Are serum autoantibodies associated with brain changes in systemic lupus erythematosus? MRI data from the Leiden NP-SLE cohort

Impairment of white matter microstructure and structural network in patients with systemic lupus erythematosus

OBJECTIVE

The study aimed to investigate the damage of white matter (WM) microstructure and structural network in patients with systemic lupus erythematosus (SLE) using diffusion tensor imaging.

METHODS

Tract-based spatial statistics (TBSS) were used to compare the difference in WM fractional anisotropy (FA) between SLE and HCs groups. The differences in WM networks between groups are compared using graph theory. The correlation between clinical data and SLE abnormal WM structure and network was analysed.

RESULTS

The sample included 140 SLE patients and 111 healthy controls (HCs). Due to data missing, excessive head movement amplitude, failure of quality control and other reasons, 127 cases of SLE (103 females, mean age 29.84 years (SD 7.00), median years of education 12.00, interquartile range(9.00,15.00) and a median course of disease (month) 12.00, interquartile range (3.00,24.00)) and 102 cases of HCs (76 females, mean age 30.63 years (SD 7.24), median years of education 15.00, interquartile range(12.00,16.00)) were finally included in the study. The FA values of 5 clusters involving the right retrolenticular part of the internal capsule (RLIC), the genu of corpus callosum (GCC), the body of corpus callosum, the splenium of corpus callosum (SCC), were significantly lower in the SLE group compared to the HCs (P < 0.05 with threshold-free cluster enhancement corrected). The SLEDAI showed a negative correlation with FA in GCC, and HAMD showed a negative correlation with FA in SCC and right RLIC (P < 0.05). Regarding network indicators, Cp, Eglob, and Eloc were significantly decreased, while Lp was significantly increased in the SLE group. The degree centrality (DC) of 6 brain regions and the Enodal of 17 regions were significantly lower in the SLE group. SLEDAI showed a negative correlation with the area under the curve (AUC) of DC and Enodal in the left inferior frontal gyrus triangular (q < 0.05 with false discovery rate corrected), while MMSE showed a positive correlation with the Enodal in the left hippocampus (P < 0.05).

CONCLUSION

The study concludes that changes in WM microstructure and its structural network may contribute to the development of severe neuropsychiatric symptoms in SLE patients. These changes may be the basis of brain damage that leads to the development of NPSLE from SLE without major neuropsychiatric manifestations.

VPS13C and STING expression in neuropsychiatric systemic lupus erythematosus: unveiling an unbreached territory

OBJECTIVES

To measure the expression level of the vacuolar protein sorting 13 (VPS13) gene and stimulator of interferon genes (STING) in patients with SLE with and without reported neuropsychiatric symptoms to establish their possible role in the pathogenesis of neuropsychiatric SLE (NPSLE).

METHODS

This study included 100 subjects: 50 patients diagnosed with SLE and 50 age-matched and sex-matched healthy participants as the control group. The patients with SLE were further subdivided into NPSLE and non-NPSLE groups. All the subjects underwent rheumatological, neurological and psychological evaluation, MRI, VPS13C gene and STING expression assessment via quantitative real-time PCR.

RESULTS

Seventy-eight per cent of the SLE group were classified as non-NPSLE, and 22% were classified as NPSLE. Positive MRI results were found in 55% of the patients with NPSLE and 7.7% of the patients without NPSLE.VPS13C expression levels were decreased in the patients with SLE compared with the control (p<0.001), while STING expression levels showed higher levels in the patients in comparison with the control (p<0.001). Both markers showed significant differences between the MRI-positive and MRI-negative groups.At a cut-off value of 0.225 for the VPS13C assessment and a cut-off value of 3.15 for STING expression, both markers were able to distinguish patients with NPSLE from those who were non-NPSLE; however, VPS13C performed better.

CONCLUSION

The VPS13C expression levels were decreased in patients with NPSLE compared with patients without NPSLE, while STING expression levels showed higher levels in NPSLE. Both were associated with the MRI findings. To distinguish patients with NPSLE from those without it, the VPS13C assessment performed better.

Prediction model for developing neuropsychiatric systemic lupus erythematosus in lupus patients

OBJECTIVE

This study aimed to construct a predictive model for assessing the risk of development of neuropsychiatric systemic lupus erythematosus (NPSLE) among patients with SLE based on clinical, laboratory, and meteorological data.

METHODS

A total of 2232 SLE patients were included and were randomly assigned into training and validation sets. Variables such as clinical and laboratory data and local meteorological data were screened by univariate and least absolute shrinkage and selection operator (LASSO) logistic regression modelling. After 10-fold cross-validation, the predictive model was built by multivariate logistic regression, and a nomogram was constructed to visualize the risk of NPSLE. The efficacy and accuracy of the model were assessed by receiver operating characteristic (ROC) curve and calibration curve analysis. Net clinical benefit was assessed by decision curve analysis.

RESULTS

Variables that were included in the predictive model were anti-dsDNA, anti-SSA, lymphocyte count, hematocrit, erythrocyte sedimentation rate, pre-albumin, retinol binding protein, creatine kinase isoenzyme MB, Nterminal brain natriuretic peptide precursor, creatinine, indirect bilirubin, fibrinogen, hypersensitive C-reactive protein, CO, and mild contamination. The nomogram showed a broad prediction spectrum; the area under the curve (AUC) was 0.895 (0.858-0.931) for the training set and 0.849 (0.783-0.916) for the validation set.

CONCLUSION

The model exhibits good predictive performance and will confer clinical benefit in NPSLE risk calculation. Key Points • Clinical, laboratory, and meteorological data were incorporated into a predictive model for neuropsychiatric systemic lupus erythematosus (NPSLE) in SLE patients. • Anti-dsDNA, anti-SSA, LYM, HCT, ESR, hsCRP, IBIL, PA, RBP, CO, Fib, NT-proBNP, Crea, CO, and mild contamination are predictors of the development of NPSLE and may have potential for research. • The nomogram has good predictive performance and clinical value and can be used to guide clinical diagnosis and treatment.

Cerebrovascular disease in patients with antiphospholipid antibody syndrome: a transcranial Doppler and magnetic resonance imaging study

Objective

Transcranial Doppler (TCD) and brain MRI may be useful in evaluating patients with APS, helping to stratify the risk of cerebrovascular ischaemic events in this population. This study aimed to assess the frequency of brain MRI abnormalities in patients with primary antiphospholipid syndrome, secondary antiphospholipid syndrome and SLE and correlate to TCD findings.

Methods

The study, conducted over four years at two autoimmune disease referral centres, included 22 primary antiphospholipid syndrome patients, 24 secondary antiphospholipid syndrome patients, 27 SLE patients without APS and 21 healthy controls. All participants underwent TCD to assess cerebral haemodynamics, detect microembolic signals and evaluate right-to-left shunts, followed by brain MRI and magnetic resonance angiography. MRI scans were reviewed for acute microembolism, localized cortical infarctions, border infarctions, lacunar infarctions, ischaemic lesions, white matter hyperintensity, micro and macro haemorrhages and arterial stenosis ≥50% of the cervical carotid artery, by two neuroradiologists blinded to the clinical data.

Results

Brain MRI findings were similar between the groups, except for lacunar infarction, more frequent in patients with secondary antiphospholipid syndrome (P = 0.022). Patients with intracranial stenosis detected by TCD had a higher frequency of territorial infarction (40% vs 7.5%, P = 0.02), lacunar (40% vs 11.3%, P = 0.075) and border zone infarcts (20% vs 1.9%, P = 0.034).

Conclusions

Patients with intracranial stenosis presented a higher frequency of territorial, lacunar and border zone infarcts, suggesting that evaluating the intracranial vasculature should not be neglected in patients with APS and stroke.

Correlation between the changes of brain amplitude of low-frequency fluctuation and cognitive impairment in patients with neuropsychiatric lupus

PURPOSE

To explore the relationship between brain function changes and clinical serological indicators and behavioral cognitive assessment in patients with neuropsychiatric systemic lupus erythematosus (NPSLE), and understand the pathogenesis of NPSLE from the perspective of imaging.

METHODS

The resting-state functional imaging data, clinical serological, and behavioral cognitive assessment scores of 28 patients with NPSLE and 22 healthy controls (HC) were prospectively collected. The resting-state amplitude of low-frequency fluctuation (ALFF) values obtained from the analysis and processing were correlated with the serological data and behavioral cognitive assessment scores to determine the relationship between these data.

RESULTS

The average age of the patients of the NPSLE group was older than that of the HC group; significant differences in education level, Auditory Verbal Learning Test Hua Shan Version (AVLT-H), and Trail Making Test scores were observed between the two groups. The NPSLE group demonstrated increased brain activity in the insula, precentral gyrus, and superior temporal gyrus, and decreased brain activity in the superior parietal gyrus. The ALFF value of the insula positively correlated with the Anti-β2gp1 antibody and negatively correlated with the anti-nucleosome antibody and the AVL-recall (RC) score. The ALFF of the precentral gyrus negatively correlated with the AVL-immediate recall (I). The ALFF value of the superior temporal gyrus negatively correlated with the AVL-RC score. The left superior parietal gyrus positively correlated with the c-reactive protein. The right superior parietal gyrus positively correlated with the System Lupus Erythematosus Disease Activity Index and negatively correlated with the AVL-I score.

CONCLUSION

Patients with NPSLE show different brain activity changes in different brain regions, and the abnormal brain regions are correlated with certain lupus antibodies, inflammatory factors, and cognitive assessment, thereby suggesting that the correlation between the three could provide novel insights into the pathogenesis of NPSLE.

MRI BrainAGE demonstrates increased brain aging in systemic lupus erythematosus patients

Introduction

Systemic lupus erythematosus (SLE) is an autoimmune connective tissue disease affecting multiple organs in the human body, including the central nervous system. Recently, an artificial intelligence method called BrainAGE (Brain Age Gap Estimation), defined as predicted age minus chronological age, has been developed to measure the deviation of brain aging from a healthy population using MRI. Our aim was to evaluate brain aging in SLE patients using a deep-learning BrainAGE model.

Methods

Seventy female patients with a clinical diagnosis of SLE and 24 healthy age-matched control females, were included in this post-hoc analysis of prospectively acquired data. All subjects had previously undergone a 3 T MRI acquisition, a neuropsychological evaluation and a measurement of neurofilament light protein in plasma (NfL). A BrainAGE model with a 3D convolutional neural network architecture, pre-trained on the 3D-T1 images of 1,295 healthy female subjects to predict their chronological age, was applied on the images of SLE patients and controls in order to compute the BrainAGE. SLE patients were divided into 2 groups according to the BrainAGE distribution (high vs. low BrainAGE).

Results

BrainAGE z-score was significantly higher in SLE patients than in controls (+0.6 [±1.1] vs. 0 [±1.0], p = 0.02). In SLE patients, high BrainAGE was associated with longer reaction times (p = 0.02), lower psychomotor speed (p = 0.001) and cognitive flexibility (p = 0.04), as well as with higher NfL after adjusting for age (p = 0.001).

Conclusion

Using a deep-learning BrainAGE model, we provide evidence of increased brain aging in SLE patients, which reflected neuronal damage and cognitive impairment.

Clinical characteristics and prognosis in systemic lupus erythematosus-associated pulmonary arterial hypertension based on consensus clustering and risk prediction model

BACKGROUND

Pulmonary arterial hypertension (PAH) is a severe complication of systemic lupus erythematosus (SLE). This study aims to explore the clinical characteristics and prognosis in SLE-PAH based on consensus clustering and risk prediction model.

METHODS

A total of 205 PAH (including 163 SLE-PAH and 42 idiopathic PAH) patients were enrolled retrospectively based on medical records at the First Affiliated Hospital of Zhengzhou University from July 2014 to June 2021. Unsupervised consensus clustering was used to identify SLE-PAH subtypes that best represent the data pattern. The Kaplan-Meier survival was analyzed in different subtypes. Besides, the least absolute shrinkage and selection operator combined with Cox proportional hazards regression model were performed to construct the SLE-PAH risk prediction model.

RESULTS

Clustering analysis defined two subtypes, cluster 1 (n = 134) and cluster 2 (n = 29). Compared with cluster 1, SLE-PAH patients in cluster 2 had less favorable levels of poor cardiac, kidney, and coagulation function markers, with higher SLE disease activity, less frequency of PAH medications, and lower survival rate within 2 years (86.2% vs. 92.8%) (P < 0.05). The risk prediction model was also constructed, including older age at diagnosis (≥ 38 years), anti-dsDNA antibody, neuropsychiatric lupus, and platelet distribution width (PDW).

CONCLUSIONS

Consensus clustering identified two distinct SLE-PAH subtypes which were associated with survival outcomes. Four prognostic factors for death were discovered to construct the SLE-PAH risk prediction model.

Neuropsychiatric involvement in juvenile-onset systemic lupus erythematosus: A multicenter study

INTRODUCTION

Neuropsychiatric (NP) involvement is a restricted area in juvenile-onset systemic lupus erythematosus (jSLE).

AIM

To investigate the prevalence, demographic and clinical features, and outcomes of the neurological involvement in the Turkish jSLE population.

METHODS

This study was based upon 24 referral centers' SLE cohorts, multicenter and multidisciplinary network in Turkey. Patient data were collected by a case report form which was standardized for NP definitions according to American Collage of Rheumatology (ACR). Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) neuropsychiatric part was used to determine NP damage. Variables were evaluated Ward's hierarchical clustering analyses, univariate, and multivariate logistic regression analyses.

RESULTS

A hundred forty-nine of 1107 jSLE patients had NP involvement (13.5%). The most common NPSLE findings were headache (50.3%), seizure (38.3%), and acute confusional state (33.6%). Five clusters were identified with all clinical and laboratory findings. The first two clusters involved neuropathies, demyelinating diseases, aseptic meningitis, and movement disorder. Cluster 3 involved headache, activity markers and other SLE involvements. Idiopathic intracranial hypertension, cerebrovascular disease, cognitive dysfunction, psychiatric disorders and SLE antibodies were in the fourth, and acute confusional state was in the fifth cluster. In multivariate analysis, APA positivity; OR: 2.820, (%95CI: 1.002-7.939), P: 0,050, plasmapheresis; OR: 13.804 (%95CI: 2.785-68.432), P: 0,001, SLEDAI scores; OR: 1.115 (%95CI: (1.049-1.186), P: 0,001 were associated with increased risk for neurologic sequelae.

CONCLUSION

We detected the prevalence of juvenile NPSLE manifestations in Turkey. We have identified five clusters that may shed light pathogenesis, treatment and prognosis of NP involvements. We also determined risk factors of neurological sequelae. Our study showed that new definitions NP involvements and sequelae for childhood period are needed.

Brain-reactive autoantibodies in neuropsychiatric systemic lupus erythematosus

Introduction

The pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE) is widely unknown, and the role of autoantibodies is still undetermined.

Methods

To identify brain-reactive autoantibodies possibly related to NPSLE, immunofluorescence (IF) and transmission electron microscopy (TEM) on rat and human brains were performed. ELISA was used to reveal the presence of known circulating autoantibodies, while western blot (WB) was applied to characterize potential unknown autoantigen(s).

Results

We enrolled 209 subjects, including patients affected by SLE (n=69), NPSLE (n=36), Multiple Sclerosis (MS, n=22), and 82 age- and gender-matched healthy donors (HD). Autoantibody reactivity by IF was observed in almost the entire rat brain (cortex, hippocampus, and cerebellum) using sera from NPSLE and SLE patients and was virtually negative in MS and HD. NPSLE showed higher prevalence (OR 2.4; p = 0.047), intensity, and titer of brain-reactive autoantibodies than SLE patients. Most of the patient sera with brain-reactive autoantibodies (75%) also stained human brains. Double staining experiments on rat brains mixing patients' sera with antibodies directed against neuronal (NeuN) or glial markers showed autoantibody reactivity restricted to NeuN-containing neurons. Using TEM, the targets of brain-reactive autoantibodies were located in the nuclei and, to a lesser extent, in the cytoplasm and mitochondria. Given the high degree of colocalization between NeuN and brain-reactive autoantibodies, we assumed NeuN was a possible autoantigen. However, WB analysis with HEK293T cell lysates expressing or not expressing the gene encoding for NeuN protein (RIBFOX3) showed that patients' sera carrying brain-reactive autoantibodies did not recognize the NeuN corresponding band size. Among the panel of NPSLE-associated autoantibodies (e.g., anti-NR2, anti-P-ribosomal protein, antiphospholipid) investigated by ELISA assay, only the anti-β2-glycoprotein-I (aβ2GPI) IgG was exclusively found in those sera containing brain-reactive autoantibodies.

Conclusion

In conclusion, SLE and NPSLE patients possess brain-reactive autoantibodies but with higher frequency and titers found in NPSLE patients. Although many target antigens of brain-reactive autoantibodies are still undetermined, they likely include β2GPI.

Mouse models, antibodies, and neuroimaging: Current knowledge and future perspectives in neuropsychiatric systemic lupus erythematosus (NPSLE)

As a chronic autoimmune disease systemic lupus erythematosus (SLE) can also affect the central and the peripheral nervous system causing symptoms which are summed up as neuropsychiatric systemic lupus erythematosus (NPSLE). These symptoms are heterogenous including cognitive impairment, seizures, and fatigue, leading to morbidity or even mortality. At present, little is known about the pathophysiological processes involved in NPSLE. This review focuses on the current knowledge of the pathogenesis of NPSLE gained from the investigation of animal models, autoantibodies, and neuroimaging techniques. The antibodies investigated the most are anti-ribosomal P protein antibodies (Anti-rib P) and anti-N-Methyl-D-Aspartic Acid Receptor 2 antibodies (Anti-NR2), which represent a subpopulation of anti-dsDNA autoantibodies. Experimental data demonstrates that Anti-rib P and Anti-NR2 cause different neurological pathologies when applied intravenously (i.v.), intrathecally or intracerebrally in mice. Moreover, the investigation of lupus-prone mice, such as the MRL/MpJ-Faslpr/lpr strain (MRL/lpr) and the New Zealand black/New Zealand white mice (NZB × NZW F1) showed that circulating systemic antibodies cause different neuropsychiatric symptoms compared to intrathecally produced antibodies. Furthermore, neuroimaging techniques including magnetic resonance imaging (MRI) and positron emission tomography (PET) are commonly used tools to investigate structural and functional abnormalities in NPSLE patients. Current research suggests that the pathogenesis of NPSLE is heterogenous, complex and not yet fully understood. However, it demonstrates that further investigation is needed to develop individual therapy in NPSLE.

Bidirectional Association Between Obsessive-Compulsive Disorder and Systemic Autoimmune Diseases Among Probands and Unaffected Siblings: A Nationwide Population-Based Study

OBJECTIVE

Studies have reported a biological link between obsessive-compulsive disorder (OCD) and systemic autoimmune disease (SAID). However, whether the unaffected siblings of patients with OCD or SAID are more likely to develop subsequent SAID or OCD later in life remains unclear.

METHODS

We examined the Taiwan National Health Insurance Research Database data of 17,135 patients with SAID, 30,672 unaffected siblings, and 467,211 non-SAID reference subjects born before 2000 for subsequent OCD during 1996-2011 and those of 25,364 patients with OCD, 42,546 unaffected siblings, and 654,207 non-OCD reference subjects to identify subsequent SAID during 1996-2011.

RESULTS

Patients with SAID (odds ratio = 1.74, 95% confidence interval = 1.31-2.31) and unaffected siblings (1.25, 0.92-1.70) were more likely to develop OCD later in life than the non-SAID reference group. Moreover, patients with OCD (odds ratio = 1.53, 95% confidence interval = 1.15-2.05) and unaffected siblings (1.51, 1.21-1.87) were more likely to develop any form of SAID during the follow-up than the non-OCD reference group.

CONCLUSIONS

The bidirectional association of OCD and SAID between probands and siblings may indicate a familial coaggregation of these two conditions. Additional studies elucidating the genetic and environmental mechanisms underlying this coaggregation are warranted.

Autoimmune diseases of the brain, imaging and clinical review

There is an extensive spectrum of autoimmune entities that can involve the central nervous system, which has expanded with the emergence of new imaging modalities and several clinicopathologic entities. Clinical presentation is usually non-specific, and imaging has a critical role in the workup of these diseases. Immune-mediated diseases of the brain are not common in daily practice for radiologists and, except for a few of them such as multiple sclerosis, there is a vague understanding about differentiating them from each other based on the radiological findings. In this review, we aim to provide a practical diagnostic approach based on the unique radiological findings for each disease. We hope our diagnostic approach will help radiologists expand their basic understanding of the discussed disease entities and narrow the differential diagnosis in specific clinical scenarios. An understanding of unique imaging features of these disorders, along with laboratory evaluation, may enable clinicians to decrease the need for tissue biopsy.

White matter microstructure alterations in systemic lupus erythematosus: A preliminary coordinate-based meta-analysis of diffusion tensor imaging studies

BACKGROUND

Systemic lupus erythematosus is often accompanied with neuropsychiatric symptoms. Neuroimaging evidence indicated that microstructural white matter (WM) abnormalities play role in the neuropathological mechanism. Diffusion tensor imaging (DTI) studies allows the assessment of the microstructural integrity of WM tracts, but existing findings were inconsistent. This present study aimed to conduct a coordinate-based meta-analysis (CBMA) to identify statistical consensus of DTI studies in SLE.

METHODS

Relevant studies that reported the differences of fractional anisotropy (FA) between SLE patients and healthy controls (HC) were searched systematically. Only studies reported the results in Talairach or Montreal Neurological Institute (MNI) coordinates were included. The anisotropic effect size version of signed differential mapping (AES-SDM) was applied to detect WM alterations in SLE.

RESULTS

Totally, five studies with seven datasets which included 126 patients and 161 HC were identified. The pooled meta-analysis demonstrated that SLE patients exhibited significant FA reduction in the left striatum and bilateral inferior network, mainly comprised the corpus callosum (CC), bilateral inferior fronto-occipital fasciculus (IFOF), bilateral anterior thalamic projections, bilateral superior longitudinal fasciculus (SLF), left inferior longitudinal fasciculus (ILF), and left insula. No region with higher FA was identified.

CONCLUSIONS

Disorders of the immune system might lead to subtle WM microstructural alterations in SLE, which might be related with cognitive deficits or emotional distress symptoms. This provides a better understanding of the pathological mechanism of microstructural brain abnormalities in SLE.

The high prevalence of abnormal MRI findings in non-neuropsychiatric patients with persistently positive antiphospholipid antibodies

OBJECTIVES

Thrombosis occurring in the central nerve system is common in antiphospholipid syndrome (APS) patients, leading to neuropsychiatric symptoms. We investigated the prevalence of silent brain abnormalities on magnetic resonance imaging (MRI) in primary antiphospholipid syndrome (PAPS) patients and antiphospholipid antibodies (aPL) carriers and assessed the association between the vascular risk factors, aPL profile, clinical manifestations, and MRI abnormalities.

METHODS

We consecutively included 44 PAPS patients, 24 aPL carriers and 23 healthy controls with comparable age and gender in a single-center, observational cross-sectional study. None of the patients had a history of stroke, TIA, migraine, dementia, epilepsy and bipolar disorders. On cerebral MRI, we assessed the imaging features and location of abnormality. Multivariate analysis was performed to identify the risk factors contributing to the MRI abnormalities.

RESULTS

38 (55.88%) patients persisted abnormal MRI findings, while only one healthy control showed some abnormalities in the MR findings. Lacunes were the most frequent MRI abnormality in aPL (+) group (31/68, 45.59%), which were followed by white matter hyperintensities (20/68, 29.41%). In all study population, age (OR = 1.086, p= 0.016) and LA positivity (OR = 5.191, p= 0.002) were the independent associated factors with the brain MRI abnormalities. When analyzed only in the aPL (+) group, age (OR = 1.116, p= 0.007), female gender (OR = 7.519, p= 0.025) and thrombocytopenia (OR = 8.336, p= 0.047) were the significant independent risk factors with abnormal MRI.

CONCLUSIONS

PAPS patients and aPL carriers showed a high prevalence of brain MRI abnormalities, indicating an increased cerebrovascular risk, which emphasized attention to silent cerebral lesions in persistently aPL positive patients.

Neuropsychiatric involvement in systemic lupus erythematosus: A review

The neuropsychiatric involvement in systemic lupus erythematosus (NPSLE) is a challenge for clinicians, both at a diagnostic and therapeutic level. Although in 1999 the American College of Rheumatology (ACR) proposed a set of definitions for 19 NPSLE syndromes, with the intention of homogenizing the terminology for research purposes and clinical practice, the prevalence of NPSLE varies widely according to different series and is estimated to be between 37 and 95%. This is due to multiple factors such as the unalike definitions used, the diverse design of the studies, type of population, race, type and severity of symptoms, and follow-up of the different cohorts of patients with SLE. In recent years, some authors have tried excluding minor neuropsychiatric manifestations in order to try to reduce this wide variation in the prevalence of NPSLE since they are very prevalent in the general population; others authors have developed various models for the attribution of neuropsychiatric events to SLE that can assist clinicians in this diagnostic process, and finally, some authors developed and validated in 2014 a new algorithm based on the definitions of the ACR that includes the evaluation of the patient's lupus activity together with imaging techniques and the analysis of cerebrospinal fluid (CSF), with the aim of trying to differentiate the true neuropsychiatric manifestations attributable to SLE. In 2010, the European League Against Rheumatism (EULAR) developed recommendations for the management of NPSLE. We found abundant literature published later where, in addition to the recommendations for the management of the 19 NPSLE syndromes defined by the ACR, additional recommendations are given for other neurological and/or psychiatric syndromes, conditions, and complications that have been associated to SLE in recent years. We review below the diagnostic and therapeutic management of the different entities.

Advanced neuroimaging in neuropsychiatric systemic lupus erythematosus

Neuropsychiatric lupus (NPSLE) comprises a disparate collection of syndromes affecting the central and peripheral nervous systems. Progress in the attribution of neuropsychiatric syndromes to SLE-related mechanisms and development of targeted treatment strategies has been impeded by a lack of objective imaging biomarkers that reflect specific neuropsychiatric syndromes and/or pathologic mechanisms. The present review addresses recent publications of neuroimaging techniques in NPSLE.

Neurofilament light is a biomarker of brain involvement in lupus and primary Sjögren's syndrome

Background

To test the hypothesis that neurofilament light (NfL) in CSF is a biomarker of CNS involvement in patients with systemic lupus erythematosus (SLE) and primary Sjögren’s syndrome (pSS), we measured NfL in CSF from 52 patients with lupus and 54 with pSS and explored associations with clinical, structural, immunological and biochemical abnormalities.

Methods

In CSF, we measured NfL, anti-P antibodies, protein S100B and TWEAK by ELISA and anti-NR2 antibodies by electrochemiluminescence. Anti-phospholipid antibodies and routine immunological tests were performed in blood. IgG and albumin were measured in CSF and serum for assessment of the blood–brain barrier function (Q-albumin) and intrathecal IgG production (IgG index). Cerebral MRI and neuropsychological testing were performed.

Results

A multivariable regression model showed that increasing CSF anti-NR2 antibody levels were associated with increasing NfL levels in patients with SLE (B 1.27, 95% CI 0.88–1.65, p < 0.001). Age contributed significantly in the model (B 0.04, 95% CI 0.03–0.05, p < 0.001). Similar findings were observed in the pSS group. Adjusted for age and sex, no associations were found between NfL levels and any MRI data. In SLE patients, higher NfL concentrations were associated with impairments in psychomotor speed and motor function, and in pSS with motor dysfunction. These associations remained in multivariable regression models.

Conclusions

Increased concentration of NfL in CSF is a marker of cerebral involvement in patients with SLE and pSS, is strongly associated with the presence of anti-NR2 antibodies, and correlates with cognitive impairment in several domains.

Electronic supplementary material

Supplementary information is available for this paper at 10.1007/s00415-020-10290-y.

Advances in the diagnosis, pathogenesis and treatment of neuropsychiatric systemic lupus erythematosus

PURPOSE OF REVIEW

Diagnosing and treating neuropsychiatric systemic lupus erythematosus (NPSLE) remains challenging as the pathogenesis is still being debated. In this review, we discuss studies evaluating recent advances in diagnostic methods, pathogenic mediators and potential treatments.

RECENT FINDINGS

Screening tools used for neurodegenerative diseases were found to be both sensitive and moderately specific for cognitive dysfunction in NPSLE. Neuroimaging can be used to distinguish systemic lupus erythematosus (SLE) patients from healthy controls, but further refinement is needed to differentiate between lupus patients with and without neuropsychiatric manifestations. Elevated levels of specific molecules in the cerebrospinal fluid and/or serum, as well as the presence of certain autoantibodies, have been identified as potential biomarkers in attempts to facilitate a more accurate and objective diagnosis. Among such autoantibodies, anti-NR2 and anti-ribosomal P autoantibodies also have a pathogenic role, although newer studies demonstrate that blood-brain barrier damage may not always be required as previously believed. These and other observations, together with new evidence for disease attenuation after microglial modulation, suggest direct involvement of the central nervous system in NPSLE pathogenesis.

SUMMARY

Neuropsychiatric involvement of SLE includes a variety of symptoms that impact quality of life and patient prognosis. There have been recent advances in improving the diagnosis of NPSLE as well as in dissecting the underlying pathogenesis. The attenuation of neuropsychiatric disease in mouse models demonstrates the potential for targeted therapies, which are based on a clearer understanding of the pathogenesis of NPSLE. Further assessment of these treatments is required in NPSLE patients, as well as the potential use of neuroimaging to distinguish between SLE patients with or without neuropsychiatric manifestations.

Left Ventricular Systolic Function in Patients with Systemic Lupus Erythematosus and Its Association with Cardiovascular Events

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder with potential cardiovascular involvement. The aim of this study was to assess left ventricular (LV) systolic function in a large cohort of patients with SLE using standard echocardiographic measurements and global longitudinal strain (GLS) by two-dimensional speckle-tracking analysis. Furthermore, the association between echocardiographic parameters and the occurrence of cardiovascular events was assessed.

METHODS

A total of 102 patients with SLE (88% women; mean age, 43 ± 14 years) undergoing a dedicated multidisciplinary assessment were analyzed, including echocardiography, at the time of their first visit. A control group consisted of 50 age- and sex-matched healthy subjects.

RESULTS

Compared with control subjects, patients with SLE showed impaired LV systolic function on the basis of LV ejection fraction (51 ± 6% vs 62 ± 6%, P < .001) and by LV GLS (-15 ± 3% vs -19 ± 2%, P < .001). During a median follow-up period of 2 years (interquartile range, 1-6 years), 38 patients (37%) developed cardiovascular events. Kaplan-Meier survival curves showed that patients with SLE with more impaired LV GLS (on the basis of the median value of -15%) experienced higher cumulative rates of cardiovascular events compared with those with less impaired LV GLS (χ² = 8.292, log-rank P = .004). On multivariate Cox regression analysis, LV GLS demonstrated an independent association with cardiovascular events (hazard ratio, 2.171; 95% CI, 1.015-4.642; P = .046), whereas LV ejection fraction was not significantly associated with the outcome.

CONCLUSIONS

In patients with SLE, LV systolic function as measured by LV GLS is significantly impaired and associated with cardiovascular events, potentially representing a new tool to improve risk stratification in these patients.

Conventional brain magnetic resonance imaging in the longitudinal evaluation of newly diagnosed systemic lupus erythematosus patients: a retrospective analysis from a single-centre cohort

INTRODUCTION

Neuropsychiatric (NP) manifestations occur mostly in the early phases of the systemic lupus erythematosus (SLE) course. Nonspecific alterations are evident in conventional brain magnetic resonance imaging (MRI), regardless of clinically overt NP symptoms. The main aims of this study were to assess the prevalence of MRI abnormalities in newly diagnosed SLE, and to evaluate the impact of MRI changes during follow-up (FU) and the clinical course of NP symptoms.

MATERIALS AND METHODS

Newly diagnosed SLE patients with a baseline brain MRI and with available repeated MRI during FU were retrospectively evaluated. White-matter lesions and atrophy were recorded, comparing NPSLE and non-NPSLE patients. Cox proportional hazard models were used to compare NP events during FU with MRI data.

RESULTS

Forty-four patients were included, 22 with NP events attributed to SLE. The baseline MRI scan was abnormal in 21 patients (47.73%). New NP events occurred in 17 patients, and worsening was found in repeated MRIs in 12 (27.27%). A worsening of MRI was associated with higher occurrence of new NP events during FU (adjusted hazard ratio 3.946 (1.175-13.253)).

CONCLUSION

Baseline MRI is useful in patients with an early diagnosis of SLE, allowing comparison with subsequent scans. In our study, radiological worsening of repeated brain MRI was associated with new NP events.

A20/TNFAIP3 heterozygosity predisposes to behavioral symptoms in a mouse model for neuropsychiatric lupus

Background

Neuropsychiatric lupus (NPSLE) refers to the neurological and psychiatric manifestations that are commonly observed in patients with systemic lupus erythematosus (SLE). An important question regarding the pathogenesis of NPSLE is whether the symptoms are caused primarily by CNS-intrinsic mechanisms or develop as a consequence of systemic autoimmunity. Currently used spontaneous mouse models for SLE have already contributed significantly to unraveling how systemic immunity affects the CNS. However, they are less suited when interested in CNS primary mechanisms. In addition, none of these models are based on genes that are associated with SLE. In this study, we evaluate the influence of A20, a well-known susceptibility locus for SLE, on behavior and CNS-associated changes in inflammatory markers. Furthermore, given the importance of environmental triggers for disease onset and progression, the influence of an acute immunological challenge was evaluated.

Methods

Female and male A20 heterozygous mice (A20+/-) and wildtype littermates were tested in an extensive behavioral battery. This was done at the age of 10±2weeks and 24 ​± ​2 weeks to evaluate the impact of aging. To investigate the contribution of an acute immunological challenge, LPS was injected intracerebroventricularly at the age of 10±2weeks followed by behavioral analysis. Underlying molecular mechanisms were evaluated in gene expression assays on hippocampus and cortex. White blood cell count and blood-brain barrier permeability were analyzed to determine whether peripheral inflammation is a relevant factor.

Results

A20 heterozygosity predisposes to cognitive symptoms that were observed at the age of 10 ​± ​2 weeks and 24 ​± ​2 weeks. Young A20+/- males and females showed a subtle cognitive phenotype (10±2weeks) with distinct neuroinflammatory phenotypes. Aging was associated with clear neuroinflammation in female A20+/- mice only. The genetic predisposition in combination with an environmental stimulus exacerbates the behavioral impairments related to anxiety, cognitive dysfunction and sensorimotor gating. This was predominantly observed in females. Furthermore, signs of neuroinflammation were solely observed in female A20+/- mice. All above observations were made in the absence of peripheral inflammation and of changes in blood-brain barrier permeability, thus consistent with the CNS-primary hypothesis.

Conclusions

We show that A20 heterozygosity is a predisposing factor for NPSLE. Further mechanistic insight and possible therapeutic interventions can be studied in this mouse model that recapitulates several key hallmarks of the disease.

Downregulation of hippocampal NR2A/2B subunits related to cognitive impairment in a pristane-induced lupus BALB/c mice

Neuropsychiatric systemic lupus erythematosus (NPSLE) is associated with learning and memory deficit. Murine model of lupus induced by pristane in BALB/c mice is an experimental model that resembles some clinical and immunological SLE pathogenesis. Nevertheless, there is no experimental evidence that relates this model to cognitive dysfunction associated with NR2A/2B relative expression. To evaluate cognitive impairment related to memory deficits in a murine model of lupus induced by pristane in BALB/c mice related to mRNA relative expression levels of NR2A/2B hippocampal subunits in short and long-term memory task at 7 and 12 weeks after LPS exposition in a behavioral test with the use of Barnes maze. A total of 54 female BALB/c mice 8–12 weeks old were included into 3 groups: 7 and 12 weeks using pristane alone (0.5 mL of pristane) by a single intraperitoneal (i.p.) injection. A control group (single i.p. injection of 0.5 mL NaCl 0.9%) and pristane plus LPS exposure using single i.p. pristane injection and LPS of E. coli O55:B5, in a dose of 3mg/kg diluted in NaCl 0.9% 16 weeks post-pristane administration. To determine cognitive dysfunction, mice were tested in a Barnes maze. Serum anti-Sm antibodies and relative expression of hippocampal NR2A/2B subunits (GAPDH as housekeeping gene) with SYBR green quantitative reverse transcription polymerase chain reaction and 2^-ΔΔC_T method were determined in the groups. Downregulation of hippocampal NR2A subunit was more evident than NR2B in pristane and pristane+LPS at 7 and 12 weeks of treatment and it is related to learning and memory disturbance assayed by Barnes maze. This is the first report using the murine model of lupus induced by pristane that analyzes the NMDA subunit receptors, finding a downregulation of NR2A subunit related to learning and memory disturbance being more evident when they were exposed to LPS.

Functional Improvement after Taking Rehabilitation Program in Cerebellar Ataxia in a Patient with Systemic Lupus Erythematosus: a Case Report

Cerebellar involvement in systemic lupus erythematosus (SLE) is rare, occurring in less than 2% of cases, with cerebellar atrophy on brain imaging even rarer. We describe a case of cerebellar atrophy in a patient with a history of SLE who underwent an intensive rehabilitation program and achieved functional improvement. A 26-years-old female with SLE felt difficult in balancing as well as dizziness and she took magnetic resonance imaging which showed cerebellar atrophy and positron emission tomography-computed tomography which showed markedly decreased signal intensity at bilateral temporal, parietal lobes, cerebellum and moderately at bilateral frontal lobes. A neurological examination showed bilateral nystagmus, intention tremor, bilateral dysmetria, and bilateral dysdiadochokinesia. Prior to the rehabilitation program, the patient's scores on the Berg Balance Scale (BBS) and Modified Barthel Index (MBI) were 4/56 and 37/100, respectively. The patient was hospitalized twice for rehabilitation treatment, which consisted of physical therapy, occupational therapy, therapeutic pool therapy, and robotic-assisted gait training. At discharge, the patient's BBS score was 9/56, and her MBI score was 46/100, and she was able to walk more than 20 m using an anterior walker. In the final 2 weeks before discharge, the patient was trained in the use of an electric wheelchair for outdoor activity.