From systemic lupus erythematosus to lupus nephritis: The evolving road to targeted therapies.

Systemic lupus erythematosus is a chronic autoimmune disease characterized by loss of tolerance against nuclear and cytoplasmic self-antigens, induction of immunity and tissue inflammation. Lupus nephritis (LN), the most important predictor of morbidity in SLE, develops in almost 30% of SLE patients at disease onset and in up to 50-60% within the first 10 years. Firstly, in this review, we put the pathogenic mechanisms of the disease into a conceptual frame, giving emphasis to the role of the innate immune system in this loss of self-tolerance and the induction of the adaptive immune response. In this aspect, many mechanisms have been described such as dysregulation and acceleration of cell-death pathways, an aberrant clearance and overload of immunogenic acid-nucleic-containing debris and IC, and the involvement of antigen-presenting cells and other innate immune cells in the induction of this adaptive immune response. This result in a clonal expansion of autoreactive lymphocytes with generation of effector T-cells, memory B-cells and plasma cells that produce autoantibodies that will cause kidney damage. Secondly, we review the immunological pathways of damage in the kidney parenchyma, initiated by autoantibody binding and immune complex deposition, and followed by complement-mediated microvascular injury, activation of kidney stromal cells and the recruitment of leukocytes. Finally, we summarize the rationale for the treatment of LN, from conventional to new targeted therapies, focusing on their systemic immunologic effects and the minimization of podocytary damage.

Long-term outcomes of COVID-19 vaccination in patients with rare and complex connective tissue diseases: The ERN-ReCONNET VACCINATE study.

Background: Vaccination is one of the most important measures to contain the COVID-19 pandemic, especially for frail patients. VACCINATE is a multicentre prospective observational study promoted by the European Reference Network on Rare and Complex Connective Tissue and Musculoskeletal Diseases (ERN ReCONNET) aimed at assessing the long-term outcomes of COVID-19 vaccination in patients with rare and complex connective tissue diseases (rcCTDs) in terms of efficacy and safety. Methods: Adult rcCTDs patients were eligible for recruitment. Demographic, clinical and vaccination data were collected at enrolment. Follow-up visits were scheduled 4, 12, 24, 36 and 48 weeks after completion of the first vaccination cycle; data on adverse events, disease exacerbations and the occurrence of new SARS-CoV-2 infections were collected at these time-points. Findings: 365 rcCTDs patients (87 % female, mean age 51.8 ± 14.6 years) were recruited. Overall, 200 patients (54.8 %) experienced at least one adverse event, generally mild and in most cases occurring early after the vaccination. During follow-up, 55 disease exacerbations were recorded in 39 patients (10.7 %), distributed over the entire observation period, although most frequently within 4 weeks after completion of the vaccination cycle. The incidence of new SARS-CoV-2 infections was 8.9 per 1000 person-months, with no cases within 12 weeks from vaccine administration and an increasing trend of infections moving away from the primary vaccination cycle. Only one case of severe COVID-19 was reported during the study period. Interpretation: COVID-19 vaccination seems effective and safe in rcCTDs patients. The rate of new infections was rather low and serious infections were uncommon in our cohort. No increased risk of disease flares was observed compared to previous disease history; however, such exacerbations may be potentially severe, emphasising the need for close monitoring of our patients.

Worse long-term renal outcome of lupus nephritis patients of African descent living in Europe.

INTRODUCTION: Prognosis of lupus nephritis (LN) among patients of African descent living in Europe has been understudied. METHODS: In a retrospective study performed in two European university hospitals, we compared the prognosis of LN in patients of African descent or Caucasians. Remission was defined as a urine protein to creatinine (uP/C) ratio<0.5 g/g and a serum creatinine value<120% of baseline. Renal relapse was defined as the reappearance of a uP/C>1 g/g, leading to a repeat kidney biopsy and/or immunosuppressive treatment change. Chronic kidney disease (CKD) was defined as estimated glomerular filtration rate≤60 mL/min/1.73 m2. Adherence was retrospectively assessed through medical files and/or hydroxychloroquine level measurements. RESULTS: 52 patients of African descent and 85 Caucasian patients were included in this analysis. Class III and isolated class V LN were more common among patients of African descent. Time to first renal remission did not differ between ethnic subgroups. By contrast, patients of African descent suffered from earlier renal flares, CKD was more common and time to CKD was shorter after a flare. In a multivariate analysis, African ancestry was an independent risk factor for progression to CKD. We observed no significant difference in non-adherence to treatment between the two groups. CONCLUSION: LN patients of African descent have worse renal outcomes, mainly explained by a higher rate of renal flare.

Treat-to-Target in Lupus Nephritis. What is the Role of the Repeat Kidney Biopsy?

Kidney involvement, termed lupus nephritis (LN), develops in 35-60% of patients with systemic lupus erythematosus, often early during the disease course. When not treated promptly and efficiently, LN may lead to rapid and severe loss of kidney function, being the reason why it is considered one of the most severe lupus manifestations. Despite improved pharmacotherapy, 5-20% of LN patients develop end-stage kidney disease within ten years from the LN diagnosis. While the principal ground of LN therapy is prevention of renal function worsening, resembling a race against nephron loss, consensual agreement upon outcome measures and clinically meaningful short- and long-term targets of LN therapy have yet to be determined. Literature points to the importance of inclusion of tissue-based approaches in the determination of those targets, and evidence accumulates regarding the importance of per-protocol repeat kidney biopsies in the evaluation of the initial phase of therapy and prediction of long-term renal prognosis. The latter leads to the hypothesis that the information gleaned from repeat biopsies may contribute to optimised therapeutic decision making, and, therefore, increased probability to attain complete renal response in the short term, and a more favourable renal prognosis within a longer prospect. The multinational project ReBioLup was recently designed to serve as a key contributor to form evidence about the role of per-protocol repeat biopsies in a randomised fashion and aspires to unify the global LN community towards improved kidney and patient survival.

Real-life prevalence of progressive fibrosing interstitial lung diseases.

The concept of progressive fibrosing interstitial lung disease (PF-ILD) has recently emerged. However, real-life proportion of PF-ILDs outside IPF is still hard to evaluate. Therefore, we sought to estimate the proportion of PF-ILD in our ILD cohort. We also determined the proportion of ILD subtypes within PF-ILD and investigated factors associated with PF-ILDs. Finally, we quantified interobserver agreement between radiologists for the assessment of fibrosis. We reviewed the files of ILD patients discussed in multidisciplinary discussion between January 1st 2017 and December 31st 2019. Clinical data, pulmonary function tests (PFTs) and high-resolution computed tomography (HRCTs) were centrally reviewed. Fibrosis was defined as the presence of traction bronchiectasis, reticulations with/out honeycombing. Progression was defined as a relative forced vital capacity (FVC) decline of ≥ 10% in ≤ 24 months or 5% < FVC decline < 10% and progression of fibrosis on HRCT in ≤ 24 months. 464 consecutive ILD patients were included. 105 had a diagnosis of IPF (23%). Most frequent non-IPF ILD were connective tissue disease (CTD)-associated ILD (22%), hypersensitivity pneumonitis (13%), unclassifiable ILD (10%) and sarcoidosis (8%). Features of fibrosis were common (82% of CTD-ILD, 81% of HP, 95% of uILD). After review of HRCTs and PFTs, 68 patients (19% of non-IPF ILD) had a PF-ILD according to our criteria. Interobserver agreement for fibrosis between radiologists was excellent (Cohen's kappa 0.86). The main diagnosis among PF-ILD were CTD-ILD (36%), HP (22%) and uILD (20%). PF-ILD patients were significantly older than non-F-ILD (P = 0.0005). PF-ILDs represent about 20% of ILDs outside IPF. This provides an estimation of the proportion of patients who might benefit from antifibrotics. Interobserver agreement between radiologists for the diagnosis of fibrotic ILD is excellent.

High p16INK4a, a marker of cellular senescence, is associated with renal injury, impairment and outcome in lupus nephritis.

OBJECTIVES: Because a significant fraction of patients with lupus nephritis (LN) develops renal impairment, there is a need to better understand the mechanisms underlying disease progression. Here, we assessed for cellular senescence in the LN kidney, and its association with disease severity and outcome. METHODS: We enumerated the number of cells positive for p16INK4a protein, a marker of cellular senescence, by immunohistochemistry followed by digital quantification, on renal biopsies from 40 patients with active LN. We tested for an association of p16INK4a with renal fibrosis, CD8+ T cell infiltration, systemic disease and renal function at baseline and at 5 years. RESULTS: The presence of p16INK4a-positive cells was significantly associated with lower estimated glomerular filtration rate at baseline and 5 years post-treatment, independently of patient demographics and systemic disease parameters. It was also associated with higher baseline renal fibrosis and CD8+ T cell infiltration. Interestingly, we observed marked spatial co-distribution of glomerular p16INK4a-positive cells with CD8+ T cells. CONCLUSION: We demonstrate, for the first time, that LN biopsies characterised by renal impairment display increased p16INK4a-positive cells, associated with higher fibrosis and CD8+ T cell infiltration. Cellular senescence may represent a kidney-intrinsic disease mechanism and potentially, a novel therapeutic target in LN.

Absence of renal remission portends poor long-term kidney outcome in lupus nephritis.

BACKGROUND: The very long-term consequences of absence of remission in lupus nephritis (LN) remain understudied. METHODS: In this retrospective analysis, we studied a selected cohort of 128 patients with biopsy-proven class III, IV or V incident LN followed for a median period of 134 months (minimum 25). Remission was defined as a urine protein to creatinine (uP:C) ratio <0.5 g/g and a serum creatinine value <120% of baseline. Renal relapse was defined as the reappearance of a uP:C >1 g/g, leading to a repeat kidney biopsy and treatment change. Poor long-term renal outcome was defined as the presence of chronic kidney disease (CKD). RESULTS: Twenty per cent of patients never achieved renal remission. Their baseline characteristics did not differ from those who did. Absence of renal remission was associated with a threefold higher risk of CKD (48% vs 16%) and a 10-fold higher risk of end-stage renal disease (20% vs 2%). Patients achieving early remission had significantly higher estimated glomerular filtration rate (eGFR) at last follow-up compared with late remitters. Accordingly, patients with CKD at last follow-up had statistically longer time to remission. Among patients who achieved remission, 32% relapsed, with a negative impact on renal outcome, that is, lower eGFR values and higher proportion of CKD (33% vs 8%). CONCLUSION: Early remission should be achieved to better preserve long-term renal function.

Molecular Signatures of Kidney Antibody-Secreting Cells in Lupus Patients With Active Nephritis Upon Immunosuppressive Therapy.

OBJECTIVE: This study was undertaken to characterize kidney and urine antibody-secreting cells (ASCs) from patients with active lupus nephritis, before and after induction therapy. METHODS: We included patients with biopsy-proven active lupus nephritis and performed anti-CD138 staining of kidney biopsy samples to visualize ASCs. We performed single-cell gene expression profiling on sorted ASCs from fresh biopsy samples using multiplex reverse transcriptase-polymerase chain reaction. We used a gene set that allowed for the study of ASC maturation from plasmablasts to long-lived plasma cells. We quantified urine ASCs from untreated patients with lupus nephritis at diagnosis and after 6 months of prospective follow-up during induction therapy. RESULTS: The number of kidney CD138+ ASCs in 46 untreated patients with lupus nephritis was correlated with a low estimated glomerular filtration rate and with tubulointerstitial damage. Most kidney ASCs from 3 untreated patients had a plasmablast molecular signature; in contrast, in 4 patients with refractory lupus nephritis, the kidney ASCs were mainly long-lived plasma cells, representing an ASC transcriptional profile similar to that in the bone marrow of 2 healthy donors. Some urine ASCs with a plasmablast signature were detected in patients with untreated active lupus nephritis. The presence of urine ASCs at 6 months was associated with treatment failure. CONCLUSION: Our results suggest potential for ASC-directed therapy in refractory lupus nephritis.

Management of Lupus Nephritis.

Lupus nephritis (LN) is a frequent and severe manifestation of systemic lupus erythematosus. The main goal of the management of LN is to avoid chronic kidney disease (CKD). Current treatment strategies remain unsatisfactory in terms of complete renal response, prevention of relapses, CKD, and progression to end-stage kidney disease. To improve the prognosis of LN, recent data suggest that we should (i) modify our treat-to-target approach by including, in addition to a clinical target, a pathological target and (ii) switch from conventional sequential therapy to combination therapy. Here, we also review the results of recent controlled randomized trials.

The impact of COVID-19 on rare and complex connective tissue diseases: the experience of ERN ReCONNET.

During the COVID-19 pandemic, the need to provide high-level care for a large number of patients with COVID-19 has affected resourcing for, and limited the routine care of, all other conditions. The impact of this health emergency is particularly relevant in the rare connective tissue diseases (rCTDs) communities, as discussed in this Perspective article by the multi-stakeholder European Reference Network on Rare and Complex Connective Tissue and Musculoskeletal Diseases (ERN ReCONNET). The clinical, organizational and health economic challenges faced by health-care providers, institutions, patients and their families during the SARS-CoV-2 outbreak have demonstrated the importance of ensuring continuity of care in the management of rCTDs, including adequate diagnostics and monitoring protocols, and highlighted the need for a structured emergency strategy. The vulnerability of patients with rCTDs needs to be taken into account when planning future health policies, in preparation for not only the post-COVID era, but also any possible new health emergencies.

Per-protocol repeat kidney biopsy portends relapse and long-term outcome in incident cases of proliferative lupus nephritis.

OBJECTIVES: In patients with LN, clinical and histological responses to treatment have been shown to be discordant. We investigated whether per-protocol repeat kidney biopsies are predictive of LN relapses and long-term renal function impairment. METHODS: Forty-two patients with incident biopsy-proven active proliferative (class III/IV±V) LN from the database of the UCLouvain were included in this retrospective study. Per-protocol repeat biopsies were performed after a median [interquartile range (IQR)] time of 24.3 (21.3-26.2) months. The National Institutes of Health activity index (AI) and chronicity index (CI) scores were assessed in all biopsies. RESULTS: Despite a moderate correlation between urinary protein/creatinine ratios (UPCR) and AI scores at repeat biopsy (r = 0.48; P = 0.001), 10 patients (23.8%) with UPCR < 1.0 g/g still had a high degree of histological activity (AI > 3). High AI scores (continuous) in repeat biopsies were associated with an increased probability and/or shorter time to renal relapse (n = 11) following the repeat biopsy [hazard ratio (HR) = 1.2, 95% CI: 1.1, 1.3; P = 0.007], independently of proteinuria levels. High CI scores (continuous) in repeat biopsies were associated with a sustained increase in serum creatinine levels corresponding to ≥120% of the baseline value (HR = 1.8, 95% CI: 1.1, 2.9; P = 0.016) through a median (IQR) follow-up time of 131.5 (73.8-178.2) months, being also the case for acute tubulointerstitial inflammation and interstitial fibrosis/tubular atrophy in repeat but not baseline biopsies. CONCLUSION: Our results highlight the usefulness of per-protocol repeat biopsies, herein performed after a median time of 24 months from baseline, as an integral part of the treatment evaluation, also in patients showing adequate clinical response.

Prediction of prognosis and renal outcome in lupus nephritis.

Lupus nephritis (LN) is a severe manifestation of SLE, characterised by subendothelial and/or subepithelial immune complex depositions in the afflicted kidney, resulting in extensive injury and nephron loss during the acute phase and eventually chronic irreversible damage and renal function impairment if not treated effectively. The therapeutic management of LN has improved during the last decades, but the imperative need for consensual outcome measures remains. In order to design trials with success potentiality, it is important to define clinically important short-term and long-term targets of therapeutic and non-therapeutic intervention. While it is known that early response to treatment is coupled with favourable renal outcomes, early predictors of renal function impairment are lacking. The information gleaned from kidney biopsies may provide important insights in this direction. Alas, baseline clinical and histopathological information has not been shown to be informative. By contrast, accumulating evidence of pronounced discrepancies between clinical and histopathological outcomes after the initial phase of immunosuppression has prompted investigations of the potential usefulness of per-protocol repeat kidney biopsies as an integral part of treatment evaluation, including patients showing adequate clinical response. This approach appears to have merit. Hopefully, clinical, molecular or genetic markers that reliably reflect kidney histopathology and portend the long-term prognosis will be identified. Novel non-invasive imaging methods and employment of the evolving artificial intelligence in pattern recognition may also be helpful towards these goals. The molecular and cellular characterisation of SLE and LN will hopefully result in novel therapeutic modalities, maybe new taxonomy perspectives, and ultimately personalised management.

Multidisciplinary management of interstitial lung diseases: A real-life study.

BACKGROUND: The guidelines on idiopathic pulmonary fibrosis (IPF) diagnosis established the crucial role of multidisciplinary discussion (MDD) in the diagnosis of interstitial lung diseases (ILD). However, real-life evaluation of MDD remains scarce. Our aim was to study the impact of a well-structured MDD on etiological assessment, diagnosis, and management of ILD. METHODS: We collected and analysed all relevant data on patients concerning diagnosis and treatment before and after MDD during the year 2017. RESULTS: One hundred fifty patients were included in the analysis. MDD had a significant impact on management: 42% of diagnoses were revised and the number of unclassifiable ILD was significantly reduced. Lung biopsy was performed in 26 patients (12 cryobiopsies and 14 surgical biopsies). The most prevalent diagnoses were connective-tissue disease associated ILD (32%), idiopathic pulmonary fibrosis (23%), hypersensitivity pneumonitis (13%) and granulomatous ILD (7%). MDD led to a change or initiation of treatment in 55% of cases. Nine patients were evaluated for transplantation, 23 patients were screened for academic or sponsored clinical trials and an 8-fold increase in rehabilitation inclusion was observed. CONCLUSION: Our results confirm the benefits of MDD on ILD management and diagnosis. MDD also facilitates access to non-pharmacological therapies and clinical trials.

Systemic lupus erythematosus: state of the art on clinical practice guidelines.

Systemic lupus erythematosus (SLE) is the paradigm of systemic autoimmune diseases characterised by a wide spectrum of clinical manifestations with an unpredictable relapsing-remitting course. The aim of the present work was to identify current available clinical practice guidelines (CPGs) for SLE, to provide their review and to identify physicians' and patients' unmet needs. Twenty-three original guidelines published between 2004 and 2017 were identified. Many aspects of disease management are covered, including global disease management, lupus nephritis and neuropsychiatric involvement, management of pregnancies, vaccinations and comorbidities monitoring. Unmet needs relate with disease management of some clinical manifestations and adherence to treatment. Many patient's unmet needs have been identified starting with faster diagnosis, need for more therapeutic options, guidelines on lifestyle issues, attention to quality of life and adequate education.

Idiopathic inflammatory myopathies: state of the art on clinical practice guidelines [corrected].

Idiopathic inflammatory myopathies (IIMs) encompass a heterogeneous group of rare autoimmune diseases characterised by muscle weakness and inflammation, but in antisynthetase syndrome arthritis and interstitial lung disease are more frequent and often inaugurate the disease. Clinical practice guidelines (CPGs) have been proposed for IIMs, but they are sparse and heterogeneous. This work aimed at identifying: i) current available CPGs for IIMs, ii) patients ' and clinicians' unmet needs not covered by CPGs. It has been performed in the framework of the European Reference Network on rare and complex connective tissue and musculoskeletal diseases (ReCONNET), a network of centre of expertise and patients funded by the European Union's Health Programme. Fourteen original CPGs were identified, notably recommending that: i) extra-muscular involvements should be assessed; ii) corticosteroids and methotrexate or azathioprine are first-line therapies of IIMs. ii) IVIG is a treatment of resistant-DM that may be also used in other resistant-IIMs; iii) physical therapy and sun protection (in DM patients) are part of the treatment; v) tumour screening for patients with DM include imaging of chest, abdomen, pelvis and breast (in woman) along with colonoscopy (in patients over 50 years); vi) disease activity and damages should be monitor using standardised and validated tools. Yet, only half of these CPGs were evidence-based. Crucial unmet needs were identified both by patients and clinicians. In particular, there was a lack of large multidisciplinary working group and of patients ' preferences. The following fields were not or inappropriately targeted: diagnosis; management of extra-muscular involvements other than skin; co-morbidities and severe manifestations.

Brief Report: The Euro-Lupus Low-Dose Intravenous Cyclophosphamide Regimen Does Not Impact the Ovarian Reserve, as Measured by Serum Levels of Anti-Müllerian Hormone.

OBJECTIVE: The Euro-Lupus regimen of low-dose intravenous cyclophosphamide (IV CYC) (cumulative dose of 3 gm) was developed to reduce gonadal toxicity. To address the possibility of a marginal effect on the ovarian reserve, we measured serum titers of anti-Müllerian hormone (AMH) in patients with systemic lupus erythematosus (SLE) treated with the Euro-Lupus regimen and compared them with those measured in patients who were treated with higher doses of IV CYC or were never treated with IV CYC. METHODS: Serum AMH levels were measured by enzyme-linked immunosorbent assay in a cohort of 155 premenopausal SLE patients; 30 of these patients had been treated with the Euro-Lupus regimen, and 24 had received higher doses of IV CYC. None had received oral CYC. AMH levels were age-adjusted using a slope computed from levels measured across the group of SLE patients who had not been treated with IV CYC. Demographic and clinical data were collected. RESULTS: Serum titers of AMH measured in SLE patients treated with the Euro-Lupus IV CYC regimen (median dose 1.46 ng/ml) did not differ from those measured in patients never treated with the cytotoxic drug (median 1.85 ng/ml). As expected, patients given >6 gm of IV CYC had significantly lower serum titers of AMH (median 0.83 ng/ml) compared with those never treated with IV CYC (P = 0.047). Median serum AMH titers did not change before (1.24 ng/ml) and after (2.50 ng/ml) treatment with the Euro-Lupus IV CYC regimen in the subset of patients for whom paired samples could be tested (P = 0.43). CONCLUSION: The Euro-Lupus regimen of low-dose IV CYC does not impact the ovarian reserve of SLE patients and can therefore be proposed as treatment in patients seeking to become pregnant.

Long-term follow-up of the MAINTAIN Nephritis Trial, comparing azathioprine and mycophenolate mofetil as maintenance therapy of lupus nephritis.

OBJECTIVE: To report the 10-year follow-up of the MAINTAIN Nephritis Trial comparing azathioprine (AZA) and mycophenolate mofetil (MMF) as maintenance therapy of proliferative lupus nephritis, and to test different definitions of early response as predictors of long-term renal outcome. METHODS: In 2014, data on survival, kidney function, 24 h proteinuria, renal flares and other outcomes were collected for the 105 patients randomised between 2002 and 2006, except in 13 lost to follow-up. RESULTS: Death (2 and 3 in the AZA and MMF groups, respectively) and end-stage renal disease (1 and 3, respectively) were rare events. Time to renal flare (22 and 19 flares in AZA and MMF groups, respectively) did not differ between AZA and MMF patients. Patients with good long-term renal outcome had a much more stringent early decrease of 24 h proteinuria compared with patients with poor outcome. The positive predictive value of a 24 h proteinuria <0.5 g/day at 3 months, 6 months and 12 months for a good long-term renal outcome was excellent (between 89% and 92%). Inclusion of renal function and urinalysis in the early response criteria did not impact the value of early proteinuria decrease as long-term prognostic marker. CONCLUSIONS: The long-term follow-up data of the MAINTAIN Nephritis Trial do not indicate that MMF is superior to AZA as maintenance therapy in a Caucasian population suffering from proliferative lupus nephritis. Moreover, we confirm the excellent positive predictive value of an early proteinuria decrease for long-term renal outcome. TRIAL REGISTRATION NUMBER: NCT00204022.