Gerda M. Steup-Beekman

Neuropsychiatric systemic lupus erythematosus: lessons learned from magnetic resonance imaging

OBJECTIVE The clinical manifestations of nervous system involvement in systemic lupus erythematosus (neuropsychiatric SLE [NPSLE]) are highly diverse, and their etiology is incompletely understood. The aim of this study was to provide an inventory of abnormalities on conventional brain magnetic resonance imaging (MRI) in NPSLE and to interpret the findings in relation to possible underlying pathogenetic mechanisms. METHODS MR images of the first episode of active NPSLE in 74 patients were retrospectively reviewed. All patients fulfilled the American College of Rheumatology (ACR) 1982 revised criteria for the classification of SLE and were classified according to the 1999 ACR case definitions for NPSLE syndromes. We excluded patients with a history of brain disease and patients in whom other mechanisms unrelated to SLE caused the neuropsychiatric symptoms. RESULTS The principal findings were: 1) focal hyperintensities in white matter (WM) (49% of all patients) or both WM and gray matter (GM) (5% of all patients), suggestive of vasculopathy or vasculitis; 2) more widespread, confluent hyperintensities in the WM, suggestive of chronic hypoperfusion due to the same mechanisms; 3) diffuse cortical GM lesions (12% of all patients), compatible with an immune response to neuronal components or postseizure changes; and 4) absence of MRI abnormalities, despite signs and symptoms of active disease (42% of all patients). CONCLUSION Several distinct brain MRI patterns were observed in patients with active NPSLE, suggestive of different pathogenetic mechanisms. To advance our understanding of the various processes leading to NPSLE, the radiographic manifestations may be a good starting point and useful for categorization of patients in further research.

Diagnosis and management of the antiphospholipid syndrome.

#### Summary points Antiphospholipid syndrome was first described 27 years ago in patients with systemic lupus erythematosus (SLE) and positive anticardiolipin antibodies, who presented with a clotting syndrome that affected arteries and veins.1 Female patients had a high risk of recurrent miscarriage and late fetal loss. The international classification criteria for this syndrome used today are based on those initial clinical observations.2 The syndrome is under-recognised and underdiagnosed and can have devastating consequences if untreated, mainly because of uncontrolled thrombosis. Difficulties in diagnosis are compounded by a lack of standardisation of diagnostic tests. Early recognition is crucial, because treatment can reduce mortality and morbidity in relatively young people who often present with diseases such as stroke, myocardial infarction, and deep vein thrombosis. Because of its variable clinical presentation, patients with antiphospholipid syndrome present to a variety of medical practitioners. Here, we introduce this complicated and intriguing syndrome, and provide basic guiding principles for the recognition, diagnosis, and management of affected patients. #### Sources and selection criteria We searched the following databases for evidence from systematic reviews, clinical trials, and prospective cohort studies: PubMed (1949 to January 2010), Embase (1980 to January 2010), Web of Science (1945 to January 2010), Cochrane Library (1990 to January 2010), CINAHL (1982 to January 2010), and Academic Search Premier (1865 to January 2010). All relevant keyword variations were used. In general, the …

Potential for glomerular C4d as an indicator of thrombotic microangiopathy in lupus nephritis.

OBJECTIVE In patients with systemic lupus erythematosus (SLE) and lupus nephritis, the presence of antiphospholipid antibodies (aPL) is considered to be an indication of increased risk of thrombotic microangiopathy, a serious complication of SLE. Previous studies have demonstrated a critical role for activation of the classical pathway of complement that leads to thrombotic injury in the presence of aPL. This study was undertaken to investigate whether C4d deposition in lupus nephritis is related to circulating aPL and the presence of renal microthrombi. METHODS Deposition patterns of C4d in 44 renal biopsy samples obtained from 38 patients with biopsy-proven lupus nephritis were determined by staining with a polyclonal anti-C4d antibody. A phosphotungstic acid-hematoxylin stain was used to identify fibrin microthrombi. Clinical data (serum creatinine levels and presence or absence of aPL) were obtained and correlated with findings in the renal biopsy specimens. Patients were categorized as having aPL (n = 20) or not having aPL (n = 18). RESULTS A strong relationship between the intensity of glomerular C4d staining and the presence of microthrombi was found (P < 0.002). Intense glomerular C4d deposition was present in 7 of 8 biopsy samples showing renal microthrombi. Neither C4d deposition nor the presence of microthrombi was correlated with aPL status. CONCLUSION Our findings suggest that activation of the classical pathway of complement plays a pathogenic role in the development of renal tissue injury leading to thrombosis, irrespective of the type of circulating antibodies present. Immunodetection of glomerular C4d deposition in renal biopsy samples could be a convenient method of identifying patients at risk of thrombotic microangiopathy.

Selective involvement of the amygdala in systemic lupus erythematosus.

Background Antibodies specifically affect the amygdala in a mouse model of systemic lupus erythematosus (SLE). The aim of our study was to investigate whether there is also specific involvement of the amygdala in human SLE. Methods and Findings We analyzed a group of 37 patients with neuropsychiatric SLE (NP-SLE), 21 patients with SLE, and a group of 12 healthy control participants with diffusion weighted imaging (DWI). In addition, in a subset of eight patients, plasma was available to determine their anti-NMDAR antibody status. From the structural magnetic resonance imaging data, the amygdala and the hippocampus were segmented, as well as the white and gray matter, and the apparent diffusion coefficient (ADC) was retrieved. ADC values between controls, patients with SLE, and patients with NP-SLE were tested using analysis of variance with post-hoc Bonferroni correction. No differences were found in the gray or white matter segments. The average ADC in the amygdala of patients with NP-SLE and SLE (940 × 10−6 mm2/s; p = 0.006 and 949 × 10−6 mm2/s; p = 0.019, respectively) was lower than in healthy control participants (1152 × 10−6 mm2/s). Mann-Whitney analysis revealed that the average ADC in the amygdala of patients with anti-NMDAR antibodies (n = 4; 802 × 10−6 mm2/s) was lower (p = 0.029) than the average ADC of patients without anti-NMDAR antibodies (n = 4; 979 × 10−6 mm2/s) and also lower (p = 0.001) than in healthy control participants. Conclusions This is the first study to our knowledge to observe damage in the amygdala in patients with SLE. Patients with SLE with anti-NMDAR antibodies had more severe damage in the amygdala compared to SLE patients without anti-NMDAR antibodies.

Anti-NMDA receptor autoantibodies in patients with systemic lupus erythematosus and their first-degree relatives.

The objective of this study is to investigate the presence of autoantibodies cross-reacting with the NR2 subunit of the N-methyl-d-aspartate (NMDA) glutamate receptor in plasma samples of patients with systemic lupus erythematosus (SLE), in their healthy first-degree relatives and in healthy unrelated individuals and to determine whether these autoantibodies are specific for lupus patients in general or for the subgroup of SLE patients with neuropsychiatric (NP) manifestations. Plasma samples were collected from 51 lupus patients (19 with and 32 without NP manifestations), 161 first-degree relatives and 55 healthy unrelated controls. Antibodies to a linear peptide of the NR2 subunit of the NMDA receptor were determined by enzyme-linked immunosorbent assay. A significant difference in mean antibody reactivity between SLE patients and healthy unrelated controls (P < 0.01) and between firstdegree relatives and healthy unrelated controls (P < 0.001) was found. No difference was found between lupus patients and their first-degree relatives or between lupus patients with and without NP symptoms. In this study, anti-NMDA receptor autoantibodies show more specificity for lupus patients (but not for selected patients with NP symptoms) and their first-degree relatives than for healthy controls, indicating a familial basis to mount an immune response to this peptide. Lupus (2007) 16, 329—334.

Tract-based spatial statistics on diffusion tensor imaging in systemic lupus erythematosus reveals localized involvement of white matter tracts

OBJECTIVE The aim of this study was to determine whether there are differences in white matter integrity between systemic lupus erythematosus (SLE) patients and healthy controls, as determined using tract-based spatial statistics (TBSS) analysis of diffusion tensor imaging data. METHODS Twelve patients with SLE (mean age 42 years [range 15-61 years]) diagnosed according to the American College of Rheumatology 1982 revised criteria for SLE and 28 healthy controls (mean age 46 years [range 21-61 years]) were included in the study. Magnetic resonance imaging was performed on a 3.0T scanner. Fractional anisotropy (FA) maps were calculated for each patient. TBSS analysis was used to compare the FA maps. The TBSS technique projects the FA data into a common space through the use of an initial approximate nonlinear registration, followed by projection onto an alignment-invariant tract representation (mean FA skeleton). The cluster results were corrected for multiple comparisons across space, and a threshold of significance of 0.05 was used. RESULTS The white matter of tracts in the inferior fronto-occipital fasciculus, the fasciculus uncinatus, as well as the fornix, the posterior limb of the internal capsule (corticospinal tract), and the anterior limb of the internal capsule (anterior thalamic radiation) of patients with SLE showed reduced integrity as compared with normal subjects. CONCLUSION In this preliminary study, the integrity of white matter tracts in areas around limbic structures and in the internal capsule was found to be reduced. Larger studies could improve our understanding of the pathologic mechanisms behind the reduced white matter tract integrity in SLE.

Neuropsychiatric manifestations in patients with systemic lupus erythematosus: epidemiology and radiology pointing to an immune-mediated cause

Background Different pathogenetic pathways have been proposed for neuropsychiatric (NP) manifestations in systemic lupus erythematosus (SLE). Objective To describe the patient characteristics of a large cohort of patients with SLE with NP manifestations (NPSLE) in a single centre and to review whether these and other data are compatible with immune-mediated mechanisms. Methods A total of 212 patients were identified from MRI scans of the brain ordered for suspected NPSLE. Data were collected from the medical records. NP syndromes were classified according to the American College of Rheumatology (ACR) nomenclature and case definitions. Results 155 patients fulfilled the criteria for SLE. In 102 patients NP manifestations were attributed to SLE itself (primary NPSLE) whereas, in the remaining patients, the NP symptoms were due to other causes. The median age at the time of SLE diagnosis in patients with primary NPSLE was 27.5 years and the median duration prior to NPSLE was 2.8 years. Forty patients (39%) had a NP manifestation in the first year of the disease. Cerebrovascular disease, cognitive dysfunction, seizures and headache were the most prevalent syndromes. In 47% of patients with primary NPSLE the MRI scan of the brain showed no abnormalities. Conclusions Most NP manifestations in SLE occur early in the disease. This finding, as well as data from quantitative imaging studies and recent pathological studies, point to an immune-mediated pathogenesis.

Mortality in neuropsychiatric systemic lupus erythematosus (NPSLE)

The standardized mortality ratio (SMR) for systemic lupus erythematosus (SLE) is three; SMR increases to six in case of renal involvement. Up to now data on survival in case of neuropsychiatric involvement in SLE (NPSLE) have been scarce, therefore we calculated an SMR for NPSLE. Furthermore, we identified characteristics that influenced survival by Cox regression analyses. All patients suspected of NPSLE in our center since 1989 were evaluated and included in this study when a diagnosis of primary NPSLE could be established. Patient’s life/death status was tracked using the civic registries. Thirty-two (19%) of the 169 included NPSLE patients died within a median follow-up period of six years (range 0.5–24 years). This resulted in a significantly increased mortality rate compared to the general population: SMR 9.5 (95% CI 6.7–13.5). Hazard ratios (HRs) were highest in patients with acute confusional state (HR 3.4) and older age at diagnosis of NPSLE (HR 1.1). A decreased mortality risk was seen with the prescription of antiplatelet therapy (HR 0.22). The time period in which NPSLE was diagnosed did not significantly influence survival. Most frequent causes of death were infection and NPSLE itself.

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.

TREX1 Gene Variant in Neuropsychiatric Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disorder with a complex genetic background. Some 14–75% of SLE patients report neurological and psychiatric symptoms and are diagnosed with neuropsychiatric-SLE (NPSLE).1 Many of these patients also have cerebral white matter hyperintensities (WMH). The aetiology and genetic background of NPSLE is largely unknown. In 2007, mutations in the TREX1 gene, encoding the major mammalian 3′-5′ DNA exonuclease, were identified in nine out of 417 SLE patients.2 In addition, TREX1 has been associated with disorders that are often associated with cerebral WMH, migraine(-like symptoms) and other manifestations of brain disease.3 4 Consequently, we considered TREX1 an excellent candidate for NPSLE. We scanned genomic DNA of 60 NPSLE patients (table 1) for exonic TREX1 mutations using direct sequencing,5 and identified a novel heterozygous p.Arg128His mutation in one NPSLE patient. This patient was admitted to our hospital …