Multisequence magnetic resonance imaging study of neuropsychiatric systemic lupus erythematosus

Cerebral Microstructure Analysis by Diffusion-Based MRI in Systemic Lupus Erythematosus: Lessons Learned and Research Directions

Diffusion-based magnetic resonance imaging (MRI) studies, namely diffusion-weighted imaging (DWI) and diffusion-tensor imaging (DTI), have been performed in the context of systemic lupus erythematosus (SLE), either with or without neuropsychiatric (NP) involvement, to deepen cerebral microstructure alterations. These techniques permit the measurement of the variations in random movement of water molecules in tissues, enabling their microarchitecture analysis. While DWI is recommended as part of the initial MRI assessment of SLE patients suspected for NP involvement, DTI is not routinely part of the instrumental evaluation for clinical purposes, and it has been mainly used for research. DWI and DTI studies revealed less restricted movement of water molecules inside cerebral white matter (WM), expression of a global loss of WM density, occurring in the context of SLE, prevalently, but not exclusively, in case of NP involvement. More advanced studies have combined DTI with other quantitative MRI techniques, to further characterize disease pathogenesis, while brain connectomes analysis revealed structural WM network disruption. In this narrative review, the authors provide a summary of the evidence regarding cerebral microstructure analysis by DWI and DTI studies in SLE, focusing on lessons learned and future research perspectives.

Proton magnetic resonance spectroscopy (1H-MRS) in rheumatic autoimmune diseases: A systematic review

BACKGROUND/PURPOSE

Proton magnetic resonance spectroscopy (¹H-MRS) has been shown to be an important non-invasive tool to quantify neuronal loss or damage in the investigation of central nervous system (CNS) disorders. The purpose of this article is to discuss the clinical utility of ¹H-MRS in determining CNS involvement in individuals with rheumatic autoimmune diseases.

METHODS

This study is a systematic review of the literature, conducted during the month of November and December of 2019 of articles published in the last 16 years (2003-2019). The search for relevant references was done through the exploration of electronic databases (PubMed/Medline and Embase). We searched for studied including systemic lupus erythematosus (SLE), systemic sclerosis (SSc), juvenile idiopathic arthritis, rheumatoid arthritis (RA), psoriasis, Sjögren's syndrome (pSS), vasculitis and Behçet. Only studies published after 2003 and with more than 20 patients were included.

RESULTS

We included 26 articles. NAA/Cr ratios were significant lower and Cho/Cr ratios increased in several brain regions in SLE, SS, RA, SSc. Associations with disease activity, inflammatory markers, CNS manifestations and comorbidities was variable across studies and diseases.

CONCLUSION

The presence of neurometabolite abnormalities in patients without ouvert CNS manifestations, suggests that systemic inflammation, atherosclerosis or abnormal vascular reactivity may be associated with subclinical CNS manifestations. MRS may be a usefull non-invasive method for screening patients with risk for CNS manifestations.

Laboratory and Neuroimaging Biomarkers in Neuropsychiatric Systemic Lupus Erythematosus: Where Do We Stand, Where To Go?

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by multi-systemic involvement. Nervous system involvement in SLE leads to a series of uncommon and heterogeneous neuropsychiatric (NP) manifestations. Current knowledge on the underlying pathogenic processes and their subsequent pathophysiological changes leading to NP-SLE manifestations is incomplete. Several putative laboratory biomarkers have been proposed as contributors to the genesis of SLE-related nervous system damage. Alongside the laboratory biomarkers, several neuroimaging tools have shown to reflect the nature of tissue microstructural damage associated with SLE, and thus were suggested to contribute to the understanding of the pathophysiological changes and subsequently help in clinical decision making. However, the number of useful biomarkers in NP-SLE in clinical practice is disconcertingly modest. In some cases it is not clear whether the biomarker is truly involved in pathogenesis, or the result of non-specific pathophysiological changes in the nervous system (e.g., neuroinflammation) or whether it is the consequence of a concomitant underlying abnormality related to SLE activity. In order to improve the diagnosis of NP-SLE and provide a better targeted care to these patients, there is still a need to develop and validate a range of biomarkers that reliably capture the different aspects of disease heterogeneity. This article critically reviews the current state of knowledge on laboratory and neuroimaging biomarkers in NP-SLE, discusses the factors that need to be addressed to make these biomarkers suitable for clinical application, and suggests potential future research paths to address important unmet needs in the NP-SLE field.

Review: Nervous System Disease in Systemic Lupus Erythematosus: Current Status and Future Directions

The American College of Rheumatology's case definitions for 19 neuropsychiatric syndromes in systemic lupus erythematosus (SLE) constitute a comprehensive classification of nervous system events in this disease. However, additional strategies are needed to determine whether a neuropsychiatric syndrome is attributable to SLE versus a competing comorbidity. Cognitive function is a clinical surrogate of overall brain health, with applications in both diagnosis and determination of clinical outcomes. Ischemic and inflammatory mechanisms are both key components of the immunopathogenesis of neuropsychiatric SLE (NPSLE), including abnormalities of the blood-brain barrier and autoantibody-mediated production of proinflammatory cytokines. Advances in neuroimaging provide a platform to assess novel disease mechanisms in a noninvasive way. The convergence of more rigorous clinical characterization, validation of biomarkers, and brain neuroimaging provides opportunities to determine the efficacy of novel targeted therapies in the treatment of NPSLE.

Longitudinal evaluation of diffusion tensor imaging and cognition in systemic lupus erythematosus

Objective

This pilot study aimed to examine longitudinal changes in brain structure and function in patients with systemic lupus erythematosus (SLE) using diffusion tensor imaging (DTI) and neuropsychological testing.

Methods

Fifteen female SLE patients with no history of major neuropsychiatric (NP) manifestations had brain magnetic resonance imaging (MRI) with DTI at baseline and approximately 1.5 years later. At the same time points, a standardized battery of cognitive tests yielding a global cognitive impairment index (CII) was administered. At baseline, the SLE patients had mean age of 34.0 years (SD = 11.4), mean education of 14.9 years (SD = 2.1), and mean disease duration of 121.5 months (SD = 106.5). The MRI images were acquired with a 3T GE MRI scanner. A DTI sequence with 33 diffusion directions and b-value of 800 s/mm2 was used. Image acquisition time was about 10 minutes.

Results

No significant change in cognitive dysfunction (from the CII) was detected. Clinically evaluated MRI scans remained essentially unchanged, with 62% considered normal at both times, and the remainder showing white matter (WM) hyperintensities that remained stable or resolved. DTI showed decreased fractional anisotropy (FA) and increased mean diffusivity (MD) in bilateral cerebral WM and gray matter (GM) with no major change in NP status, medical symptoms, or medications over time. Lower FA was found in the following regions: left and right cerebral WM, and in GM areas including the parahippocampal gyrus, thalamus, precentral gyrus, postcentral gyrus, angular gyrus, parietal lobe, and cerebellum. Greater MD was found in the following regions: left and right cerebral WM, frontal cortex, left cerebral cortex, and the putamen.

Conclusions

This is the first longitudinal study of DTI and cognition in SLE, and results disclosed changes in both WM and GM without cognitive decline over an 18-month period. DTI abnormalities in our participants were not associated with emergent NP activity, medical decline, or medication changes, and the microstructural changes developed in the absence of macrostructural abnormalities on standard MRI. Microstructural changes may relate to ongoing inflammation, and the stability of cognitive function may be explained by medical treatment, the variability of NP progression in SLE, or the impact of cognitive reserve.

Impaired decision-making and functional neuronal network activity in systemic lupus erythematosus

Background

Systemic lupus erythematosus (SLE) is associated with cognitive deficit but the exact neural mechanisms remain unclear.

Purpose

To explore sequential brain activities using functional magnetic resonance imaging (fMRI) during the performance of a decision‐making task, and to determine whether serum or clinical markers can reflect the involvement of the brain in SLE.

Subjects

Sixteen female SLE patients without overt clinical neuropsychiatric symptoms and 16 healthy controls were included.

Field Strength/Sequence

1.5T, T₁‐weighted anatomic images, gradient‐echo echo‐planar imaging sequence, and 3D images.

Assessment

The computer‐based Iowa Gambling Task (IGT) for assessing decision‐making was performed by SLE patients and 16 matched controls; brain activity was recorded via blood oxygen level‐dependent (BOLD) fMRI. The amplitudes of the average BOLD responses were calculated for each individual subject, and activation data from fMRI experiments were compared between the two groups.

Statistical Tests

Two‐sample t‐test; repeated‐measures analysis of variance (ANOVA); linear regression analyses.

Results

Imaging revealed activity in a distributed network of brain regions in both groups, including the ventromedial prefrontal cortex (vmPFC), the orbitofrontal cortex (OFC), the dorsolateral prefrontal cortex (dlPFC), the anterior cingulate cortex (ACC), the posterior cingulate cortex (PCC), and the striatum, as well as the insular, parietal, and occipital cortices. Compared to controls, SLE patients showed lower activation in a convergence zone and the limbic system, namely, the OFC, vmPFC, ACC, and PCC, but greater activation in memory, emotion, and behavior systems involving the dlPFC, the insular cortex and the striatum. Furthermore, brain activation in the vmPFC was positively correlated with IGT scores (r = 0.63, P < 0.001), but inversely related to disease activity (r = −0.57, P < 0.01).

Data Conclusion

The dynamics among the aforementioned neural systems (some hyperfunctioning, others hypofunctioning) may shed some light on the pathologic mechanisms underlying SLE without overt clinical neuropsychiatric symptoms. In addition, disease activity may potentially be used as an effective biomarker reflecting cerebral involvement in SLE.

Level of Evidence: 1

Technical Efficacy: Stage 3

J. Magn. Reson. Imaging 2018;48:1508–1517

Advanced MRI techniques: biomarkers in neuropsychiatric lupus

Objectives

The objective of this study was to determine whether advanced MRI could provide biomarkers for diagnosis and prognosis in neuropsychiatric systemic lupus erythematosus (NPSLE).

Methods

Our prospective study included 28 systemic lupus erythematosus (SLE) patients with primary central NPSLE, 22 patients without NPSLE and 20 healthy controls. We used visual scales to evaluate atrophy and white matter hyperintensities, voxel-based morphometry and Freesurfer to measure brain volume, plus diffusion-tensor imaging (DTI) to assess white matter (WM) and gray matter (GM) damage. We compared the groups and correlated MRI abnormalities with clinical data.

Results

NPSLE patients had less GM and WM than controls ( p = 0.042) in the fronto-temporal regions and corpus callosum. They also had increased diffusivities in the temporal lobe WM ( p < 0.010) and reduced fractional anisotropy in the right frontal lobe WM ( p = 0.018). High clinical scores, longstanding disease, and low serum C3 were associated with atrophy, lower fractional anisotropy and higher diffusivity in the fronto-temporal lobes. Antimalarial treatment correlated negatively with atrophy in the frontal cortex and thalamus; it was also associated with lower diffusivity in the fronto-temporal WM clusters.

Conclusions

Atrophy and microstructural damage in fronto-temporal WM and GM in NPSLE correlate with severity, activity and the time from disease onset. Antimalarial treatment seems to give some brain-protective effects.

The diagnosis and clinical management of the neuropsychiatric manifestations of lupus

Neuropsychiatric (NP) involvement in Systemic Lupus Erythematosus (SLE), can be a severe and troubling manifestation of the disease that heavily impacts patient's health, quality of life and disease outcome. It is one of the most complex expressions of SLE which can affect central, peripheral and autonomous nervous system. Complex interrelated pathogenetic mechanisms, including genetic factors, vasculopathy, vascular occlusion, neuroendocrine-immune imbalance, tissue and neuronal damage mediated by autoantibodies, inflammatory mediators, blood brain barrier dysfunction and direct neuronal cell death can be all involved. About NPSLE a number of issues are still matter of debate: from classification and burden of NPSLE to attribution and diagnosis. The role of neuroimaging and new methods of investigation still remain pivotal and rapidly evolving as well as is the increasing knowledge in the pathogenesis. Overall, two main pathogenetic pathways have been recognized yielding different clinical phenotypes: a predominant ischemic-vascular one involving large and small blood vessels, mediated by aPL, immune complexes and leuko-agglutination which it is manifested with more frequent focal NP clinical pictures and a predominantly inflammatory-neurotoxic one mediated by complement activation, increased permeability of the BBB, intrathecal migration of autoantibodies, local production of immune complexes and pro-inflammatory cytokines and other inflammatory mediators usually appearing as diffuse NP manifestations. In the attempt to depict a journey throughout NPSLE from diagnosis to a reasoned therapeutic approach, classification, epidemiology, attribution, risk factors, diagnostic challenges, neuroimaging techniques and pathogenesis will be considered in this narrative review based on the most relevant and recent published data.

Clinical Features of Neuropsychiatric Syndromes in Systemic Lupus Erythematosus and Other Connective Tissue Diseases

Systemic lupus erythematosus (SLE) and related disorders are chronic inflammatory diseases characterized by abnormalities and, in some cases, even complete failure of immune responses as the underlying pathology. Although almost all connective tissue diseases and related disorders can be complicated by various neuropsychiatric syndromes, SLE is a typical connective tissue disease that can cause neurological and psychiatric syndromes. In this review, neuropsychiatric syndromes complicating connective tissue diseases, especially SLE are outlined, and pathological and other conditions that should be considered in the differential diagnosis are also discussed.

Altered functional neuronal activity in neuropsychiatric lupus: A systematic review of the fMRI investigations

OBJECTIVE

Recent years have seen a rapid increase in the investigation of neuropsychiatric lupus (NPSLE) through the use of functional magnetic resonance imaging (fMRI). Measuring specific neuronal activity in regional brain structures during a cognitive task may identify possible biomarker for NPSLE.

METHODS

A systematic review of fMRI studies of systemic lupus erythematosus (SLE) is carried out to address common findings that characterize NPSLE.

RESULTS

A disturbance to the working memory and executive function brain regions is among the most well-replicated finding. Differences in brain activation may relate to an early primary dysfunction of these regions. Increased functional connectivity strength in the fronto-parietal cortex in the resting state is correlated with SLE disease activity in one study. Decrease functional connectivity is observed in lupus patients with long-term disease. However, there is strong evidence that points toward a lack of effective integration of distributed functional brain regions and disruptions in the subtle modulation of brain function in relation to task demands in SLE. Limitations of the literature to date include the use of small sample size and the lack of addressing the effect of confounding variables, including immunosuppressive treatment.

CONCLUSION

Careful definitions of the fMRI technique used both in the design, analyses, and interpretation of high dimensional data is needed, when dealing with a limited number of SLE subjects with heterogeneous manifestations and unknown pathophysiology.

Advanced and Conventional Magnetic Resonance Imaging in Neuropsychiatric Lupus

Neuropsychiatric lupus is a major diagnostic challenge, and a main cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Magnetic resonance imaging (MRI) is, by far, the main tool for assessing the brain in this disease. Conventional and advanced MRI techniques are used to help establishing the diagnosis, to rule out alternative diagnoses, and recently, to monitor the evolution of the disease. This review explores the neuroimaging findings in SLE, including the recent advances in new MRI methods.

A multimodal MRI approach to identify and characterize microstructural brain changes in neuropsychiatric systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease with multi-organ involvement and results in neurological and psychiatric (NP) symptoms in up to 40% of the patients. To date, the diagnosis of neuropsychiatric systemic lupus erythematosus (NPSLE) poses a challenge due to the lack of neuroradiological gold standards. In this study, we aimed to better localize and characterize normal appearing white matter (NAWM) changes in NPSLE by combining data from two quantitative MRI techniques, diffusion tensor imaging (DTI) and magnetization transfer imaging (MTI). 9 active NPSLE patients (37 ± 13 years, all females), 9 SLE patients without NP symptoms (44 ± 11 years, all females), and 14 healthy controls (HC) (40 ± 9 years, all females) were included in the study. MTI, DTI and fluid attenuated inversion recovery (FLAIR) images were collected from all subjects on a 3 T MRI scanner. Magnetization transfer ratio (MTR), mean diffusivity (MD), fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity (AD) maps and white matter lesion maps based on the FLAIR images were created for each subject. MTR and DTI data were then co-analyzed using tract-based spatial statistics and a cumulative lesion map to exclude lesions. Significantly lower MTR and FA and significantly higher AD, RD and MD were found in NPSLE compared to HC in NAWM regions. The differences in DTI measures and in MTR, however, were only moderately co-localized. Additionally, significant differences in DTI measures, but not in MTR, were found between NPSLE and SLE patients, suggesting that the underlying microstructural changes detected by MD are linked to the onset of NPSLE. The co-analysis of the anatomical distribution of MTI and DTI measures can potentially improve the diagnosis of NPSLE and contribute to the understanding of the underlying microstructural damage.

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NAWM is investigated in NPSLE and SLE using MTI and DTI.

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Differences in DTI and MTR between NPSLE and HC are widespread but only moderately co-localized.

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Significant differences in MD between SLE and NPSLE suggest link to onset of NPSLE.

Biomarkers for childhood-onset systemic lupus erythematosus

Childhood-onset systemic lupus erythematosus (cSLE) is a systemic autoimmune disease characterized by the presence of autoantibodies. cSLE often affects multiple organs in the body and is known to have a poorer prognosis than adult-onset disease (Azevedo et al. 2014). Current laboratory tests are clearly insufficient for identifying and monitoring the disease. Recent studies have yielded novel biomarkers for cSLE which can be used for monitoring disease activity and response to treatment. The most encouraging biomarkers will be discussed herein and include cell-bound complement activation products, some genomic profiles, and urinary proteins such as neutrophil gelatinase-associated lipocalin, monocyte chemoattractant protein-1, and others. Previous studies suggested that a combination of the novel biomarkers might help to enhance sensitivity and specificity for early diagnosis, disease monitoring, and prediction of cSLE flares.

Brain abnormalities in newly diagnosed neuropsychiatric lupus: systematic MRI approach and correlation with clinical and laboratory data in a large multicenter cohort

OBJECTIVES

To describe brain magnetic resonance imaging (MRI) abnormalities in newly diagnosed neuropsychiatric lupus (NPSLE). To correlate them with clinical and laboratory data.

METHODS

This retrospective cross-sectional study included patients presenting NPSLE undergoing brain MRI within 6 months after onset between 2003 and 2012. Clinical and laboratory data were recorded. MRI findings were defined as inflammatory-like, large-vessel disease (LVD), and small-vessel disease (SVD); SVD was classified as white-matter hyperintensities (WMH), recent small subcortical infarcts, lacunes, microbleeds, and brain atrophy.

RESULTS

We included 108 patients (mean 40.6 ± 14.2 years; range 14-77), 91.7% women. The most frequent syndromes were headache (28.5%), cerebrovascular disease (15.5%), seizure (15.5%), and cognitive dysfunction (11.4%). Brain abnormalities were found in 59.3%. SVD was the most common (55.6%), followed by LVD (13%) and inflammatory-like lesions (6.5%). The most frequent SVD findings were WMH (53.7%), atrophy (18.5%), microbleeds (13.7%) and lacunes (11.1%). Cerebrovascular syndrome correlated with LVD (p = 0.001) and microbleeds (p = 0.002), cognitive dysfunction with WMH (p = 0.045) and myelopathy with inflammatory-like lesions (p = 0.020). Low C4 and CH50 correlated with inflammatory-like lesions (p < 0.001, p = 0.019) and lupus anticoagulant with WMH (p = 0.018), microbleeds (p = 0.002) and atrophy (p = 0.008).

CONCLUSIONS

Vascular disease is the hallmark of NPSLE. Certain syndromes and immunological patterns are prone to more extensive brain damage. MRI could provide significant clinical information and insights into the pathological substrate.

Reduced Insular Glutamine and N-acetylaspartate in systemic lupus erythematosus: a single-voxel (1)H-MR spectroscopy study

RATIONALE AND OBJECTIVES

To investigate for differences in metabolic concentrations and ratios between patients with systemic lupus erythematosus (SLE) without (group SLE) and those with neurological symptoms (group NPSLE) compared to a healthy control (group HC) in three normal-appearing brain regions: the frontal white matter, right insula (RI), and occipital gray matter and whether changes in any of the metabolites or metabolic ratios are correlated to disease activity and other clinical parameters.

MATERIALS AND METHODS

Twenty patients with SLE (18 women and 2 men, age range 23.4-64.6 years, mean age 43.9 years), 23 NPSLE patients (23 women, age range 23.7-69.8 years, mean age 42.4 years), and 21 HC (19 women and 2 men, age range 21.0-65.7 years, mean age 43.4 years) were included. All subjects had conventional brain magnetic resonance imaging and (1)H single-voxel spectroscopy, clinical assessment, and laboratory testing.

RESULTS

NPSLE patients had significantly reduced N-acetylaspartate (NAA)/creatine compared to HC (P = .02) and SLE patients (P = .01) in the RI. Lower glutamine/creatine levels were also detected in RI in both patient groups and in frontal white matter in NPSLE patients compared to HC (P = .01, P = .02). NAA/Cr ratio in the RI was significantly negatively correlated with the Systemic Lupus Erythematosus Disease Activity Index (r = -0.41; P = .008), and patients with active SLE symptoms also had a trend toward lower NAA/creatine ratios (1.02 vs 1.12; P = .07).

CONCLUSIONS

The present data support previous findings of abnormal metabolic changes in normal-appearing regions in the brain of both SLE and NPSLE patients and raise the possibility that especially NAA, glutamine, and glutamate may be additional biomarkers for cerebral disease activity in SLE patients as these early metabolic changes occur in the brain of SLE patients before neurologic and imaging manifestations become apparent.

Multimodal imaging in systemic lupus erythematosus patients with diffuse neuropsychiatric involvement

OBJECTIVES

The objective of this paper is to investigate conventional and nonconventional brain magnetic resonance imaging (MRI) findings in systemic lupus erythematosus (SLE) patients with diffuse neuropsychiatric involvement (dNPSLE) compared to healthy controls (HCs).

METHODS

Twenty-six (26) SLE patients with one or more diffuse NP syndromes related to the central nervous system (CNS) (dNPSLE) and 36 age- and sex-matched HCs were scanned on a 3T MRI using a multimodal imaging approach. Univariate and multivariate analyses were used to determine MRI-specific measure differences between dNPSLE and HCs for lesion burden, tissue-specific atrophy, magnetization transfer ratio (MTR) and diffusion-tensor imaging (DTI) outcomes.

RESULTS

In univariate analyses, dNPSLE patients showed significantly increased T1 lesion number (p = .001) and T1-lesion volume (LV, p = .008) compared to HCs. dNPSLE patients showed decreased whole brain volume (p < .0001), gray matter volume (p < .0001), cortical volume (p < .0001) and increased lateral ventricle volume (p = .004) compared to HCs. dNPSLE patients had increased axial diffusivity (AD) of NAWM (p = .008) and NA brain tissue (p = .017) compared to HCs. In the multivariate regression analysis, decreased cortical volume was associated with SLE (R (2) = 0.59, p < .0001).

CONCLUSIONS

This study shows that cortical and central atrophy are associated with SLE patients with diffuse CNS syndromes. Microscopic tissue injury in the NAWM on AD DTI measures in SLE patients indicates a predominant reduction of axonal density.

A multimodal evaluation of microstructural white matter damage in spinocerebellar ataxia type 3

Although white matter damage may play a major role in the pathogenesis of spinocerebellar ataxia 3 (SCA3), available data rely exclusively upon macrostructural analyses. In this setting we designed a study to investigate white matter integrity. We evaluated 38 genetically-confirmed SCA3 patients (mean age, 52.76 ± 12.70 years; 21 males) with clinical scales and brain magnetic resonance imaging (MRI) and 38 healthy subjects as a control group (mean age, 48.86 ± 12.07 years, 20 male). All individuals underwent the same protocol for high-resolution T1 and T2 images and diffusion tensor imaging acquisition (32 directions) in a 3-T scanner. We used Tract-Based Spatial Statistics (FSL 4.1.4) to analyze diffusion data and SPM8/DARTEL for voxel-based morphometry of infratentorial structures. T2-relaxometry of cerebellum was performed with in-house-developed software Aftervoxel and Interactive Volume Segmentation (IVS). Patients' mean age at onset was 40.02 ± 11.48 years and mean duration of disease was 9.3 ± 2.7 years. Mean International Cooperative Ataxia Rating Scale (ICARS) and Scale for Assessment and Rating of Ataxia (SARA) scores were 32.08 ± 4.01 and 14.65 ± 7.33, respectively. Voxel-based morphometry demonstrated a volumetric reduction of gray and white matter in cerebellum and brainstem (P <.001). We found reduced fractional anisotropy (P <.05) in the cerebellum and brainstem. There were also areas of increased radial diffusivity (P <.05) in the cerebellum, brainstem, thalamus, frontal lobes, and temporal lobes. In addition, we found decreased T2-relaxation values in the white matter of the right cerebellar hemisphere. Microstructural white matter dysfunction, not previously reported, occurs in the cerebellum and brainstem of SCA3 patients.

Repeated brain conventional MRI and SPECT evaluation in systemic lupus erythematosus patients with and without neuropsychiatric involvement: a follow up study

Objectives: To assess the utility of a combined neuroimaging approach in the follow up of patients affected by systemic lupus erythematosus (SLE) with and without neuropsychiatric (NP) involvement. Methods: Patients who underwent a first combined brain conventional magnetic resonance imaging (cMRI) and single photon emission computed tomography (SPECT) and later repeated the same examinations between 2001 and 2008 were retrieved from a large database. Clinical and neuroimaging data were analysed and their relationships evaluated at baseline and at follow up. Results: Fifty SLE patients (38 with and 12 without NP involvement, mean age 36.8 yrs and mean disease duration at first instrumental evaluation 5.5 yrs) were enrolled. At baseline, the majority of them had a diffuse pattern of NP involvement. After a mean follow up period of 4 years all patients repeated neuroimaging and clinical evaluation. In 23 patients (22 with and 1 without NP manifestations at baseline) a new NP event occurred. Overall, neuroimaging remained unchanged or improved, but in some cases it worsened. No correlations were found between instrumental findings and clinical picture. Conclusions: In this study, the clinical features at baseline appeared to be a better predictor of future NP events than morphological and functional neuroimaging. Therefore the utility of repeating a combined instrumental evaluation (cMRI and SPECT) may be debatable especially for patients with diffuse NP involvement where the decision to perform serial combined neuroimaging examinations should be carefully assessed and based mainly on clinical judgement. Lupus (2011) 20, 1387–1395.

Cognitive dysfunction and white matter abnormalities in systemic lupus erythematosus

Brain abnormalities have been documented by neuropsychological assessment as well as a variety of neuroimaging techniques in patients with systemic lupus erythematosus (SLE). Conventional neuroimaging in patients with neuropsychiatric disease (NPSLE) typically discloses periventricular white matter (WM) hyperintensities, infarcts, hemorrhages, and cerebral atrophy. In SLE patients with none of these findings, sophisticated neuroimaging techniques have recently supported associations between microstructural WM abnormalities and abnormal attention, executive function, and processing speed. This mild cognitive dysfunction in SLE (MCD-SLE), which may result from early myelinopathy, precedes the more severe cognitive dysfunction of NPSLE, related to more obvious WM and neuronal damage.

Disruption of brain white matter microstructure in primary Sjögren's syndrome: evidence from diffusion tensor imaging

OBJECTIVES

The relationship between cognitive symptoms and underlying neuropathology in primary SS (PSS) is poorly understood. We used high-resolution quantitative brain MRI to identify potential structural correlates of cognitive symptoms.

METHODS

Subjects completed a comprehensive neuropsychometric evaluation. Imaging was performed on a 3 T MRI scanner with T(1) and proton density-weighted, fluid-attenuated inversion recovery (FLAIR) and diffusion tensor imaging (DTI) sequences. We compared MRI group metrics (impaired PSS, not-impaired PSS and controls) and tested for correlations between DTI results and neuropsychological measurements (significance threshold P = 0.05).

RESULTS

Nineteen PSS patients (who met American-European Consensus Group 2002 criteria) and 17 healthy controls completed the cognitive evaluation. MRI scans were performed in six impaired PSS, seven not-impaired PSS and seven controls. No differences were found in regional volumetrics, nor was there a difference in T(2) lesion load between groups. Fractional anisotropy (FA) in the inferior frontal white matter (WM) was lower (P = 0.021) and mean diffusivity higher (P = 0.003) in the impaired PSS relative to the control group. Inferior frontal FA was correlated with cognitive symptoms (P = 0.0064) and with verbal memory (P = 0.0125).

CONCLUSIONS

In this exploratory study, frontal region WM microstructure alterations accompanied cognitive symptoms and were associated with mild cognitive impairment in PSS. While additional study is warranted to assess the specificity and stability of these results, DTI could provide novel insight into the pathological processes accompanying the subtle cognitive dysfunction commonly experienced by PSS patients.

Neurologic manifestations of systemic lupus erythematosus in children and adults

Among the collagen vascular diseases neurologic manifestations have been most commonly recognized and well-studied in systemic lupus erythematosus (SLE, lupus). Neurologic manifestations are less prevalent in other systemic inflammatory and autoimmune disorders. This review focuses on the clinical presentation, pathophysiology, and treatment strategies of neuropsychiatric lupus (NPSLE) in children and adults.

Magnetic resonance imaging and brain histopathology in neuropsychiatric systemic lupus erythematosus

OBJECTIVE

Magnetic resonance imaging (MRI) often demonstrates brain lesions in neuropsychiatric systemic lupus erythematosus (NPSLE). The present study compared postmortem histopathology with premortem MRI in NPSLE.

METHODS

Two hundred subjects with NPSLE were studied prospectively with MRI over a 10-year period during which 22 subjects died. In 14 subjects, a brain autopsy with histopathology, that permitted direct comparison with premortem MRI, was successfully obtained. Surface anatomy was used to determine the approximate location of individual lesions.

RESULTS

Premortem MRI findings in fatal NPSLE were small focal white matter lesions (100%), cortical atrophy (64%), ventricular dilation (57%), cerebral edema (50%), diffuse white matter abnormalities (43%), focal atrophy (36%), cerebral infarction (29%), acute leukoencephalopathy (25%), intracranial hemorrhage (21%), and calcifications (7%). Microscopic findings in fatal NPSLE included global ischemic changes (57%), parenchymal edema (50%), microhemorrhages (43%), glial hyperplasia (43%), diffuse neuronal/axonal loss (36%), resolved cerebral infarction (33%), microthomboemboli (29%), blood vessel remodeling (29%), acute cerebral infarction (14%), acute macrohemorrhages (14%), and resolved intracranial hemorrhages (7%). Cortical atrophy and ventricular dilation seen by MRI accurately predicted brain mass at autopsy (r = -0.72, P = 0.01, and r = -0.77, P = 0.01, respectively). Cerebral autopsy findings, including infarction, cerebral edema, intracranial hemorrhage, calcifications, cysts, and focal atrophy, were also predicted accurately by premortem MRI.

CONCLUSION

Brain lesions in NPSLE detected by MRI accurately represent serious underlying cerebrovascular and parenchymal brain injury on pathology.

Immunity and acquired alterations in cognition and emotion: lessons from SLE

Classic immunologic teaching describes the brain as an immunologically privileged site. Studies of neuroimmunology have focused for many years almost exclusively on multiple sclerosis, a disease in which inflammatory cells actually infiltrate brain tissue, and the rodent model of this disease, experimental allergic encephalitis. Over the past decade, however, increasingly, brain-reactive antibodies have been demonstrated in the serum of patients with numerous neurological diseases. The contribution these antibodies make to neuronal dysfunction has, in general, not been determined. Here, we describe recent studies showing that serum antibodies to the N-methyl-D-aspartate receptor occur frequently in patients with systemic lupus erythematosus and can cause alterations in cognition and behavior following a breach in the blood-brain barrier.

Quantifying subclinical central nervous lesions in primary antiphospholipid syndrome: the role of magnetization transfer imaging

PURPOSE

To define the role of magnetization transfer imaging (MTI) in detecting subclinical central nervous system (CNS) lesions in primary antiphospholipid syndrome (PAPS).

MATERIALS AND METHODS

Ten non-CNS PAPS patients were compared to 10 CNS PAPS patients and 10 age- and sex-matched controls. All PAPS patients met Sapporo criteria. All subjects underwent conventional MRI and complementary MTI analysis to compose histograms. CNS viability was determined according to the magnetization transfer ratio (MTR) by mean pixel intensity (MPI) and the mean peak height (MPH). Volumetric cerebral measurements were assessed by brain parenchyma factor (BPF) and total/cerebral volume.

RESULTS

MTR histograms analysis revealed that MPI was significantly different among groups (P < 0.0001). Non-CNS PAPS had a higher MPI than CNS PAPS (30.5 +/- 1.01 vs. 25.1 +/- 3.17 percent unit (pu); P < 0.05) although lower than controls (30.5 +/- 1.01 vs. 31.20 +/- 0.50 pu; P < 0.05). MPH in non-CNS PAPS (5.57 +/- 0.20% (1/pu)) was similar to controls (5.63 +/- 0.20% (1/pu), P > 0.05) and higher than CNS PAPS (4.71 +/- 0.30% (1/pu), P < 0.05). A higher peak location (PL) was also observed in the CNS PAPS group in comparison with the other groups (P < 0.0001). In addition, a lower BPF was found in non-CNS PAPS compared to controls (0.80 +/- 0.03 vs. 0.84 +/- 0.02 units; P < 0.05) but similar to CNS PAPS (0.80 +/- 0.03 vs. 0.79 +/- 0.05 units; P > 0.05).

CONCLUSION

Our findings suggest that non-CNS PAPS patients have subclinical cerebral damage. The long-termclinical relevance of MTI analysis in these patients needs to be defined by prospective studies.

Functional magnetic resonance imaging assessment of cognitive function in childhood-onset systemic lupus erythematosus: a pilot study

OBJECTIVE

To investigate changes in brain activation patterns detected by functional magnetic resonance imaging (FMRI), and the relationship between FMRI activation patterns and results of formal neuropsychological testing, in patients with childhood-onset systemic lupus erythematosus (SLE).

METHODS

Ten patients with childhood-onset SLE underwent formal neuropsychological testing and FMRI using 3 paradigms: a continuous performance task (CPT) to evaluate attention, an N-Back task to assess working memory, and verb generation to evaluate language processing. Composite Z maps were generated to summarize the brain activation patterns for each FMRI paradigm in patients with childhood-onset SLE and to compare these patterns with those observed in healthy controls. Between-group comparison Z maps showing differences in activation between childhood-onset SLE patients and controls were generated, using a significance level of P < 0.05 in a general linear model.

RESULTS

Compared with the control group, the childhood-onset SLE group showed statistically significant increased activation of brain areas involved in the CPT, N-Back, and verb generation tasks. In contrast, in the absence of active stimulus, e.g., during times of the paradigm control tasks, childhood-onset SLE patients consistently undersuppressed activity in the expected brain areas. Activation in selected cortical areas was found to correlate negatively with results of a subset of individual neuropsychological test scores.

CONCLUSION

FMRI abnormalities are present in childhood-onset SLE, manifesting as an imbalance between active and inhibitory responses to an array of stimuli. Differences in brain activation patterns compared with those observed in controls suggest that childhood-onset SLE may be associated with abnormalities in white matter connectivity resulting in neuronal network dysfunction, rather than injury of specific gray matter areas.

Assessing "occult" cervical cord damage in patients with neuropsychiatric systemic lupus erythematosus using diffusion tensor MRI

BACKGROUND

Whereas focal and diffuse brain damage on conventional MRI is seen in patients with neuropsychiatric systemic lupus erythematosus (NSLE), the spinal cord seems to be rarely involved. Diffusion tensor (DT) MRI provides information on the patterns of tissue disruption of the central nervous system, which may go undetected by conventional MRI.

OBJECTIVE

To quantify the extent of otherwise "occult" injury of the cervical cord in NSLE, and to improve our understanding of its nature.

SUBJECTS AND METHODS

Conventional and DT MRI scans of the cervical cord and brain were acquired from 11 patients with NSLE and 10 healthy controls. Histograms of mean diffusivity (MD) and fractional anisotropy (FA) of the cervical cord and brain were analysed. Measures of cervical cord and brain atrophy and focal lesion loads were computed.

RESULTS

Only one patient had a single focal lesion of the cord whereas all had multiple brain lesions on conventional MRI scans. Cord and brain volumes did not differ between patients and controls. Mean peak height of the cervical cord MD histogram (p = 0.0001) and average brain FA (p = 0.001) were significantly lower in patients than in controls. Average cord MD was correlated with average brain MD (r = 0.69, p = 0.01) and FA (r = -0.81, p = 0.002).

CONCLUSION

DT MRI shows mild and otherwise "occult" cord damage in NSLE, which might be secondary to Wallerian degeneration of long tract fibres passing trough damaged areas of the brain.

Diffusion-weighted imaging of the brain in infants and children

During the last decade, diffusion-weighted imaging (DWI) has become an important tool in the evaluation of a variety of disorders of the central nervous system in children. DWI relies on variability in the diffusivity of water molecules in the presence of a supplemental diffusion-sensitizing gradient to produce image contrast. Pathologic states alter the diffusion characteristics of brain water in a reproducible fashion. In this review, the DWI appearances of a number of common abnormalities of the brain in infants and children are presented.

Comparison of the clinical manifestations, brain MRI and prognosis between neuroBeçhet's disease and neuropsychiatric lupus

BACKGROUND

Neuropsychiatric systemic lupus erythematosus (NPSLE) shows some similarities to neuroBeçhet disease (NBD) in that both conditions have some analogous clinical features and they are both pathologically associated cerebral vasculopathy. This study compared the clinical manifestations, brain MRI findings and prognosis of NPSLE and NBD patients.

METHODS

Forty three patients with NPSLE (n = 25) or NBD (n = 18), who were monitored at a single center, were enrolled in this study. We retrospectively analyzed the clinical and brain MRI data. The neuropsychiatric manifestations were classified in both groups according to the new American College of Rheumatology nomenclature for NPSLE.

RESULTS

The diffuse symptoms that included mood disorders, psychosis, confusion, cognitive dysfunctions, generalized seizures and headaches other than migraine or cluster headaches were more commonly observed in the NPSLE patients, while the frequency of focal diseases such as cranial neuropathy tended to be higher in the NBD patients. The brain MRI revealed that the NBD patients had more abnormalities in the brain stem than did the NPSLE patients. Most of the patients improved, at least partially, after being treated with glucocorticoid and/or immune suppressants. However, the disease course differed significantly between the two groups. There were more episodic cases in the NPSLE group of patients, while there were more remittent cases in the NBD group of patients.

CONCLUSION

NPSLE had a tendency to cause diffuse neuropsychiatric manifestations, and it has a different predilection of brain lesions compared with NBD. The NBD patients showed a poorer outcome than did the NPSLE patients, suggesting that different therapeutic strategies for the two diseases need to be considered.

Central nervous system involvement in systemic connective tissue diseases

Systemic connective tissue diseases can affect the brain, meninges, spinal cord, cranial and peripheral nerves. Different pathogenic mechanisms, particularly autoantibody or T-cell mediated lesions, appear to be involved. The neurological manifestations of the connective tissue diseases and their diagnostic possibilities including newer imaging techniques are reviewed. Early recognition of neurological abnormalities can help in the differential diagnosis and in defining the underlying disease in order to initiate treatment and prevent progression of lesion or cognitive function loss.

Association between microscopic brain damage as indicated by magnetization transfer imaging and anticardiolipin antibodies in neuropsychiatric lupus

The pathogenetic role of anticardiolipin antibodies (aCLs) in patients with neuropsychiatric systemic lupus erythematosus (NPSLE) without cerebral infarcts remains elusive. Magnetization transfer imaging (MTI) has proved to be a sensitive tool for detecting diffuse microscopic brain damage in NPSLE patients. In this study we examined the correlation between grey and white matter magnetization transfer ratio (MTR) parameters and the presence of IgM and IgG aCLs and lupus anticoagulant in 18 patients with systemic lupus erythematosus and a history of NPSLE but without cerebral infarcts on conventional magnetic resonance imaging. Lower grey matter mean MTR (P < 0.05), white matter mean MTR (P < 0.05), white matter peak location (P < 0.05) and grey matter peak location (trend toward statistical significance) were observed in IgM aCL-positive patients than in IgM aCL-negative patients. No significant differences were found in MTR histogram parameters with respect to IgG aCL and lupus anticoagulant status, nor with respect to anti-dsDNA or anti-ENA (extractable nuclear antigen) status. This is the first report of an association between the presence of aCLs and cerebral damage in grey and white matter in NPSLE. Our findings suggest that aCLs are associated with diffuse brain involvement in NPSLE patients.