New insights into the pathogenesis and management of lupus in children

Potential regulatory role of the Nrf2/HMGB1/TLR4/NF-κB signaling pathway in lupus nephritis

OBJECTIVES

Systemic lupus erythematosus is an autoimmune disease that involves multiple organ systems. One of its major complications, lupus nephritis (LN), is associated with a high mortality rate, and children-onset LN have a more severe course and worse prognosis than adults. Oxidative stress and inflammatory responses are involved in LN development and pathogenesis. Thus, this study aimed to explore the role of signaling regulation of the Nrf2/HMGB1/TLR/NF-κB pathway in LN pathogenesis and unravel the expression of TLR4+CXCR4+ plasma cells subset (PCs) in LN.

METHODS

C57BL/6 and MRL/lpr mice were divided into four groups: control, model, vector control, and Nrf2 overexpression groups. The vector control and Nrf2 overexpression groups were injected with adenoviral vectors into the kidney in situ. Pathological changes in kidney tissues were observed by hematoxylin-eosin staining. The expression of Nrf2, HMGB1, TLR4, NF-κB, and downstream inflammatory factors in kidney samples was analyzed by quantitative polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay. The ratios of TLR4+CXCR4+ PC subsets in the blood and kidneys of mice were determined by flow cytometry.

RESULTS

In MRL/lpr mice, Nrf2 was downregulated while HMGB1/TLR4/NF-κB pathway proteins were upregulated. Nrf2 overexpression decreased the expression of HMGB1, TLR4, NF-κB, and its downstream inflammatory cytokines (IL-1β and TNFα). These cytokines were negatively correlated with an increase in Nrf2 content. PC and TLR4 + CXCR4 + PCs in the blood and kidney samples were significantly increased in MRL/lpr mice; however, they were decreased upon Nrf2 overexpression.

CONCLUSION

This study showed severe kidney injury in an LN mouse model and an increased ratio of TLR4 + CXCR4 + PCs. Furthermore, we observed that Nrf2 regulates LN immune response through the Nrf2/HMGB1/TLR4/NF-κB pathway, which can be considered an important target for LN treatment. The clinical value of the findings of our study requires further investigation.

The Disease with a Thousand Faces and the Human Microbiome-A Physiopathogenic Intercorrelation in Pediatric Practice

Numerous interrelationships are known in the literature that have the final effect of unmasking or influencing various pathologies. Among these, the present article aims to discuss the connection between systemic lupus erythematosus (SLE) and the human microbiome. The main purpose of this work is to popularize information about the impact of dysbiosis on the pathogenesis and evolutionary course of pediatric patients with SLE. Added to this is the interest in knowledge and awareness of adjunctive therapeutic means that has the ultimate goal of increasing the quality of life. The means by which this can be achieved can be briefly divided into prophylactic or curative, depending on the phase of the condition in which the patient is. We thus reiterate the importance of the clinician acquiring an overview of SLE and the human microbiome, doubled by in-depth knowledge of the physio-pathogenic interactions between the two (in part achieved through the much-studied gut-target organ axes-brain, heart, lung, skin), with the target objective being that of obtaining individualized, multimodal and efficient management for each individual patient.

Is mean platelet volume related to disease activity in systemic lupus erythematosus?

INTRODUCTION

Systemic lupus erythematosus (SLE) is a connective tissue disease that is chronic, recurrent and multisystem with unknown aetiology. There is still no single biomarker that is pathognomonic for the disease. We know that platelets are the main part of haemostasis and thrombosis. We aimed to investigate whether there is a connection between MPV with SLE and inflammatory markers.

MATERIAL AND METHODS

We have included 39 female patients with SLE and 45 controls in this study. In both groups, erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP) levels and MPV levels were investigated. Clinical findings and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) were evaluated in patients.

RESULTS

There was no significant difference between the two groups in terms of demographic data. The MPV was 8.1 ± 0.5 (mean ± SD) in the patient's group and 7.6 ± 0.3 in the control group. There was a significant difference between the two groups in terms of MPV (P < .001). The ESR level was 30.7 ± 29 in the patient's group and 16.7 ± 10 in the control group. In the patient's group, the CRP levels were higher compared with that of the control group (8.2 ± 13, 4.5 ± 4, respectively). We found a statistically significant positive correlation between MPV with arthritis (r = .310,P = .004), nephritis (r = .446,P < .001), central nervous system involvement (r = .241,P = .027), vasculitis (r = .228,P = .037) and SLEDAI (r = .329,P = .002). In our study, we found increased levels of MPV in patients with SLE. Also, we observed a positive correlation among MPV with sedimentation, CRP, clinical manifestations and SLEDAI.

CONCLUSION

We consider that MPV may be a new activation indicator for the SLE.

Tocilizumab for massive refractory pleural effusion in an adolescent with systemic lupus erythematosus

BACKGROUND

Pleural effusion in systemic lupus erythematous (SLE) is a common symptom, and recent studies demonstrated that IL-6 has a pivotal role in its pathogenesis.

CASE PRESENTATION

We report a case of a 15 years old Caucasian boy with a history of persistent pleural effusion without lung involvement or fever. Microbiological and neoplastic aetiologies were previously excluded. Based on the presence of pleuritis, malar rash, reduction of C3 and C4 levels and positivity of antinuclear antibody (ANA) and anti-double stranded DNA (dsDNA), the diagnosis of juvenile SLE (JSLE) was performed. Treatment with high dose of intravenous glucocorticoids and mycophenolate mofetil was started with partial improvement of pleural effusion. Based on this and on adults SLE cases with serositis previously reported, therapy with intravenous tocilizumab (800 mg every two weeks) was started with prompt recovery of pleural effusion.

CONCLUSION

To the best of our knowledge, this is the first case of JSLE pleuritis successfully treated with tocilizumab.

Juvenile-onset systemic lupus erythematosus: Update on clinical presentation, pathophysiology and treatment options

Juvenile-onset systemic lupus erythematosus (jSLE) accounts for up to 20% of all SLE patients. Key differences between juvenile- and adult-onset (aSLE) disease include higher disease activity, earlier development of damage, and increased use of immunosuppressive treatment in jSLE suggesting (at least partial) infectivity secondary to variable pathomechanisms. While the exact pathophysiology of jSLE remains unclear, genetic factors, immune complex deposition, complement activation, hormonal factors and immune cell dysregulation are involved to variable extents, promising future patient stratification based on immune phenotypes. Though less effective and potentially toxic, jSLE patients are treated based upon evidence from studies in aSLE cohorts. Here, age-specific clinical features of jSLE, underlying pathomechanisms, treatment options and disease outcomes will be addressed. Future directions to improve the care of jSLE patients, including implementation of the Single Hub and Access point for pediatric Rheumatology in Europe (SHARE) recommendations, biomarkers, treat to target and personalized medicine approaches are discussed.

The emerging role of immunothrombosis in paediatric conditions

BACKGROUND

Immunothrombosis is a physiological process based on the release of neutrophil extracellular traps (NETs) to immobilise, contain and kill bacteria. This is an innate immune response in which the local activation of blood coagulation exerts the critical protective function during microbial infection. In recent years, there has been much interest in the adult literature about the key role of immunothrombosis in pathologic states including thrombosis, cancer, sepsis and trauma. Currently, little research has been done into its role in paediatric conditions.

METHODS

We conducted a literature search of the National Library of Medicine (MEDLINE/PubMed) from the years 2000 to May 2018 and qualitatively identified 24 relevant papers. References of articles included for full-text review were checked for relevant publications.

RESULTS

Our aim is to summarise the most relevant evidences regarding an excessive production or defective removal of NETs in paediatric conditions. In particular, we have divided the role of immunothrombosis into acute (sepsis, necrotising enterocolitis, otitis media, neonatal arterial ischaemic stroke, haemolytic anaemic diseases) and chronic (systemic lupus erythematous, type 1 diabetes mellitus, respiratory diseases, graft-versus-host disease) conditions to find important similarities in their pathophysiology.

CONCLUSION

The field of immunothrombosis in paediatric conditions is still in its infancy. We have presented multiple pathways of NET-induced disease together with possible areas of future research and treatments.

The effectiveness and safety of biological therapeutics in juvenile-onset systemic lupus erythematosus (JSLE): a systematic review

OBJECTIVE

To systematically review and summarize the available literature regarding the effectiveness and safety of biologics in the treatment of juvenile-onset systemic lupus erythematosus.

METHODS

PubMed was systematically searched for relevant literature (2012-2017 inclusive) using the following criteria: (1) patients diagnosed with juvenile-onset systemic lupus erythematosus (≤18 years at diagnosis); (2) treatment with any biological agent; and (3) outcome measures assessing effectiveness and safety. Systematic literature reviews, meta-analyses, randomized controlled trials, cohort studies, case control studies, cross sectional surveys and case-series with ≥3 patients were included. Independent extraction of articles by two authors using predefined criteria was performed. The quality of each study was assessed using CASP tools and Oxford CEBM Levels of Evidence.

RESULTS

Nine articles met inclusion criteria: six cohort studies, two case series and one pilot study, totalling 230 patients. All but one article reported the effects of rituximab, the other those of belimumab. Overall, patients had active disease refractory to standard of care regimens using corticosteroids and immunosuppressants. Available evidence for rituximab demonstrated improvements in disease activity, complement levels and anti-dsDNA titres accompanying a steroid-sparing effect.

CONCLUSION

Rituximab can be considered an effective treatment in juvenile-onset systemic lupus erythematosus patients with severe disease manifestations and/or refractory disease. Based on current evidence, use of belimumab in juvenile-onset systemic lupus erythematosus patients cannot be recommended. The long-term safety of these biological agents remains uncertain. Further prospective studies, ideally robust randomized controlled trials, are urgently needed to obtain more accurate data on the effectiveness and long-term safety of rituximab, belimumab and other biologics in juvenile-onset systemic lupus erythematosus.

Cytokine profile in childhood-onset systemic lupus erythematosus: a cross-sectional and longitudinal study

Childhood-onset systemic lupus erythematosus (cSLE) exhibits an aggressive clinical phenotype and severe complications. This could be due to a pro-inflammatory cytokine milieu. Therefore, we determined plasma levels of Th1 (IL-2, IFN-γ, TNF), Th2 (IL-4), Th17 (IL-17A, IL-6), and Treg (IL-10) cytokines in a cohort of cSLE patients and healthy controls, and we evaluated the association between these cytokines and disease activity. We conducted a cross-sectional study with 51 cSLE patients from two pediatric rheumatology services. Ten cSLE patients participated in a longitudinal follow-up study. Blood samples were collected from the same patient during active and inactive disease. Disease activity was evaluated according to SLE Disease Activity Index 2000 (SLEDAI-2K). Cytokines levels were measured by cytometric bead array technique. cSLE patients had higher IL-6 (P<0.001) and IL-10 (P<0.001) levels than healthy controls. Patients with active disease had higher IL-6 and IL-10 levels than patients with inactive disease (P=0.001 and P=0.014, respectively) and the control group (both P<0.001). IL-6 (P=0.022), IL-10 (P=0.013), and IL-17A (P=0.041) levels were significantly higher during active than inactive disease. Linear regression analysis revealed IL-6 (P=0.002, 95%CI=0.006-0.025) and IL-10 (P=0.01 95%CI=0.021-0.150) as independent factors for increased SLEDAI-2K. IL-6, IL-10, and IL-17A are candidate biomarkers for disease activity in cSLE patients. This is the first longitudinal study to support their pivotal role in the pathogenesis of the disease.

Pharmacological Management of Childhood-Onset Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a rare, severe, multisystem autoimmune disorder. Childhood-onset SLE (cSLE) follows a more aggressive course with greater associated morbidity and mortality than adult-onset SLE. Its aetiology is yet to be fully elucidated. It is recognised to be the archetypal systemic autoimmune disease, arising from a complex interaction between the innate and adaptive immune systems. Its complexity is reflected by the fact that there has been only one new drug licensed for use in SLE in the last 50 years. However, biologic agents that specifically target aspects of the immune system are emerging. Immunosuppression remains the cornerstone of medical management, with glucocorticoids still playing a leading role. Treatment choices are led by disease severity. Immunosuppressants, including azathioprine and methotrexate, are used in mild to moderate manifestations. Mycophenolate mofetil is widely used for lupus nephritis. Cyclophosphamide remains the first-line treatment for patients with severe organ disease. No biologic therapies have yet been approved for cSLE, although they are being used increasingly as part of routine care of patients with severe lupus nephritis or with neurological and/or haematological involvement. Drugs influencing B cell survival, including belimumab and rituximab, are currently undergoing clinical trials in cSLE. Hydroxychloroquine is indicated for disease manifestations of all severities and can be used as monotherapy in mild disease. However, the management of cSLE is hampered by the lack of a robust evidence base. To date, it has been principally guided by best-practice guidelines, retrospective case series and adapted adult protocols. In this pharmacological review, we provide an overview of current practice for the management of cSLE, together with recent advances in new therapies, including biologic agents.

Subclinical pulmonary abnormalities in childhood-onset systemic lupus erythematosus patients

Objective

The aims of this study were to analyze the pulmonary function of childhood-onset systemic lupus erythematosus (cSLE) patients and to identify possible correlations between the high-resolution computed chest tomography (HRCT) score, disease activity, disease cumulative damage, and the participants’ quality of life.

Methods

Forty cSLE patients, median age: 14.1 years (range: 7.4–17.9), underwent spirometry and plethysmography. Carbon monoxide diffusing capacity (DLCO), HRCT, disease activity, disease cumulative damage, and quality of life were assessed.

Results

Pulmonary abnormalities were evident in 19/40 (47.5%) cSLE patients according to spirometry/DLCO. Forced expired volume in one second (FEV1%) was the parameter most affected (30%). The HRCT showed some abnormality in 22/30 patients (73%), which were minimal in 43%. Signs of airway affects were found in 50%. Twelve patients were hospitalized due to cSLE-related pulmonary complications before the study began (median discharge: 2.1 years earlier). Total lung capacity (TLC%), vital capacity (VC%), forced vital capacity (FVC%), and FEV1% were significantly lower in the group with hospitalization compared to the group without hospitalization ( p = 0.0025, p = 0.0022, p = 0.0032, and p = 0.0004, respectively). Of note, DLCO was positively correlated with disease duration ( r = +0.4; p = 0.01). The HRCT-score was negatively correlated with FEV1/VC ( r = −0.63; p = 0.0002), FEV1 ( r = −0.54; p = 0.018), FEF25%–75% ( r = −0.67; p < 0.0001), and HRCT-score was positively correlated with resistance ( r = +0.49; p = 0.0056).

Conclusions

Almost half of patients with cSLE had subclinical pulmonary abnormalities, especially airway abnormalities. The cSLE-related pulmonary complications seem to determine long-term functional damage.