Discrepancy between regional cerebral blood flow and glucose metabolism of the brain in systemic lupus erythematosus patients with normal brain magnetic resonance imaging findings

18 F-FDG PET/CT Reveals Localized Inflammation in Lupus Enteritis

ABSTRACT

Lupus enteritis is classified into the colon poly-ulcerative type and the small intestine ischemic serositis type. Colon poly-ulcerative lupus enteritis is a disease that is mainly due to mesenteric arteritis. In recent years, 18 F-FDG PET/CT has been frequently used to assess the extent of the disease in patients with systemic vasculitis. We present the case report of 18 F-FDG PET/CT results in a 57-year-old woman with colon poly-ulcerative lupus enteritis.

Cognitive dysfunction in SLE: An understudied clinical manifestation

Neuropsychiatric lupus (NPSLE) is a debilitating manifestation of SLE which occurs in a majority of SLE patients and has a variety of clinical manifestations. In the central nervous system, NPSLE may result from ischemia or penetration of inflammatory mediators and neurotoxic antibodies through the blood brain barrier (BBB). Here we focus on cognitive dysfunction (CD) as an NPSLE manifestation; it is common, underdiagnosed, and without specific therapy. For a very long time, clinicians ignored cognitive dysfunction and researchers who might be interested in the question struggled to find an approach to understanding mechanisms for this manifestation. Recent years, however, propelled by a more patient-centric approach to disease, have seen remarkable progress in our understanding of CD pathogenesis. This has been enabled through the use of novel imaging modalities and numerous mouse models. Overall, these studies point to a pivotal role of an impaired BBB and microglial activation in leading to neuronal injury. These insights suggest potential therapeutic modalities and make possible clinical trials for cognitive impairment.

Different patterns of cerebral perfusion in SLE patients with and without neuropsychiatric manifestations

To investigate brain perfusion patterns in systemic lupus erythematosus (SLE) patients with and without neuropsychiatric systemic lupus erythematosus (NPSLE and non-NPSLE, respectively) and to identify biomarkers for the diagnosis of NPSLE using noninvasive three-dimensional (3D) arterial spin labeling (ASL). Thirty-one NPSLE and 24 non-NPSLE patients and 32 age- and sex-matched normal controls (NCs) were recruited. Three-dimensional ASL-MRI was applied to quantify cerebral perfusion. Whole brain, gray (GM) and white matter (WM), and voxel-based analysis (VBA) were performed to explore perfusion characteristics. Correlation analysis was performed to find the relationship between the perfusion measures, lesion volumes, and clinical variables. Receiver operating characteristic (ROC) analysis and support vector machine (SVM) classification were applied to differentiate NPSLE patients from non-NPSLE patients and healthy controls. Compared to NCs, NPSLE patients showed increased cerebral blood flow (CBF) within WM but decreased CBF within GM, while non-NPSLE patients showed increased CBF within both GM and WM. Compared to non-NPSLE patients, NPSLE patients showed significantly reduced CBF in the frontal gyrus, cerebellum, and corpus callosum. CBF within several brain regions such as cingulate and corpus callosum showed significant correlations with the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and the Systemic Lupus International Collaborating Clinics (SLICC) damage index scores. ROC analysis showed moderate performance in distinguishing NPSLE from non-NPSLE patients with AUCs > 0.7, while SVM analysis demonstrated that CBF within the corpus callosum achieved an accuracy of 83.6% in distinguishing NPSLE from non-NPSLE patients. Different brain perfusion patterns were observed between NPSLE and non-NPSLE patients. CBF measured by noninvasive 3D ASL could be a useful biomarker for the diagnosis and disease monitoring of NPSLE and non-NPSLE patients.

Cognitive Dysfunction in Systemic Lupus Erythematosus: A Case for Initiating Trials

Cognitive dysfunction (CD) is an insidious and underdiagnosed manifestation of systemic lupus erythematosus (SLE) that has a considerable impact on quality of life, which can be devastating. Given the inconsistencies in the modes of assessment and the difficulties in attribution to SLE, the reported prevalence of CD ranges from 5% to 80%. Although clinical studies of SLE-related CD have been hampered by heterogeneous subject populations and a lack of sensitive and standardized cognitive tests or other validated objective biomarkers for CD, there are, nonetheless, strong data from mouse models and from the clinical arena that show CD is related to known disease mechanisms. Several cytokines, inflammatory molecules, and antibodies have been associated with CD. Proposed mechanisms for antibody- and cytokine-mediated neuronal injury include the abrogation of blood-brain barrier integrity with direct access of soluble molecules in the circulation to the brain and ensuing neurotoxicity and microglial activation. No treatments for SLE-mediated CD exist, but potential candidates include agents that inhibit microglial activation, such as angiotensin-converting enzyme inhibitors, or that protect blood-brain barrier integrity, such as C5a receptor blockers. Structural and functional neuroimaging data have shown a range of regional abnormalities in metabolism and white matter microstructural integrity in SLE patients that correlate with CD and could in the future become diagnostic tools and outcome measures in clinical trials aimed at preserving cognitive function in SLE.

Brain Single Photon Emission Computed Tomography Scan (SPECT) and functional MRI in Systemic Lupus Erythematosus Patients with Cognitive Dysfunction: A Systematic Review

Objectives

Systemic lupus erythematosus (SLE) is an autoimmune disease with a wide range of clinical manifestations. Cognitive dysfunction is one of the manifestations that could present prior to the emergence of any other neuropsychiatric involvements in SLE. Cognitive dysfunction is a subtle condition occurring with a high frequency. However, there is no data on the correlation of cognitive dysfunction with central nervous system (CNS) imaging findings, in particular single-photon emission computed tomography scan (SPECT) and functional MRI. We decided to perform a systematic review of brain SPECT and fMRI in SLE patients with cognitive dysfunction.

Methods

PubMed, Scopus, and Google Scholar databases were searched until April 2017 with the following keywords: "SLE OR systemic lupus erythematous OR lupus" AND "functional MRI OR functional magnetic resonance imaging OR fMRI OR SPECT or SCAN". A total of 1,767articles were found. Two rheumatologists reviewed the articles and finally 14 articles were selected for the final systematic review.

Results

The fMRI and SPECT imaging techniques could provide valuable information regarding the SLE patients with cognitive dysfunction at the early stages of the disease.

Conclusion

Brain SPECT scan and fMRI are used as functional imaging tools in SLE. Both of these diagnostic modalities are sensitive in reflecting the subtle brain damages in SLE patients with cognitive dysfunction. Brain fMRI and SPECT scan could be significantly beneficial in the diagnosis and initial management of cognitive dysfunction in SLE. Nevertheless, prospective studies could be useful in confirming the application of these diagnostic modalities in the clinical setting.

Diagnostic approach to neuropsychiatric lupus erythematosus: what should we do?

Neuropsychiatric systemic lupus erythematosus is a diagnostic challenge due to the multifarious neurological and psychiatric manifestations that define it but, when suspected, diagnostic imaging can give a fundamental help. The advancements and variety of neuroimaging techniques allow us to perform more and more accurate evaluations of structure, perfusion, and metabolism of the brain and to detect cerebral and spinal lesions. Moreover, vascular districts of the neck and the brain, as well as the electrical brain and peripheral muscle activity may be accurately investigated, thus giving us a wide panoramic view. Although magnetic resonance is recognized as a fundamental neuroimaging technique to reach a correct diagnosis, the juxtaposition of other diagnostic techniques has improved the possibility to make diagnoses but has also increased the confusion about deciding which of them to use and when. Our aim was to combine the number of available techniques with the need to simplify the diagnostic path. Therefore, through the construction of an algorithm from an evidence based approach, we believe we are providing some added improvements to facilitate and expedite the diagnosis of NPSLE.

Decreased Coupling Between Functional Connectivity Density and Amplitude of Low Frequency Fluctuation in Non-Neuropsychiatric Systemic Lupus Erythematosus: a Resting-Stage Functional MRI Study

In this study, we seek to explore alterations of coupling between functional connectivity density (FCD) and amplitude of low frequency fluctuation (ALFF) in systemic lupus erythematosus patients without overt neuropsychiatric symptoms (non-NPSLE) by using resting-state functional MR imaging. This study was approved by the institutional ethical review board, and all participants signed written informed consent prior to the study. Twenty six non-NPSLE patients and 35 matched healthy controls underwent resting-state functional MR imaging. The correlation analysis between FCD and ALFF was conducted to assess the imaging coupling. Pearson correlation analysis was performed to correlate imaging variables to clinical and neuropsychological data in non-NPSLE patients. According to the consistent alteration of FCD and ALFF, region of interests were identified including the right inferior temporal gyrus, bilateral hippocampus-parahippocampus (H-PH), left posterior cingulate cortex, superior parietal gyrus, postcentral gyrus, and bilateral precuneus. Across-voxel correlation analysis showed decreased coupling strengths in some brain regions. Correlations between FCD, ALFF, and coupling strength in H-PH and C3/C4/MoCA were found. The imaging coupling between FCD and ALFF was decreased in non-NPSLE patients, indicating brain function alteration in non-NPSLE patients, especially the abnormal coupling between FCD and ALFF of the hippocampus-parahippocampus might be an imaging biomarker of brain dysfunction in non-NPSLE patients.

Evaluation of average amount of cerebral blood flow measured by brain perfusion index in patients with neuropsychiatric systemic lupus erythematosus

We used the brain perfusion index (BPI), an indicator of the average amount of cerebral blood flow (CBF), to evaluate the usefulness of the average amount of CBF for neuropsychiatric systemic lupus erythematosus (NPSLE). Of the seventy three SLE patients examined in this study (total 100 scans), 16 patients (23 scans) had already been diagnosed with NPSLE based on clinical symptoms indicative of central nervous system involvement. In addition, 12 patients (17 scans) exhibited the antiphospholipid antibody syndrome (APS). BPI is significantly influenced by age and we therefore used the BPI ratio (ratio of age predicted BPI to measured BPI value) for each assessment. The mean BPI value of 100 scans was 11.2 + 2.79, and the mean BPI ratio was 0.99 + 0.24 in all SLE patients. The mean BPI ratio among NPSLE (0.84 + 0.19) was significantly lower than that of the non-NPSLE patients (1.04 + 0.24) (P, 0.0005). However, there was no difference in the mean BPI ratio between APS patients (0.98 + 0.24) and non-APS patients (0.99 + 0.25). These results indicate that the mean CBF assessed by the BPI ratio using SPECT is of use in the evaluation of central nervous system involvement in SLE patients.

Non-invasive imaging to monitor lupus nephritis and neuropsychiatric systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect multiple different organs, including the kidneys and central nervous system (CNS). Conventional radiological examinations in SLE patients include volumetric/ anatomical computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound (US). The utility of these modalities is limited, however, due to the complexity of the disease. Furthermore, standard CT and MRI contrast agents are contraindicated in patients with renal impairment. Various radiologic methods are currently being developed to improve disease characterization in patients with SLE beyond simple anatomical endpoints. Physiological non-contrast MRI protocols have been developed to assess tissue oxygenation, glomerular filtration, renal perfusion, interstitial diffusion, and inflammation-driven fibrosis in lupus nephritis (LN) patients. For neurological symptoms, vessel size imaging (VSI, an MRI approach utilizing T2-relaxing iron oxide nanoparticles) has shown promise as a diagnostic tool. Molecular imaging probes (mostly for MRI and nuclear medicine imaging) have also been developed for diagnosing SLE with high sensitivity, and for monitoring disease activity. This paper reviews the challenges in evaluating disease activity in patients with LN and neuropsychiatric systemic lupus erythematosus (NPSLE). We describe novel MRI and positron-emission tomography (PET) molecular imaging protocols using targeted iron oxide nanoparticles and radioactive ligands, respectively, for detection of SLE-associated inflammation.

Brain metabolism and autoantibody titres predict functional impairment in systemic lupus erythematosus

Objective

We investigated whether systemic lupus erythematosus (SLE) disease duration or serology associate with abnormal regional glucose metabolism as measured with [¹⁸F]2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) and deficits on neuropsychological testing.

Methods

Subjects with SLE with stable disease activity, without brain damage or clinical symptoms of neuropsychiatric (NP) SLE, stratified by disease duration (short-term (ST)-SLE=disease ≤2 years, long-term (LT)-SLE=disease ≥10 years), underwent clinical assessments, neuropsychological testing, resting FDG-PET scan imaging and measurement of serum titres of antibody to N-methyl-d-aspartate receptor (DNRAb). FDG-PET scans were compared with age-matched and gender-matched healthy controls.

Results

Subjects with LT-SLE demonstrated hypometabolism in the prefrontal and premotor cortices that correlated with accrued SLE-related damage, but not with DNRAb titre or performance on NP testing. Independent of disease duration, subjects with SLE demonstrated hypermetabolism in the hippocampus and orbitofrontal cortex that correlated with impaired memory performance and mood alterations (depression, anxiety, fatigue). Serum DNRAb also correlated independently with impaired memory performance and increased anxiety. Together, serum DNRAb titre and regional hypermetabolism were more powerful predictors of performance than either alone.

Interpretation

The presence of serum DNRAbs can account for some aspects of brain dysfunction in patients with SLE, and the addition of regional measurements of resting brain metabolism improves the assessment and precise attribution of central nervous system manifestations related to SLE.

Regional brain metabolism in a murine systemic lupus erythematosus model

Systemic lupus erythematosus (SLE) is characterized by multiorgan inflammation, neuropsychiatric disorders (NPSLE), and anti-nuclear antibodies. We previously identified a subset of anti-DNA antibodies (DNRAb) cross-reactive with the N-methyl-D-aspartate receptor, present in 30% to 40% of patients, able to enhance excitatory post-synaptic potentials and trigger neuronal apoptosis. DNRAb+ mice exhibit memory impairment or altered fear response, depending on whether the antibody penetrates the hippocampus or amygdala. Here, we used 18F-fluorodeoxyglucose (FDG) microPET to plot changes in brain metabolism after regional blood-brain barrier (BBB) breach. In DNRAb+ mice, metabolism declined at the site of BBB breach in the first 2 weeks and increased over the next 2 weeks. In contrast, DNRAb- mice exhibited metabolic increases in these regions over the 4 weeks after the insult. Memory impairment was present in DNRAb+ animals with hippocampal BBB breach and altered fear conditioning in DNRAb+ mice with amygdala BBB breach. In DNRAb+ mice, we observed an inverse relationship between neuron number and regional metabolism, while a positive correlation was observed in DNRAb- mice. These findings suggest that local metabolic alterations in this model take place through different mechanisms with distinct time courses, with important implications for the interpretation of imaging data in SLE subjects.

Effect of autoimmune diseases on cognitive function

The location of both autoimmune processes and other causes of brain inflammation is important in determining the impact of inflammation on brain function. This chapter focuses on autoimmune and infectious diseases leading to inflammatory brain disease resulting in cognitive defects with a special focus on systemic lupus erythematosus (SLE). Collectively called neuropsychiatric SLE (NPSLE), NPSLE occurs in 20-95% of pediatric patients with SLE (pSLE). The incidence of cognitive dysfunction is difficult to ascertain in pediatric patients as few studies have been performed. Using formal neurocognitive testing of unselected pediatric SLE patients, the rate of cognitive abnormalities was approximately 50% and impairment was associated with longer disease duration in one study. A second small study showed global depression on performance and academic scores while a larger study using a neuropsychiatric inventory showed a 55% rate of dysfunction. These diverging findings may result from the lack of a standardized cognitive assessment battery. The Childhood Arthritis and Rheumatology Research Alliance (CARRA) group of pediatric rheumatologists proposed a 2 hour 40 minutes battery for assessment of cognitive testing of SLE patients from age 9 to 18 years. Further assessments using this battery should provide a better neurocognitive profile of pSLE.

Neuroimaging evidence of white matter inflammation in newly diagnosed systemic lupus erythematosus

OBJECTIVE

Central nervous system (CNS) involvement occurs frequently in systemic lupus erythematosus (SLE) and frequently results in morbidity. The primary pathophysiology of CNS involvement in SLE is thought to be inflammation secondary to autoantibody-mediated vasculitis. Neuroimaging studies have shown hypometabolism (representing impending cell failure) and atrophy (representing late-stage pathology), but not inflammation. The purpose of this study was to detect the presence and regional distribution of inflammation (hypermetabolism) and tissue failure, apoptosis, or atrophy (hypometabolism).

METHODS

Eighty-five patients with newly diagnosed SLE, who had no focal neurologic symptoms, were studied. Disease activity was quantified using the Safety of Estrogens in Lupus Erythematosus: National Assessment version of the SLE Disease Activity Index (SELENA-SLEDAI), a validated index of SLE-related disease activity. 18Fluorodeoxyglucose (FDG) positron emission tomography (PET) images of glucose uptake were analyzed by visual inspection and as group statistical parametric images, using the SELENA-SLEDAI score as the analysis regressor.

RESULTS

SELENA-SLEDAI-correlated increases in glucose uptake were found throughout the white matter, most markedly in heavily myelinated tracts. SELENA-SLEDAI-correlated decreases were found in the frontal and parietal cortex, in a pattern similar to that seen during visual inspection and presented in previous reports of hypometabolism.

CONCLUSION

The SELENA-SLEDAI-correlated increases in glucose consumption are potential evidence of inflammation, consistent with prior reports of hypermetabolism in inflammatory disorders. To our knowledge, this is the first imaging-based evidence of SLE-induced CNS inflammation in an SLE inception cohort. The dissociation among 18FDG uptake characteristics, spatial distribution, and disease activity correlation is in accordance with the notion that glucose hypermetabolism and hypometabolism reflect fundamentally different aspects of the pathophysiology of SLE with CNS involvement.

Cognitive impairment in systemic lupus erythematosus women with elevated autoantibodies and normal single photon emission computerized tomography

BACKGROUND

Systemic lupus erythematosus (SLE) is known to induce psychiatric disorders, from psychoses to maladaptive coping. Brain autoantibodies were proposed to explain SLE neuropsychiatric disorders and found to be elevated before the onset of clinical symptoms. We assessed cognition in Caucasian SLE women with elevated autoantibodies without overt neuropsychiatric syndromes, in conjunction with single photon emission computerized tomography (SPECT).

METHODS

31 women meeting SLE criteria of the American College of Rheumatology (ACR) were included. Patients who met the ACR neuropsychiatric definition were excluded. Matched controls were 23 healthy women from the Champagne-Ardenne region, France. Participants completed neuropsychological and autoantibodies measurements, and 19 completed SPECT.

RESULTS

61% (19/31) of women with SLE and 53% (9/17) of those with normal SPECT had significant global cognitive impairment defined as 4 T-scores <40 in cognitive tests, compared to 0% (0/23) of controls. SLE women also had significantly greater cognitive dysfunction (mean T-score) on the Wechsler Adult Intelligence Scale (WAIS) visual backspan, Trail Making Test A and B, WAIS Digit Symbol Substitution Test and Stroop Interference, compared to controls. Elevated antinuclear antibody correlated with impairment in the WAIS visual span, WAIS visual backspan, and cancellation task; elevated anti-double-stranded DNA antibody and anticardiolipin correlated respectively with impairment in the Trail Making Test A and WAIS auditive backspan. Two SLE women had abnormal SPECT.

CONCLUSIONS

A high prevalence of cognitive deficits was found in Caucasian SLE women compared to normal women, which included impairment in cognitive domains important for daily activities. Elevated autoantibodies tended to correlate with cognitive dysfunction.

The efficacy of brain F-fluorodeoxyglucose positron emission tomography in neuropsychiatric lupus patients with normal brain magnetic resonance imaging findings

Brain involvement in systemic lupus erythematosus (SLE) is a significant source of morbidity and mortality. Therefore, the early detection and treatment of brain involvement in SLE is of utmost importance; however, a confirmative diagnostic tool for neuropsychiatric SLE is yet to be developed. In this study, we investigated the efficacy of 18F-FDG-PET for detection of brain involvement in patients with SLE with normal magnetic resonance imaging (MRI) findings. Twenty patients with SLE, who presented with neuropsychiatric symptoms despite normal brain MRI findings and who underwent brain 18F-FDG-PET, were enrolled. The most common neuropsychiatric manifestation was headache (45%), followed by seizure (20%) and mood disorder (20%). 18F-FDG-PET revealed significant glucose metabolic abnormalities in 15 of 20 patients (75%). The temporal (55%) and the occipital (55%) lobes were the most susceptible brain regions, followed by the frontal lobe (50%). However, neuropsychiatric symptoms were not geographically correlated to 18F-FDG-PET findings. Two patients with abnormal 18F-FDG-PET findings underwent follow-up brain 18F-FDG-PET after remission, which showed complete resolution of abnormal glucose metabolism. Our data suggest that 18F-FDG-PET may be an additional diagnostic modality complementary to MRI, when MRI is unable to provide evidence of brain involvement in patients with SLE.

Neuropsychiatric systemic lupus erythematosus

Neuropsychiatric systemic lupus erythematosus (NPSLE) is the least understood, yet perhaps the most prevalent manifestation of lupus. The pathogenesis of NPSLE is multifactorial and involves various inflammatory cytokines, autoantibodies, and immune complexes resulting in vasculopathic, cytotoxic and autoantibody-mediated neuronal injury. The management of NPSLE is multimodal and has not been subjected to rigorous study. Different treatment regimens include nonsteroidal anti-inflammatory drugs, anticoagulation, and immunosuppressives such as cyclophosphamide, azathioprine, mycophenolate mofetil, and methotrexate. For refractory NPSLE, intravenous immunoglobulin (IVIG), plasmapheresis, and rituximab have been used. Adjunctive symptomatic treatment complements these therapies by targeting mood disorders, psychosis, cognitive impairment, seizures or headaches. Several new biological agents are being tested including Belimumab, a human monoclonal antibody that targets B lymphocyte stimulator. This review focuses on the pathophysiology, treatment, and new potential therapies for neuropsychiatric manifestations of systemic lupus erythematosus.

FDG PET Imaging of Large-Vessel Vasculitis

Diagnosis of vasculitis is challenging given the nonspecific manifestations of the diseases. [(18)F]Fluorodeoxyglucose (FDG) positron emission tomography (PET) has been increasingly used for vasculitis in clinic and has been shown to have a potential role in diagnosing large-vessel vasculitis such as giant cell vasculitis and Takayasu vasculitis, in monitoring treatment response, and in predicting disease progression. However, the exact clinical role of FDG PET for vasculitis has not been determined. Diagnosis of vasculitis should not be made solely based on PET. It is also worth noting that FDG PET has limited role in small-size vasculitis, although case reports have shown some success.

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.

The relationship between processing speed and working memory demand in systemic lupus erythematosus: evidence from a visual n-back task

OBJECTIVE

Working memory (WM) deficits have been reported previously in systemic lupus erythematosus (SLE), but the relationship between information processing speed (PS) and WM deficits in SLE is unknown. This study examined whether or not PS slowing could account for the WM deficits observed in SLE.

METHOD

A visual n-back task was used to measure simple and complex PS and WM in 40 SLE patients and 36 healthy controls. Simple PS was defined as reaction time (RT) to correct responses under a very low WM load condition (0-back), while complex PS was defined as RT to correct responses under moderate and high WM load conditions (1 and 2-back).

RESULTS

The results showed that SLE patients performed as well as the controls at the lower WM load conditions but had fewer correct responses than controls under the highest WM load condition (2-back). SLE patients had slower RTs than controls under all conditions, but they had relatively greater RT slowing than controls under the higher WM load conditions. Further, when RT for simple PS was subtracted from complex PS, SLE patients still showed slower complex PS for the 1- and 2-back compared with controls. Both simple and complex PS slowing were related to poorer accuracy scores on the 2-back condition, only for the SLE group.

CONCLUSIONS

The n-back task provides a sensitive measure of PS and WM. The results suggest that PS deficits alone could not account for the WM deficits in SLE. Disease duration, disease activity, and depression did not appear to account for the observed PS and WM deficits.

Multimodal neurophysiological and psychometric evaluation among patients with systemic lupus erythematosus

OBJECTIVE

To determine some of the neuropsychiatric manifestations of systemic lupus erythematosus (SLE) by applying multimodal neurophysiological and psychometric studies.

PATIENTS AND METHODS

Twenty-six SLE patients were evaluated for neurological and psychiatric disorders and compared with 26 healthy controls matched for age, sex, education, and social class. The severity of SLE disease was assessed. Each subject was subjected to the following examinations: laboratory, neurophysiology, magnetic resonance imaging of the brain, transcranial duplex, Modified Mini-mental State Examination, Cognitive Assessment Scale Inventory, Hamilton Depression Scale, and Hamilton Anxiety Scale.

RESULTS

The mean age of subjects was 25.9 ± 8.9 years. The most prevalent neurological manifestations were (in order of frequency) anxiety in 17 cases (65.4%), depression in 15 cases (57.7%), headache in 10 cases (38.5%), peripheral neuropathy in 7 cases (26.9%), seizures in 6 cases (23.1%), psychosis in 5 cases (19.2%), dementia in 4 cases (15.4%), radiculopathy in 4 cases (15.4%), myositis in 3 cases (11.5%), and stroke in 2 cases (7.7%). There was a significant affection in amplitude of the ulnar nerve, cognitive function impairment, and electroencephalography changes. There was a significant increased mean velocity and decreased Pulsatility Index of the most studied intracranial vessels in the patients.

CONCLUSION

The use of multimodal neurophysiological, transcranial duplex, and psychometric scales increases the sensitivity for detecting nervous system involvement.

Subclinical cerebrovascular cognitive function, and mood changes in patients with systemic lupus erythematosus

OBJECTIVE

To estimate the prevalence of neuropsychiatric disorders, cerebral atherosclerosis in patients with systemic lupus erythematosus (SLE) and explore the relation between transcranial duplex findings of different intracranial vessels with neuropsychiatric affect, and Systemic lupus erythematosus disease activity index (SLEDAI).

METHODS

Twenty-six consecutive SLE patients were evaluated for neurological and psychiatric disorders. Another 26 subjects matched with respect to age, sex, education, and socioeconomic status formed the control group. SLE disease activity was assessed by the SLEDAI. For each participant, a complete medical history was obtained and clinical, laboratory, and neurophysiological examinations, magnetic resonance imaging of the brain, transcranial duplex for intracranial vessels, and psychometric evaluations were performed. For the psychometric evaluation, we used the Modified Mini-mental State Examination and Cognitive Assessment Scale Inventory to assess cognitive function, and Hamilton Depression Rating Scale and Hamilton Anxiety Scale to assess symptoms of depression and anxiety.

RESULTS

Anxiety in 65.4% is the most prevalent manifestation followed by depression in 57.7%, headache in 38.5%, peripheral neuropathy in 26.9%, seizures in 23.1%, psychosis in 19.2%, radiculopathy and dementia in 15.4% for each, myositis in 11.5%, and stroke in 7.7%. There was a significant increased mean velocity and decreased pulsatility index of most studied intracranial vessels in both patient groups than in the control group. There was significant negative correlation between SLEDAI and transcranial Doppler findings in the pulsatility index of medial circumflex artery and procoagulant activity.

CONCLUSION

Neurological disorders, cognitive impairment, depression, anxiety, psychosis and cerebrovascular changes detected by transcranial Doppler ultrasound are common in SLE.

Cerebral Blood Flow in Depressed Patients with Systemic Lupus Erythematosus

Objective.

To characterize the neural circuitry involved in depression associated with systemic lupus erythematosus (SLE), we used single photon emission computed tomography (SPECT) to study regional cerebral blood flow (CBF) in patients with SLE.

Methods.

SPECT with 99mTc-ethylcysteinate dimer was performed in 30 depressed women patients with SLE, in 14 women patients with SLE and without history of neuropsychiatric disorders, and in 25 healthy women controls. Magnetic resonance imaging was done for all subjects for diagnostic purposes. Analysis of CBF patterns was performed using statistical parametric mapping. Statistical significance was taken at uncorrected p < 0.001 at cluster level.

Results.

There were no significant differences between depressed and nondepressed patients with SLE for any rheumatologic variable. In comparison to healthy controls, depressed patients with SLE had significantly reduced CBF in bilateral frontal and temporal cortex; global maximum was located in the left precentral gyrus. There were no significant CBF differences between nondepressed patients with SLE and controls. Compared to nondepressed patients with SLE, depressed patients with SLE had significantly lower CBF in 2 clusters that had their local maxima in the right precentral gyrus and in the left superior temporal gyrus. The duration of SLE correlated with decreased perfusion in the left middle and superior frontal gyrus.

Conclusion.

Depressed patients with SLE have CBF reductions in discrete temporal and frontal regions that may account for depressive symptoms.

Neuropsychological impairment in systemic lupus erythematosus: a comparison with multiple sclerosis

In this manuscript, we review literature describing the neuropsychological and brain imaging characteristics of systemic lupus erythematosus (SLE) patients. The findings are compared and contrasted with multiple sclerosis (MS) studies, revealing similarities and differences of interest to clinicians and researchers. While cognitive impairment is somewhat less common in SLE than MS, the diseases share a similar cognitive profile with deficits most prominent on tests emphasizing the speed of information processing, working memory, and visual/spatial learning, and memory. In early or more mildly affected patients, diffuse white matter damage, which may not be apparent on conventional brain imaging, plays a major role in clinical presentation and cognitive testing. The causes of white matter damage are very different, however, and in later stages of the disease MS and SLE appear to give rise to different forms of cerebral pathology. MS may be characterized by increasing brain atrophy affecting especially the cortical and deep gray matter, at least after conversion to secondary progressive course. There is less evidence for neurodegenerative changes in SLE, but patients are increasingly at risk for cerebrovascular disease. We conclude by offering some suggestions for future clinical and imaging research.

Regional cerebral blood flow between primary and concomitant fibromyalgia patients: a possible way to differentiate concomitant fibromyalgia from the primary disease

OBJECTIVES

Technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) has been used to detect abnormal regional cerebral blood flow (rCBF) in women with primary fibromyalgia (FM). The main aim of this study was to investigate the rCBF deficit in concomitant FM patients and compare it with primary FM.

METHODS

An observational study was designed to analyse the SPECT findings in 92 female patients recruited from January 2002 to January 2004. Differences in the rCBF hypoperfusive areas between 49 primary and 29 concomitant FM patients were assessed in different areas of the brain using the chi(2)-test for statistical significance.

RESULTS

Tc-99m ECD brain SPECT in 71 FM patients revealed heterogeneous rCBF in comparison to the homogeneous scan in 14 control patients. The most prominent rCBF hypoperfusive region in both primary and concomitant FM groups was the left temporoparietal area, followed by the thalamus, right temporoparietal, frontal, and basal ganglia areas. Differences in rCBF hypoperfusion in these areas for both FM groups were not significant (all p>0.5).

CONCLUSIONS

Reduced rCBF at cortical regions, in addition to previously reported areas at the thalamus and the subcortical nucleus, in FM patients was demonstrated in this study. The perfusion deficit areas were similar between primary and concomitant FM when the underlying disease activity was quiescent. The feasibility of using this neuroimaging study to differentiate FM from the primary disease, such as rheumatoid arthritis (RA)-associated depression and neuropsychiatric lupus, should be considered.

Evaluation of cerebral perfusion in patients with neuropsychiatric systemic lupus erythematosus using 123I-IMP SPECT

OBJECTIVE

In the course of systemic lupus erythematosus (SLE), central nervous system (CNS) complications occur at a high frequency. An accurate diagnosis of CNS lupus, differentiated from secondary CNS involvement, is difficult. CNS lupus is indicative of advancing primary disease and is treated by steroid pulse therapy or increased dosage of steroids. In contrast, if symptoms are caused by secondary CNS complications, it is possible to observe or treat these complications using symptomatic therapy. We examined whether quantitative cerebral blood flow (CBF) measured using cerebral perfusion single photon emission computed tomography (SPECT) can be used to differentiate CNS lupus from secondary CNS involvement.

METHODS

We divided 18 SLE patients with CNS symptoms into a CNS lupus group and a non-CNS lupus group, and then compared the mean cerebral blood flow (mCBF) of each group of patients. SPECT was performed with N-isopropyl-p-[123I] iodoamphetamine (IMP), with quantitation carried out by table look-up and autoradiographic methods.

RESULTS

The mCBF of both groups was decreased; however, the mCBF of patients with CNS lupus was significantly lower than that of non-CNS lupus patients.

CONCLUSION

Quantitative CBF may provide a useful tool to distinguish CNS lupus from non-CNS lupus.

C-reactive protein and cognitive deficits in systemic lupus erythematosus

OBJECTIVE

Recent studies have highlighted the role of serum C-reactive protein (CRP) as a marker for atherosclerosis, and a predictor for vascular disease and stroke. Systemic lupus erythematosus (SLE) has been associated with (1) higher levels of CRP, (2) cerebrovascular disease, and (3) a "subcortical" pattern of cognitive deficits (eg, lower processing speed, poor working memory). These findings suggest that microvascular changes affect cognition in SLE. To our knowledge, no studies have yet attempted to relate levels of CRP with cognitive deficits in SLE. In the present study, we investigated the relationship between CRP level and measures of working memory/processing speed in SLE.

METHODS

The Paced Auditory Serial Addition Test (PASAT), a sensitive measure of processing speed and working memory, was administered as part of a full neuropsychologic battery. CRP levels were obtained from blood collected on the day of cognitive testing. SLE patients were divided into 2 groups: No detectable CRP (No-CRP) and detectable CRP levels (Elevated-CRP).

RESULTS

In comparison to the No-CRP group, the Elevated-CRP group performed more poorly on the PASAT. They had fewer correct responses, fewer consecutive correct responses (dyads), and a greater percentage of responses that were obtained by using a less demanding but incorrect "chunking" strategy to perform the PASAT.

CONCLUSIONS

Results suggest that CRP may be a sensitive marker for subtle executive dysfunction in SLE, possibly due to central nervous system microvascular autoimmune processes. Early treatment of vasculopathy in SLE may help prevent microvascular disease and associated cognitive dysfunction.

Cognitive dysfunction and emotional–behavioural changes in MS: The potential of positron emission tomography

Cognitive dysfunction and emotional-behavioral changes are symptoms with increasing clinical relevance during progression of the disease. They cannot be explained by demyelination of white matter alone but clearly indicate cortical dysfunction. Positron emission tomography (PET) provides methods to assess cortical dysfunction quantitatively by measuring cerebral glucose metabolism using the tracer (18)F-2-fluoro-2-deoxy-d-glucose (FDG). The technique has been employed to study fatigue and disease progression. Microglial activation was studied by 11C-PK-11195 PET. It was found not only in active plaques but also in degenerating fibre tracks. Other tracers offer a broad spectrum of measuring local physiological functions and pathophysiological processes, but some of them are still limited to experimental animal research.

Imaging in CNS lupus

The diagnosis of neuropsychiatric systemic lupus erythematosus (NPSLE) is complex not only on account of the heterogeneous nature of neurological presentation but also because of the difficulty of differentiating lupus-related pathology from other neuropsychiatric diseases. Magnetic resonance imaging (MRI) remains the gold standard for the non-invasive assessment of NPSLE but there are problems, both with sensitivity and specificity. Both T(2) quantitation and the use of gadolinium have shown promise in differentiating acute from chronic lesions. Nonetheless, the lack of sensitivity of conventional MRI has led to the exploration of other MR-based techniques. Magnetic resonance spectroscopy (MRS) allows the measurement of brain metabolites, whereas diffusion weighted imaging and diffusion tensor imaging allow assessment of white matter structure and integrity. MRS studies in NPSLE have consistently shown a reduction in N-acetyl aspartate (a neuronal marker). Diffusion weighted imaging has had only limited application in lupus and the results to date have shown abnormal diffusivity in lupus patients consistent with inflammation and loss of white matter structure. These techniques remain research tools at this early stage. Positron emission tomography (PET) and single photon emission computed tomography (SPECT) have also been explored as functional imaging tools in lupus and both appear to be more sensitive in detecting subtle brain changes in NPSLE but there are issues with specificity which deter their use in the clinical setting.

Accuracy of anti–ribosomal P protein antibody testing for the diagnosis of neuropsychiatric systemic lupus erythematosus: An international meta-analysis

OBJECTIVE

To quantitatively evaluate the diagnostic accuracy of antibodies to ribosomal P proteins (anti-P) for neuropsychiatric systemic lupus erythematosus (NPSLE) in general, for psychosis, mood disorder, or both, and for other diffuse manifestations.

METHODS

This international meta-analysis combined standardized data from 1,537 lupus patients contributed by 14 research teams. Weighted estimation of sensitivity and specificity with fixed-effects and random-effects models, as well as summary receiver operating characteristic (SROC) curve analysis, was used to summarize test performance. The robustness of the overall estimates was examined in sensitivity analyses that included additional studies published up to November 1, 2004 in the Medline, EMBase, and Cochrane databases.

RESULTS

Combining the data from the 14 teams, the weighted sensitivity and specificity estimates for the diagnosis of NPSLE were 26% (95% confidence interval [95% CI] 15-42%) and 80% (95% CI 74-85%), respectively. For psychosis, mood disorder, or both, the sensitivity and specificity were 27% (95% CI 14-47%) and 80% (95% CI 74-85%), respectively. For other diffuse manifestations, the sensitivity was 24% (95% CI 12-42%), and the specificity was 80% (95% CI 73-85%). The proportion of patients with anti-P antibodies did not vary markedly across different presentations of NPSLE. Between-study heterogeneity was substantial, but the SROC curves were consistent with the weighted estimates. In further analyses that included another 24 published studies, only the sensitivity for psychosis and/or mood disorder was slightly improved, but it was still suboptimal (42% [95% CI 30-53%]); the specificity remained essentially the same (81% [95% CI 76-85%]).

CONCLUSION

Anti-P antibody testing has limited diagnostic value for NPSLE, and it is not helpful in differentiating among various disease phenotypes.

Fatigue in patients with lupus is not associated with disturbances in cerebral blood flow as detected by SPECT

OBJECTIVES

Fatigue is a common complaint in patients with systemic lupus erythematosus (SLE). We investigated whether focal or general disturbances of cerebral blood flow (CBF), as assessed by SPECT, were associated with the presence of fatigue in an unselected group of SLE patients.

METHODS

Fifty-six patients were included. Mean age was 47.5 years (+/-12.7), mean disease duration 14.7 years (+/-8.9), and disease activity measured by SLE disease activity index (SLEDAI) was 5.7 (+/-5.4). Fatigue was assessed by the Fatigue Severity Scale (FSS) and CBF by Tc-99m-hexamethyl propylamine oxime (HMPAO)-SPECT. The images were read and processed quantitatively by a computer program using the primary visual cortex as reference region and > 15% CBF deviation as definition of abnormality.

RESULTS

The mean FSS score was 4.6 (+/-1.8). SPECT revealed focal CBF disturbances in 17 patients (30.4 %). Generalized symmetrical CBF reductions were present in 32 patients (57.1 %). There were no significant associations between CBF disturbances in any region of the brain and the degree of fatigue.

CONCLUSIONS

Fatigue in SLE patients is not related to focal or general CBF disturbances. Therefore, factors that do not influence blood flow seem responsible for the fatigue phenomenon.

Cerebral hypoperfusion detected by SPECT in patients with systemic lupus erythematosus is related to clinical activity and cumulative tissue damage

Cerebral single-photon emission computed tomography (SPECT) is a sensitive technique for the detection of central nervous system (CNS) involvement in systemic lupus erythematosus (SLE). The objective was to determine whether a relationship exists between cerebral hypoperfusion as detected by cerebral SPECT, cumulative tissue damage and the clinical activity of SLE. Cerebral technetium-99m-L,L-ethyl cysteinate dimer (99mTc-ECD) SPECT was performed in two groups of patients: 10 women with SLE (Group A) who had no previous history of major neuropsychiatric (NPS) manifestations and no minor NPS symptoms in the last six months, and 57 unselected women with SLE (Group B). In the same week that SPECT was performed, the SLE disease activity index (SLEDAI), SLICC/ACR damage index, native anti-DNA antibodies (ELISA) and erythrocyte sedimentation rate (ESR) were determined. In Group A, cerebral SPECT showed moderate or severe hypoperfusion (abnormal SPECT) in five patients without NPS symptoms, unrelated to age (mean 24.8 versus 27.8 years) or disease duration (mean 6.8 versus 9 years). Patients with significant cerebral hypoperfusion had greater clinical disease activity (mean SLEDAI 13.6 versus 7.6) (SLEDAI > 7 in 5/5 versus 1/5; Fisher: 0.023; OR: 33; 95% CI: 2.3-469.8) and ESR (mean 43.6 versus 9.8; P < 0.05). In Group B, the mean age of the 57 unselected women with SLE was 37 years (SD 6.3) and the mean duration of the disease was 9.7 years (SD 6.3). Cerebral SPECT revealed normal perfusion or mild hypoperfusion (normal SPECT) in 30 patients (52.6%), and moderate or severe hypoperfusion in 27 (47.4%). Hypoperfusion was unrelated to age, duration of SLE or concentrations of anti-DNA antibodies and C3 and C4 fractions. Patients with significant cerebral hypoperfusion had more active clinical disease (mean SLEDAI 13.92; SD 8.44 versus 4.56; SD 4.15) (Mann-Whitney, P < 0.005), more cumulative tissue damage (mean SLICC 2.66; SD 2.84 versus 1.03; SD 1.51) (Mann-Whitney, P = 0.035), and higher ESR values (mean 28.7; SD 22.5 versus 17.7; SD 13.3) (Mann-Whitney, P = 0.023) than patients with normal SPECT studies. Significant cerebral hypoperfusion was related both to NPS manifestations present at the time of the study (17 of 27, 63% versus 3 of 30, 10%) (OR: 15.3) and cumulative manifestations (19 of 27, 70.4% versus 8 of 30, 26.7%) (OR: 6.5), whether mild (OR: 5.5) or severe (OR: 8.2). In conclusion, cerebral hypoperfusion detected by SPECT in patients with SLE is related to clinical activity (SLEDAI), cumulative tissue damage (SLICC) and concomitant or previous NPS manifestations.

In vivo proton magnetic resonance spectroscopy (MRS) and single photon emission computerized tomography (SPECT) in systemic lupus erythematosus (SLE)

Neuropsychiatric involvement in SLE (NP-SLE) may not be picked up by routine neuroimaging procedures like computerized tomography (CT) or magnetic resonance imaging (MRI). We prospectively studied the role of single photon emission computerized tomography (SPECT) and magnetic resonance spectroscopy (MRS) in detection of NP-SLE in 20 patients with lupus (10 with clinical NP involvement and 10 without) and 9 healthy controls. MRI abnormalities were seen in 5/10 patients with NP-SLE while the MRI was normal in all the lupus patients without clinical NP involvement. Perfusion defects on SPECT were seen in as many as 8/10 patients with NP-SLE while only 1/10 lupus patients without clinical NP involvement and none of the healthy controls demonstrated perfusion defects. MRS revealed abnormal metabolite ratios in all patients with NP-SLE and as many as 8 lupus patients without clinical NP features. Normal metabolite ratios were observed in healthy controls. SPECT and MRS can help detect changes not evident on MRI and may serve as useful supplements to existing neuroimaging techniques in the diagnosis of NP-SLE. The precise significance of alterations in regional cerebral blood flow on SPECT and neurometabolite ratios on MRS needs larger, longitudinal studies.

Cognitive dysfunction and antiphospholipid antibodies in systemic lupus erythematosus

Nervous system involvement in systemic lupus erythematosus (SLE) is typically diagnosed on the basis of clinical psychiatric and/or neurologic syndromes (NPSLE). Neuropsychological tests can be used to assess nervous system integrity even in the absence of major NP syndromes. Their application has uncovered significant cognitive dysfunction, ranging from mild to severe, in a sizeable proportion of SLE patients irrespective of clinical NP status. Cognitive dysfunction has now been accepted as a bona fide manifestation of NPSLE. The heterogeneity of clinical NPSLE manifestations is paralleled by the diversity of cognitive deficits reported in different studies and within different patients. The success of attempts to explain these deficits on the basis of potential pathogenetic mechanisms, such as antibrain antibodies and proinflammatory cytokines, has been uneven. To date, the most robust findings have emerged in relation to antiphospholipid antibodies, which carry with them important therapeutic implications.

Using 99mTc HMPAO brain SPECT to evaluate the effects of anticoagulant therapy on regional cerebral blood flow in primary antiphospholipid antibody syndrome patients with brain involvement-a preliminary report

Technetium-99m hexamethylpropylene amine oxime ((99m)Tc HMPAO) brain single photon emission computed tomography (SPECT) was used to evaluate the effects of anticoagulant therapy (ACT) on regional cerebral blood flow (rCBF) in patients with primary antiphospholipid antibody syndrome (PAPS). Sixteen female PAPS patients with neuropsychiatric manifestations and hypoperfusion lesions demonstrated on initial (99m)Tc HMPAO brain SPECT images were enrolled in this study. Follow-up (99m)Tc HMPAO brain SPECT images were performed 1 month after ACT. Meanwhile, serum anticardiolipin antibodies (ACA) were measured before and after ACT. Before ACT, 14 (87.5%) patients had positive ACA. After ACT, all 16 PAPS patients showed decreased serologic findings, and their neuropsychiatric manifestations subsided. After ACT, 11 (68.8%) patients showed complete recovery of regional cerebral blood flow (rCBF) and five (31.2%) patients showed partial recovery in the follow-up (99m)Tc HMPAO brain SPECT images. This type of imaging is a logical and objective tool for measuring the effects of ACT in PAPS patients with brain involvement by determining changes in rCBF.

Abnormal regional cerebral blood flow on 99mTc ECD brain SPECT in patients with primary Sjögren's syndrome and normal findings on brain magnetic resonance imaging

OBJECTIVE

Technetium-99m ethyl cysteinate dimer (99mTc ECD) single photon emission computed tomography (SPECT) of the brain was used to detect abnormal regional cerebral blood flow (rCBF) in patients with primary Sjögren's syndrome (pSS) and normal findings on brain magnetic resonance imaging (MRI).

METHODS

(99m)Tc ECD brain SPECT was performed to detect brain lesions showing hypoperfusion in 32 female patients with pSS and definite neuropsychiatric symptoms or signs. Seventeen female patients with pSS without neuropsychiatric symptoms and signs were included as a control group for comparison. All of the 49 patients with pSS had normal findings on brain MRI.

RESULTS

99mTc ECD brain SPECT showed brain regions with hypoperfusion in 18 (56.3%) of the 32 patients, and parietal lobes were the most common areas with such lesions. By contrast, 99mTc ECD brain SPECT showed brain regions with hypoperfusion in only three (17.6%) of the 17 patients with pSS without neuropsychiatric symptoms or signs.

CONCLUSION

This study suggests that 99mTc ECD SPECT is a sensitive tool for detecting regions of hypoperfusion in the brains of patients with pSS and neuropsychiatric symptoms or signs and normal findings on brain MRI. However, a review of the literature showed that the (99m)Tc ECD SPECT findings in patients with pSS were non-specific.

Abnormal regional cerebral blood flow in primary antiphospholipid antibody syndrome patients with normal magnetic resonance imaging findings. A preliminary report

Technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) was used to detect abnormal regional cerebral blood flow (rCBF) in primary antiphospholipid antibody syndrome (PAPS) patients. The patients had mild neuropsychiatric manifestations and normal brain magnetic resonance imaging (MRI) findings in this preliminary study. Fifteen such female PAPS patients were examined with Tc-99m ECD brain SPECT in order to evaluate the rCBF. In addition, serum anti-cardiolipin antibodies (ACA) and lupus anticoagulant (LA) were simultaneously measured for comparison.

RESULTS

(a) Tc-99m ECD brain SPECT revealed hypoperfusion brain lesions in 12 (80%) of the PAPS patients. Pariental lobes were the most commonly involved areas. (b) 11 (73%) and 9 (60%) cases had positive ACA and positive LA, respectively. In addition, ACA and LA results were correlated to the Tc-99m ECD brain SPECT findings. Tc-99m ECD brain SPECT is a sensitive tool for detecting abnormal rCBF in PAPS patients with mild neuropsychiatric manifestations and normal brain MRI findings.

Diagnosis and management of patients with neuropsychiatric systemic lupus erythematosus (NPSLE)

Neuropsychiatric systemic lupus erythematosus (NPSLE) involves a wide range of focal and diffuse central and peripheral nervous system disorders and affects up to 75% of SLE patients. NPSLE can occur any time in the course of SLE, even during periods in which no SLE disease activity is detected, and is likely to be caused by multiple factors, including autoantibody production, microvasculopathy and pro-inflammatory cytokines. Central to the diagnosis of NPSLE is the question of whether the presenting neuropsychiatric symptoms are due to SLE-mediated organ dysfunction, infection, medication side-effects or metabolic abnormalities (e.g. uraemia), or are due to an unrelated condition. The diagnostic inference of NPSLE can be made only after these secondary causes have been excluded. There is no one single diagnostic tool specific to NPSLE, and clinical diagnostic impressions must be based on the combined use of immunoserological testing, functional and/or structural neuroimaging and standardized neurological, rheumatological, psychiatric and neuropsychological assessments. The management of NPSLE includes symptomatic and/or immunosuppressive treatment strategies depending on the specific presenting neuropsychiatric symptoms and whether these occur in the setting of an SLE disease activity flare.

Neuropsychiatric lupus

Neuropsychiatric (NP) manifestations of systemic lupus erythematosus (SLE) have been recognized for more than 100 years but continue to pose a diagnostic and therapeutic challenge for rheumatologists and other physicians involved in the care of SLE patients. NP-SLE includes a plethora of clinical manifestations and the reported prevalence has varied widely between 14% and 75%. The recent introduction of a standard nomenclature, case definitions, and diagnostic criteria for 19 NP-SLE syndromes should facilitate a more consistent approach to the classification of patients and to the execution of large multicenter clinical studies. The etiology of NP-SLE is likely multifactorial and includes microangiopathy, autoantibody production, and the intrathecal production of proinflammatory cytokines. Newer imaging modalities of brain structure and function provide novel ways of understanding pathogenic mechanisms. The use of standardized neuropsychometric techniques to evaluate cognitive function has identified a high prevalence of cognitive impairment in SLE patients. The management of patients with NP-SLE includes symptomatic and immunosuppressive therapies, evidence for which is largely limited to uncontrolled clinical trials and anecdotal experience. Multicenter initiatives are required to address important issues on prognosis and management.

Cerebral perfusion in patients with syndrome X: a single photon emission computed tomography study

OBJECTIVE

To test the hypothesis that syndrome X is a systemic vascular disorder, the authors studied 40 patients with this diagnosis using technetium-99m hexamethylpropylene amine oxime and single photon emission computed tomography (SPECT) brain images. Twenty-three of 25 cases with definite myocardial perfusion defects diagnosed by thallium-201 myocardial perfusion SPECT also had multiple hypoperfusion areas in the brain versus 2 of 15 patients without thallium myocardial defects. The parietal lobes were the most common hypoperfusion areas, and cerebellum was the least common. Syndrome X is a systemic vascular disorder with a high incidence of hypoperfusion lesions of the brain and is usually coincident with myocardial defects.

Prevalence and pattern of cognitive impairment in systemic lupus erythematosus patients with and without overt neuropsychiatric manifestations

The prevalence and pattern of cognitive impairment in systemic lupus erythematosus (SLE) patients with (NPSLE) and without (nSLE) overt neuropsychiatric manifestations were investigated. Fifty-two nSLE patients, 23 NPSLE patients and 27 healthy controls were evaluated with a battery of standardized neuropsychological and psychological tests. Disease duration, disease activity index, and current corticosteroid therapy were collected. Cognitive impairment was identified in 14 (26.9%) and in 12 (52.2%) of subjects with nSLE and NPSLE, respectively. Both SLE groups showed a significant impairment compared with controls on tasks assessing verbal and non-verbal long-term memory, and visuoconstructional abilities. In addition, NPSLE patients reported worse performances than both nSLE patients and controls on task evaluating short-term visuospatial memory. NPSLE subjects were significantly more anxious and depressed compared to both nSLE subjects and controls. By multivariate analysis, only depression levels, among clinical variables, significantly predicted cognitive performance. This study shows that cognitive impairment occurs frequently in both nSLE and NPSLE subjects. The higher frequency in NPSLE may be related to coexisting depressive disturbances.

Alterations of cerebral glucose metabolism indicate progress to severe morphological brain lesions in neuropsychiatric systemic lupus erythematosus

Neuropsychiatric systemic lupus erythematosus (SLE) is frequently associated with deficits in brain glucose metabolism, even if morphological imaging by magnetic resonance imaging (MRI) shows no abnormalities. In these patients it is unclear whether or not the changes of brain metabolism measured by F-18-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) may progress to lesions of cerebral structure. We describe a 20-year-old woman with SLE who presented with depression, headache and impairment of memory. Initially, a cranial MRI was negative, but FDG-PET revealed significant hypometabolism in the frontal and parieto-temporo-occipital regions on both sides as well as hypermetabolism in the nuclei caudati. Within two months the patient developed an acute confusional state, seizures, visual disturbances and cranial MRI became positive showing hyperintensities at the basal ganglia and the temporo-occipital regions. Focal cerebral symptoms responded to treatment with high dose corticosteroids and brain lesions in MRI disappeared. However, a second FDG-PET showed persistent hypometabolism at frontal regions in accordance with the persistence of subclinical depression. To our knowledge, this is the first SLE case report showing that functional brain lesions visualized by FDG-PET may be a risk factor for subsequent structural brain damage seen in MRI. Thus, FDG-PET may help to verify cerebral involvement of SLE earlier than MRI.

Cerebral blood flow and glucose metabolism in multi-infarct-dementia related to primary antiphospholipid antibody syndrome

The primary antiphospholipid antibody syndrome (PAPS) has been described in patients with a history of fetal loss, thrombocytopenia and arterial or venous thrombosis. In PAPS, a prothrombotic state is mediated by antiphospholipid antibodies (aPLs) leading to disseminated thromboembolic vascular occlusion. Today, the presence of aPLs in the serum is considered as a distinct risk factor for recurrent stroke in young adults. Some PAPS patients develop a multi-infarct-syndrome with a stepwise decline of higher cortical functions. We report on a 55-year-old man suffering from progressive dementia and PAPS, in whom cerebral glucose metabolism and blood flow were examined by positron emission tomography (PET). Cerebral atrophy and moderate signs of leukaraiosis were detected in magnetic resonance imaging (MRI), whereas the PET scans showed a considerable diffuse impairment of cortical glucose metabolism combined with a reduced cerebral perfusion in the arterial border zones. These findings indicate that PAPS-associated vascular dementia is accompanied by a cortical neuronal loss, presumably caused by a small-vessel disease with immune-mediated intravascular thrombosis. This case shows that pathological findings in PAPS are congruent to cerebral changes of metabolism and blood flow in systemic lupus erythematosus (SLE).

Diagnosis and monitoring of central nervous system involvement in systemic lupus erythematosus: value of F-18 fluorodeoxyglucose PET

OBJECTIVE

To investigate prospectively abnormalities of brain glucose utilisation in relation to major or minor neuropsychiatric symptoms in systemic lupus erythematosus (SLE).

METHODS

Positron emission tomography (PET) using F-18-labelled fluorodeoxyglucose was performed in 28 patients with SLE. Patients were classified as having severe neuropsychiatric manifestations (seizures, focal neurological deficits, acute confusional states, mood disorders) (n=12), or mild neuropsychiatric manifestations (headache, reactive depression, cognitive dysfunction, anxiety disorders) (n=11) and five patients without signs of central nervous system (CNS) involvement. Ten clinically and neurologically healthy volunteers served as controls. In 26 patients magnetic resonance imaging (MRI) was performed and autoantibodies against CNS tissue, ribosomal P protein and cardiolipin were measured. In 14 patients follow up PET scans were performed after a mean (SD) period of 11.6 (9.5) months.

RESULTS

PET scans showed hypometabolism in at least one brain region in all patients with severe or mild CNS symptoms (100%) as compared with patients without cerebral symptoms (40%) (p<0.0025). Parieto-occipital regions were most commonly affected (96%), followed by parietal regions (32%). In contrast, MRI images were abnormal in only 11 of 22 patients (50%) with neuropsychiatric symptoms and in one of four patients (25%) without symptoms. In 12 of 14 patients examined in follow up PET scans persistence, improvement or worsening of cerebral symptoms were associated with unchanged, decreased or increased brain hypometabolism, respectively. No significant correlation was found between PET or MRI findings and autoantibody profiles.

CONCLUSIONS

PET imaging represents a sensitive tool to detect manifest or subclinical CNS involvement in SLE and PET findings correlate well with the clinical course of disease.

Systemic lupus erythematosus and related disorders of childhood

Systemic lupus erythematosus (SLE) remains a challenging autoimmune disease in term of its etiology, pathogenesis, and management. Much progress has been made in the past year in searching for the SLE susceptibility genes, particularly by several genome-wide screening groups. Cumulative evidence about the association of infections and hormones with SLE has been gathered. Researchers believe that childhood SLE involves more severe organ involvement than adult SLE. Central nervous system complicated lupus continues to be problematic because functional imaging can be abnormal in otherwise asymptomatic lupus individuals. Whether these abnormalities result from subclinical central nervous system involvement or from false positives remains to be determined. With the wide use of corticosteroids as a cornerstone therapy for major organ involvement in childhood SLE, potential complications, especially those involving the growing bone or osteoporosis, are a cause of concern. Evidence suggests that regular exercise, as well as calcium and vitamin D supplementation, may help alleviate bone complications. Researchers have also updated information about pediatric antiphospholipid antibody syndrome. Follow-up studies on neonatal lupus and its pathogenesis have progressed, leading to a better understanding of its natural history and, in turn, to proper counseling of mothers of infants with neonatal lupus and of women with positive anti-Ro or anti-La antibodies. Drug-induced lupus in children is not uncommon. Minocycline and zafirlukast have been increasingly used, and were reported to induce lupus in children.