

We examined 32 girls and 7 boys, median age at LN onset was 14.75 (IQR 13.0-16.0) years, SLEDAI of 22.0 (IQR 18.0-27.0) points; LN histological class: IV (59.4%), III (18.9%), III/V (10.8%), IV/V (8.1%), VI (2.7%); IA 8.0 (IQR 6.0-11.0) points, IC 1.05 (IQR 0-2.0) points. Children with nephrotic (n ​= ​22) and non-nephrotic (n ​= ​17) proteinuria differed in median Hb level (9.55, IQR 8.3-11.2 vs 10.9, IQR 10.1-11.6 ​g/L; P ​< ​0.05), albumin level (2.5, IQR 2.1-3.19 vs 3.6, IQR 3.4-4.1 ​g/dL; P ​< ​0.001), proteinuria (5.76, IQR 3.0-7.5 vs 1.08, IQR 0.53-1.50 ​g/day; P ​< ​0.0001), eGFR (53.9, IQR 27.0-68.8 vs 96.7, IQR 73.8-106.2 ​mL/min/1.73 ​m²; P ​< ​0.01) and occurrence of hypertension (77% vs 23%; P ​< ​0.01). In multivariate analysis Hb level (β ​= ​8.0; 95%CI, 1.90-14.11) was the significant predictor of eGFR<90 ​mL/min/1.73 ​m².

CONCLUSIONS

Proliferative forms of LN in children may have a varying clinical presentation. Children with LN with nephrotic range proteinuria have lower Hb level, lower eGFR and higher occurrence of hypertension. Hb level is the significant predictor of eGFR<90 ​mL/min/1.73 ​m² in children with LN.

Calcified constrictive pericarditis resulting in tamponade in a patient with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with multiorgan involvement, including heart. Pericarditis-the most common cardiac manifestation-occurs in up to 50% of cases, resulting in positive treatment outcomes. Rarely, it evolves to hazardous complications. A 50-year-old woman with SLE in clinical remission, receiving hydroxychloroquine 400 mg/day, presented to us with severe chest pain and low-grade fever. Physical examination revealed a friction rub and decreased breath sounds at the right lung base. Laboratory evaluation demonstrated leukopenia, thrombocytopenia, low C4 levels, and high acute phase reactants. Chest X-ray exhibited cardiomegaly, calcified pericardium, and right pleural effusion, confirmed by CT scan. PPD skin test and IGRA were both negative. Pericardial fluid, blood, and urine cultures for bacteria and fungi, as well as Gram and Ziehl-Neelsen stains were negative. Serological tests for viruses were also negative. The patient was diagnosed with calcified constrictive pericarditis (CP) due to SLE. She was treated with cyclophosphamide and methylprednisolone pulses, without improvement. Her clinical condition deteriorated, developing signs and symptoms compatible with cardiac tamponade (TMP), which was confirmed by Doppler echocardiography. The patient underwent pericardiectomy. A dramatic response was noted and she was discharged with prednisone 50 mg/day and azathioprine 100 mg/day. Thus, we review and discuss the relevant literature of SLE cases with CP or TMP. When an SLE patient presents with CP, infectious causes should be excluded first. To the best of our knowledge, this is the only case of SLE and calcified CP leading to TMP, hence physicians should be aware of this complication.

Stellenwert der Nierenbiopsie bei Lupusnephritis

Bei systemischem Lupus erythematodes (SLE) findet sich häufig eine renale Mitbeteiligung, der verschiedene pathogenetische Mechanismen zugrunde liegen. Die Nierenbeteiligung hat einen negativen Einfluss auf die Prognose des SLE, insbesondere bei progredienter Niereninsuffizienz. Eine Nierenbiopsie ist aufgrund der Heterogenität der Nierenbeteiligung und der damit verbundenen therapeutischen Konsequenzen unabdingbar. Sie kann durch nicht-invasive Untersuchungen wie die Urindiagnostik oder Serologie nicht ersetzt werden, da das Ausmaß der Proteinurie oder der Mikrohämaturie keine sicheren Rückschlüsse auf den Schweregrad, die Pathogenese und die Prognose der Nierenbeteiligung erlauben. Die Nierenbiopsie gibt neben der korrekten Klassifikation der Lupusnephritis (LN) Informationen über die Mitbeteiligung des Niereninterstitium, der intrarenalen Gefäße und der Aktivität sowie Chronizität der Nephritis. Auch kann der Pathologe die Frage beantworten, inwieweit mit einer Besserung der Nierenfunktion unter Therapie gerechnet werden kann. Der folgende Beitrag gibt einen Überblick über den Stellenwert der Nierenbiopsie bei SLE, der revidierten Klassifikation der LN von 2018 einschließlich Sonderformen der LN und über die Implikationen des Biopsie-Ergebnisses für die Therapie.

Uric acid and kidney damage in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that affects multiple organs; lupus nephritis (LN) is one of the most severe complications of SLE. In the kidneys, an intense inflammatory reaction affects the glomeruli and tubular interstitium. Uric acid has been considered a key molecule in the pathogenesis of some conditions such as metabolic syndrome, hypertension, and kidney disease as it is produced by injured cells and promotes immune-inflammatory responses. In this regard, high serum uric acid concentrations may be involved in the activation of some inflammatory pathways, associated with kidney damage in SLE. Therefore, the purpose of this article was to review the main physiological mechanisms and clinical data on the association between serum uric acid and kidney damage in SLE. Scientific evidence indicates that hyperuricemia has the potential to be an adjuvant in the development and progression of kidney manifestations in SLE. Uric acid may promote the activation of inflammatory pathways and the formation and deposition of autoantibodies in kidneys, leading to a reduction of glomerular filtration rate. Other potential mechanisms of this association include the presence of polymorphisms in the urate transporters, metabolic syndrome, use of some medications, and other situations associated with a reduced renal excretion of uric acid.

Anti-C1q antibodies in lupus nephritis and their correlation with the disease activity

Systemic lupus erythematosus (SLE) is an autoimmune connective tissue disorder. Renal involvement usually develops in the first few years of illness and should be detected early by periodic urine analysis and quantitation of proteinuria. The aim of our work was to evaluate the biological marker [anti-complement 1q antibodies (anti-C1q Ab)] in lupus nephritis (LN) patients and its correlation to SLE disease activity. Sixty-five subjects were divided into four groups; Group I: SLE patients with LN (proteinuria >0.5 g/day), Group II: SLE patients without LN (all of them had a lupus flares rather than nephritis; active nonrenal), Group III: SLE patients without any activity (inactive disease), and Group IV: Control group. All subjects underwent urine analysis, complete blood picture, liver function tests, kidney function tests, albumin/ creatinine ratio, antinuclear antibody, anti-double stranded DNA (anti-dsDNA) antibody, C3, C4, and anti-C1q Ab. All patients in the first group underwent renal biopsy and pathological diagnosis showed: Class II in two patients, Class III and IV in nine patients, and Class V in four patients. Anti-C1q Ab were found in the serum of SLE patients and not in the control group and showed an association with active lupus with much higher concentration in active renal group, specifically those with severe renal histological lesions (proliferative form). There was significant statistical positive correlation between anti-C1q Ab with anti-dsDNA and SLE disease activity index in both active groups. There was statistically significant negative correlation between anti-C1q Ab with C3 and C4 in both active groups. Anti-C1q Ab could be used as useful marker for active lupus, especially with nephritis.

Wire-loop lesion is associated with serological immune abnormality, but not renal prognosis, in lupus nephritis

BACKGROUND

Wire-loop lesion (WL) is one of the active lesions of lupus nephritis (LN). However, few reports have focused on the clinicopathological relationships of WL to serological immune abnormality and renal prognosis.

METHODS

We enrolled 126 Japanese LN patients subjected to renal biopsy in 11 hospitals from 2000 to 2018. In patients with class III or IV of the International Society of Nephrology/Renal Pathology Society classification, we retrospectively compared clinicopathological findings between those with WL (WL+ group) and without WL (WL- group) to detect factors associated with WL. Chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate of <60 mL/min/1.73m² for more than three months. We also compared these findings between those with CKD (CKD+ group) and without CKD (CKD- group) at the last visit to investigate factors associated with renal prognosis.

RESULTS

Of 126 patients, 100 (79.4%) were classified as class III or IV. WL was found in 36 (36.0%) of them. Although the renal function did not differ, the WL+ group had a higher titre of serum anti-dsDNA antibodies and lower serum complement 3 levels than the WL- group. Linear regression analysis revealed a significant association only between anti-dsDNA antibodies and WL (β = 0.27, 95% confidence interval (CI) 0.001-0.100, p = 0.01). Of these patients, 69 were tracked for 59.6 ± 55.1 months. Kaplan-Meier analysis showed no difference in renal prognosis between these groups. Next, the CKD+ group included 15 (22.1%) patients. They were older and had higher frequencies of hypertension and hyperuricaemia, serum creatinine (Cr) level, glomerulosclerosis, interstitial inflammation, interstitial fibrosis and tubular atrophy than the CKD- group at the time of renal biopsy. The frequency of WL was not significantly different. Cox regression analysis revealed significant associations of CKD with hypertension, hyperuricaemia, serum Cr level at the time of renal biopsy clinically and with tubular atrophy histologically.

CONCLUSIONS

WL was associated with serum anti-dsDNA antibodies but not with renal prognosis, suggesting that WL reflects immune abnormality but is not an independent factor predictive of renal prognosis in LN.

Towards Precision Medicine in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a remarkable condition characterised by diversity amongst its clinical features and immunological abnormalities. In this review, we attempt to capture the major immunological changes linked to the pathophysiology of lupus and discuss the challenge it presents in moving towards the concept of precision medicine. Currently broadly similar types of drugs, e.g., steroids, immunosuppressives, hydroxychloroquine are used to treat many of the diverse clinical features of SLE. We suspect that, as the precise immunopathological abnormalities differ between the various organs/systems in lupus patients, it will be some time before precision medicine can be fully applied to SLE.

Managing lupus nephritis: A guide for nurse practitioners

Lupus nephritis (LN) is a severe manifestation of systemic lupus erythematosus, an autoimmune disease that results in multiple organ injuries. LN is challenging to manage because it mimics the clinical presentations of other diseases. This article highlights recommendations for the management of lupus erythematosus to improve quality of life. In addition, it provides NPs with evidence-based guidelines for managing patients with LN for positive health outcomes.

A Predictive Model for Estimation Risk of Proliferative Lupus Nephritis

BACKGROUND

Lupus nephritis (LN) is classified by renal biopsy into proliferative and nonproliferative forms, with distinct prognoses, but renal biopsy is not available for every LN patient. The present study aimed to establish an alternate tool by building a predictive model to evaluate the probability of proliferative LN.

METHODS

In this retrospective cohort with biopsy-proven LN, 382 patients in development cohort, 193 in internal validation cohort, and 164 newly diagnosed patients in external validation cohort were selected. Logistic regression model was established, and the concordance statistics (C-statistics), Akaike information criterion (AIC), integrated discrimination improvement, Hosmer-Lemeshow test, and net reclassification improvement were calculated to evaluate the performance and validation of models.

RESULTS

The prevalence of proliferative LN was 77.7% in the whole cohort. A model, including age, gender, systolic blood pressure, hemoglobin, proteinuria, hematuria, and serum C3, performed well on good-of-fit and discrimination in the development chohort to predict the risk of proliferative LN (291 for AIC and 0.84 for C-statistics). In the internal and external validation cohorts, this model showed good capability for discrimination and calibration (0.84 and 0.82 for C-statistics, and 0.99 and 0.75 for P values, respectively).

CONCLUSION

This study developed and validated a model including demographic and clinical indices to evaluate the probability of presenting proliferative LN to guide therapeutic decisions and outcomes.

CCR6+ Th cell distribution differentiates systemic lupus erythematosus patients based on anti-dsDNA antibody status

Background

Systemic lupus erythematosus (SLE) disease has been shown to be associated with the generation of multiple auto-antibodies. Among these, anti-dsDNA antibodies (anti-DNAs) are specific and play a pathogenic role in SLE. Indeed, anti-DNA⁺ SLE patients display a worse disease course. The generation of these pathogenic anti-DNAs has been attributed to the interaction between aberrant T helper (Th) cells and autoimmune B cells. Thus, in this study we have investigated whether CCR6⁺Th cells have the ability to differentiate SLE patients based on anti-DNA status, and if their distribution has any correlation with disease activity.

Methods

We recruited 25 anti-DNA⁺ and 25 anti-DNA⁻ treatment-naive onset SLE patients, matched for various clinical characteristics in our nested matched case-control study. CCR6⁺ Th cells and their additional subsets were analyzed in each patient by flow cytometry.

Results

Anti-DNA⁺ SLE patients specifically had a higher percentage of Th cells expressing CCR6 and CXCR3. Further analysis of CCR6⁺ Th cell subsets showed that anti-DNA⁺ SLE patients had elevated proportions of Th9, Th17, Th17.1 and CCR4/CXCR3 double-negative (DN) cells. However, the proportions of CCR6⁻ Th subsets, including Th1 and Th2 cells, did not show any association with anti-DNA status. Finally, we identified a correlation between CCR6⁺ Th subsets and clinical indicators, specifically in anti-DNA⁺ SLE patients.

Conclusions

Our data indicated that CCR6⁺ Th cells and their subsets were elevated and correlated with disease activity in anti-DNA⁺ SLE patients. We speculated that CCR6⁺ Th cells may contribute to distinct disease severity in anti-DNA⁺ SLE patients.

Integrative therapy decreases the risk of lupus nephritis in patients with systemic lupus erythematosus: A population-based retrospective cohort study

ETHNOPHARMACOLOGICAL RELEVANCE

Evidence on alleviating the risk of lupus nephritis by integrative therapy with conventional medicine (CM) and herbal medicine (HM) had not been addressed.

AIM OF THE STUDY

We investigated the integrative effect associated the risk by a retrospective Systemic Lupus Erythematosus (SLE) cohort from Taiwan National Health Insurance Research Database (NHIRD).

MATERIALS AND METHODS

SLE patients with a catastrophic illness certificate (CIC) were retrospectively enrolled from the SLE cohort of the Taiwan NHIRD between 1997 and 2011. The patients were divided into an integrative medicine (IM: integrated CM plus HM) and a non-IM (CM only) group with 1:1 propensity score matching. Cox proportional regression model and the Kaplan-Meier method were conducted to estimate the hazard ratio (HR) for lupus nephritis in the cohort.

RESULTS

Among 16,645 newly diagnosed SLE patients holding a CIC (SLE/CIC), 1933 had received HM and 1571 had received no HM treatment. After propensity score matching, there were 273 patients with lupus nephritis-120 in the IM group and 153 in the non-IM group. The adjusted HR (0.68, 95% confidence interval [CI]: 0.54-0.87, p<0.01) for lupus nephritis was lower in the IM group than in the non-IM group. The adjusted HR (0.69, 95% CI: 0.54-0.88, p<0.001) for lupus nephritis was also lower in the group of patients who had received CM plus HM than in the group that received CM only. The core pattern of HM prescriptions, which were integrated with CM for preventing lupus nephritis, was "Sheng-Di-Huang" (raw Rehmannia glutinosa Libosch.), "Mu-Dan-Pi" (Paeonia suffruticosa Andr.), "Dan-Shan" (Salvia miltiorrhiza Bge.), "Zhi-Bo-Di-Huang-Wan.", and "Chi-Shao" (Paeoniae lactiflorae Rubra).

CONCLUSION

Integrative therapy decreased the risk of lupus nephritis among SLE patients in Taiwan. Further investigation of the pharmacological mechanism and clinical efficacy are warranted.

Urinary sediment suggests lupus nephritis histology

Objectives

The objective of this paper was to evaluate correlations between kidney biopsy indexes (activity and chronicity) and urinary sediment findings; the secondary objective was to find which components of urinary sediment can discriminate proliferative from other classes of lupus nephritis.

Methods

Lupus nephritis patients scheduled for a kidney biopsy were included in our study. The morning before the kidney biopsy, we took urine samples from each patient. Receiver operating characteristic (ROC) curves were plotted to determine the area under the curve (AUC) of each test for detecting proliferative lupus nephritis; a classification tree was calculated to select a set of values that best-predicted lupus nephritis classes.

Results

We included 51 patients, 36 of whom were women (70.6%). Correlations of lupus nephritis activity index with the counts in the urinary sediment of erythrocytes (isomorphic and dysmorphic), acanthocytes, and leukocytes were 0.65 ( p < 0.0001) 0.62 ( p < 0.0001) and 0.22 ( p = 0.1228), respectively. Correlations of lupus nephritis chronicity index with the counts of erythrocytes, acanthocytes, and leukocytes were 0.60 ( p ≤ 0.0001), 0.52 ( p = 0.0001) and 0.17 ( p = 0.2300), respectively. Our classification tree had an accuracy of 84.3%.

Conclusions

Evaluation of urine sediment reflects lupus nephritis histology.