The clinical significance of ubiquitin carboxyl hydrolase L1 and its autoantibody in neuropsychiatric systemic lupus erythematosus

OBJECTIVES

To identify specific cerebrospinal fluid (CSF) biomarkers for the diagnosis and disease severity evaluation of neuropsychiatric systemic lupus erythematosus (NPSLE).

METHODS

Patients presented with neuropsychiatric symptoms were recruited and categorised as 36 NPSLE, 19 SLE controls, 4 other connective tissue disease (CTD) controls and 10 nervous system disorder (NSD) controls. The NPSLE group consisted of severe NPSLE (sNPSLE) and mild NPSLE (mNPSLE). Potential biomarkers were determined by Luminex multiplex assay and enzyme-linked immunosorbent assay.

RESULTS

1) Among a variety of neurological disease-related proteins, only ubiquitin carboxyl hydrolase L1 (UCH-L1) levels were significantly elevated in the CSF samples of sNPSLE patients compared with those of mNPSLE patients (p=0.020) and SLE controls (p=0.037). CSF UCH-L1 levels were significantly positively correlated with SLE disease activity index and overlap number of NPSLE manifestations. 2) CSF anti-UCH-L1 autoantibodies were significantly elevated in patients with NPSLE in comparison to all of the control groups, with a sensitivity of 53% and a specificity of 91% for NPSLE. CSF anti-UCH-L1 levels were associated with organ involvement and were positively correlated with serum anti-UCH-L1 levels in the NPSLE patients (r=0.4551, p=0.0382).

CONCLUSIONS

Anti-UCH-L1 is a promising CSF biomarker for NPSLE diagnosis with high specificity, and the elevated levels of CSF UCH-L1 reflect the clinical severity of NPSLE. The elevation of UCH-L1 and its autoantibody in NPSLE patients showed us novel aetiological insights on NPSLE.

Cognitive impairment, event-related potentials and immunological status in patients with systemic lupus erythematosus

BACKGROUND

Cognitive impairment (CI) is a frequent problem in lupus patients, regardless of their overt neuropsychiatric (NP) involvement.

OBJECTIVES

The aim of our study was to test cognitive abilities in systemic lupus erythematosus (SLE) patients by means of neuropsychological testing and event-related potentials (ERPs), and to search for their cognitive abilities correlations with a wide range of auto-antibodies.

MATERIAL AND METHODS

A total of 37 SLE patients were subjected to a battery of neuropsychological tests, recommended by the American College of Rheumatology (ACR), and to ERPs. They were also tested for a wide range of auto-antibodies (anti-cardiolipin (aCL), anti-β2-glycoprotein I (anti-β2-GPI), lupus anticoagulant, anti-dsDNA, anti-nucleosome, anti-ribosomal P (anti-Rib-P), anti-ganglioside, anti-Ro/SS-A, and anti-La/SS-B.

RESULTS

Cognitive impairment was found in 35% of patients, mostly with NP SLE (NPSLE), and was associated with higher disease activity, measured by the SLE Disease Activity Index (SLEDAI), and with a longer duration of central nervous system (CNS) involvement. There were no differences in the immunological status between CI patients and those without cognitive decline, but some antibodies were correlated with worse results in certain neuropsychological tests (anti-dsDNA and worse results of Rey Complex Figure Test - RCFTc for copying and RCFTr for recall, and of verbal fluency test (VFT); aCL IgG and worse results in Digit Span (DS) and in RCFTc). Event-related potentials showed prolonged N200 and P300 latencies in SLE patients in comparison to controls, but no differences were found between SLE and NPSLE patients. Mean P300 latency was significantly longer in patients without anti-nucleosome antibodies.

CONCLUSIONS

Event-related potentials can be used as a complementary tool in assessing CI in SLE patients. The immunological status of patients with CI did not differ from that of patients without cognitive problems.

Role of serum autoantibodies in blood brain barrier damages in neuropsychiatric systemic lupus erythematosus

OBJECTIVES

The present study was carried out to elucidate the roles of serum autoantibodies in the development of blood-brain barrier (BBB) damages in neuropsychiatric systemic lupus erythematosus (NPSLE).

METHODS

Paired serum and CSF samples were obtained from 101 SLE patients when they presented active neuropsychiatric manifestations (69 patients with diffuse psychiatric/neuropsychological syndromes [diffuse NPSLE] and 32 patients with neurologic syndromes or peripheral neuropathy [focal NPSLE]). IgG anti-NR2 subunit of NMDA receptor (anti-NR2), anti-Sm, anti-ribosomal P and IgG anti-cardiolipin in sera and albumin in CSF and sera were measured by ELISA. Blood-brain barrier (BBB) function was evaluated by Q albumin (CSF/serum albumin quotient x 1,000).

RESULTS

Q albumin was significantly higher in acute confusional state (ACS) than in non-ACS diffuse NPSLE (anxiety disorder, cognitive dysfunction, mood disorder and psychosis) or in focal NPSLE. Anti-Sm, but not anti-NR2, anti-P or anticardiolipin, was significantly elevated in ACS compared with the other 2 groups of NPSLE, although serum anti-NR2 was significantly higher in ACS than that in focal NPSLE. Multiple regression analysis confirmed the significant contribution of anti-Sm (p=0.0040), but not anti-NR2 (p=0.5023), anti-P (p=0.2651), or anti-cardiolipin (p=0.6769) in the elevation of Q albumin.

CONCLUSIONS

The data demonstrate that serum anti-Sm antibodies play a most important role in the disruption of BBB in NPSLE.

Evaluation of blood-brain barrier function by quotient alpha2 macroglobulin and its relationship with interleukin-6 and complement component 3 levels in neuropsychiatric systemic lupus erythematosus

Although quotient of alpha2 macroglobulin (Qα2MG) was previously reported to be useful for the evaluation of blood–brain barrier (BBB) function, it is not commonly used. We therefore evaluated BBB function among the various subsets of neuropsychiatric systemic lupus erythematosus (NPSLE) using quotient Q α2MG. Furthermore, we determined the correlation between Q α2MG and cerebrospinal (CSF) interleukin (IL)-6 level and quotient complement component 3 (Q C3). To determine intrathecal production of C3, the C3 index (Q C3/Q α2MG) was also calculated. Fifty-six patients with SLE were included in this study. Of these, 48 were diagnosed with NPSLE, consisting of 30 diffuse NPSLE patients (acute confusional state (ACS): n = 14, non-ACS: n = 16) and 18 patients with focal NPSLE. CSF IL-6 concentration, and paired serum and CSF levels of α2MG and C3, were measured by enzyme-linked immuno solvent assay (ELISA). The Q α2MG, Q C3, and C3 index were then calculated. Q α2MG, Q C3, and IL-6 concentrations in the CSF were significantly elevated in NPSLE compared with non-NPSLE. Among the subsets of NPSLE, significant increases in Q α2MG, CSF IL-6, and Q C3 were observed in ACS compared with non-ACS or focal NPSLE. There was a positive correlation between CSF IL-6 level and Q α2MG, as well as between Q C3 and Q α2MG, in diffuse NPSLE. There were no significant differences in C3 index between NPSLE and non-NPSLE, as well as among the subgroups of NPSLE. Our study suggests that BBB disruption is present in ACS, and elevated levels of IL-6 and C3 in CSF in diffuse NPSLE, especially in ACS, might result from their entry to the CSF from the systemic circulation through the damaged BBB, as well as increased intrathecal production. Furthermore, Q α2MG might be useful for the evaluation of BBB integrity.

Anti-ribosomal P-protein and its role in psychiatric manifestations of systemic lupus erythematosus: myth or reality?

Systemic lupus erythematosus (SLE) is an autoimmune disease that may involve the central nervous system (CNS) resulting in neuropsychiatric manifestations. The associated psychiatric disorders include depression, psychosis, mood disorders, anxiety, cognitive dysfunction, and delirium/encephalopathy. Several autoantibodies may play a role in the pathogenesis of psychiatric complications of SLE, particularly antibodies against ribosomal P-proteins (anti-P) and possibly antibodies against endothelial cells (AECA). The reported prevalence of anti-P is highly variable in SLE patients and is dependent on different ethnic backgrounds, sensitivity and specificity of the assays employed for autoantibody detection, and the time at which sera were analysed in relation to the clinical event. Controversial data exist on the association of anti-P with psychiatric manifestations of SLE. These autoantibodies have been suggested to be specific markers of the psychiatric manifestations of SLE, particularly of the psychosis and depression, and the antibody level varied with the clinical activity of the disease. Some studies have confirmed the hypothesis of an association of anti-P antibodies with psychiatric manifestations of neuropsychiatric SLE (NPSLE) while others have disputed this relationship. This review summarizes the recent studies about relationship between anti-P antibodies and psychiatric manifestation of SLE.

Autoantibody profiling on human proteome microarray for biomarker discovery in cerebrospinal fluid and sera of neuropsychiatric lupus

Autoantibodies in cerebrospinal fluid (CSF) from patients with neuropsychiatric systemic lupus erythematosus (NPSLE) may be potential biomarkers for prediction, diagnosis, or prognosis of NPSLE. We used a human proteome microarray with~17,000 unique full-length human proteins to investigate autoantibodies associated with NPSLE. Twenty-nine CSF specimens from 12 NPSLE, 7 non-NPSLE, and 10 control (non-systemic lupus erythematosus)patients were screened for NPSLE-associated autoantibodies with proteome microarrays. A focused autoantigen microarray of candidate NPSLE autoantigens was applied to profile a larger cohort of CSF with patient-matched sera. We identified 137 autoantigens associated with NPSLE. Ingenuity Pathway Analysis revealed that these autoantigens were enriched for functions involved in neurological diseases (score = 43).Anti-proliferating cell nuclear antigen (PCNA) was found in the CSF of NPSLE and non-NPSLE patients. The positive rates of 4 autoantibodies in CSF specimens were significantly different between the SLE (i.e., NPSLE and non-NPSLE) and control groups: anti-ribosomal protein RPLP0, anti-RPLP1, anti-RPLP2, and anti-TROVE2 (also known as anti-Ro/SS-A). The positive rate for anti-SS-A associated with NPSLE was higher than that for non-NPSLE (31.11% cf. 10.71%; P = 0.045).Further analysis showed that anti-SS-A in CSF specimens was related to neuropsychiatric syndromes of the central nervous system in SLE (P = 0.009). Analysis with Spearman’s rank correlation coefficient indicated that the titers of anti-RPLP2 and anti-SS-A in paired CSF and serum specimens significantly correlated. Human proteome microarrays offer a powerful platform to discover novel autoantibodies in CSF samples. Anti-SS-A autoantibodies may be potential CSF markers for NPSLE.

Valproate-induced hyperammonaemia superimposed upon severe neuropsychiatric lupus: a case report and review of the literature

This paper presents a case of systemic lupus erythematosus (SLE) with neuropsychiatric features, where the outcome was influenced by the development of hyperammonaemia, probably induced by sodium valproate. A case of severe SLE occurring in a 20-year-old Maori girl is described. Her disease had been characterised by neuropsychiatric features for several years, culminating in persistent seizure activity at the time of her final presentation. Her management with anticonvulsants was complicated by the development of intractable hyperammonaemia which contributed to irreversible clinical deterioration. We have reviewed the English literature for reports of valproate-related hyperammonaemia which has often been described in the setting of seizure and mood disorders. This is the first case where it has been reported, superimposed upon severe neuropsychiatric SLE (NP-SLE). The mechanism by which valproate induces hyperammonaemia remains incompletely understood but is likely to relate to the urea cycle. Under normal metabolic conditions, acyl-CoA is transported into the mitochondria via a carnitine transport system. It is then converted to acetyl-CoA via β-oxidation and eventually to N-acetyl glutamate. This pathway can be interrupted by the introduction of sodium valproate, leading to a reduction of free coenzyme A, acetyl-CoA and carnitine, and resulting in the decreased availability of cofactors necessary for the function of the urea cycle. As this is the primary means of ammonia metabolism, serious elevation in serum ammonia levels may occur in patients on this anticonvulsant medication. In this patient with active NP-SLE, the combined autoimmune and metabolic brain insult contributed to a fatal outcome.

Lymphopenia is associated with neuropsychiatric manifestations and disease activity in paediatric systemic lupus erythematosus patients

OBJECTIVES

To investigate if lymphopenia is associated with clinical manifestations, disease activity and prognosis in systemic lupus erythematosus (SLE).

METHODS

The charts of 186 paediatric patients with SLE diagnosed between 1985 and 2006 in a medical centre were retrospectively reviewed. Lymphocyte counts were recorded at the time of SLE diagnosis and SLE flares. Global disease activity was quantified by the SLE Disease Activity Index (SLEDAI). Cumulative organ damage was assessed by the ACR/Systemic Lupus International Collaborating Clinics (SLICC) damage index.

RESULTS

Lymphopenia (<1500/mm(3)) and marked lymphopenia (<500/mm(3)) was observed in 62.8 and 12.2% at the time of SLE diagnosis. At the time of SLE diagnosis, lymphopenia was significantly associated with oral ulcers, leucopenia, anti-dsDNA antibodies and C4 decrease. At the time of flares, lymphopenia was significantly associated with anti-dsDNA antibodies, methylprednisolone pulse therapy, disease activity and organ damage. Using multivariate logistic regression, marked lymphopenia was independently associated with neuropsychiatric manifestations [odds ratio (OR) 7.41, 95% confidence interval (CI) 1.99-27.0], and protective from LN (OR 0.13, 95% CI 0.03-0.53).

CONCLUSIONS

Lymphopenia at SLE flares is associated with disease activity and organ damage. Marked lymphopenia is independently associated with neuropsychiatric manifestations.

[Clinical significance of neuro-reactive autoantibodies in neuro-psychiatric systemic lupus erythematosus]

OBJECTIVE

To investigate the clinical significance of specific/non-specific neuro-reactive autoantibodies in the pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE).

METHODS

Samples of serum and cerebrospinal fluid (CSF) were collected from 25 NPSLE patients, 11 patients with SLE complicated with central nervous system (CNS) infection (control group 1), and 10 SLE patients without CNS infection (non-NPSLE, control group 2)) were detected, Indirect immunofluorescence technique was used to detect the anti-nuclear antibody (ANA) based on the slides with human epithelium cell of laryngocarcinoma of the line Hep-2 or on the slides with cerebellum and peripheral nerve of monkey, he type of immunofluorescence were assayed.

RESULTS

The percentages of ANA positive serum of the NPSLE, SLE control 1, and SLE control 2 groups were 92% (23/25), 100% (11/11), and 100% (10/10) respectively without significant differences between any 2 groups (all P > 0.05). The percentage of ANA positive CSF of the NPSLE was 60% (15/25), significantly higher than that of the SLE control group 1 (27%, 3/11, P < 0.01). There was no significant correlation between the titer of serum ANA and the titer of CSF ANA (P > 0.05). The positive rate of neuro-reactive autoantibodies was 40% (10/25), significantly higher than those of the 2 control groups (both 0, both P > 0.001).

CONCLUSION

(1) The ANA positivity in the CSF of the NPSLE group is associated with the disease activity and CNS involvement, the higher the titer of autoantibodies the severe the clinical manifestations. (2) The neuro-reactive autoantibodies in the serum may associate with NPSLE with still unknown mechanism.

Raised serum S100B protein levels in neuropsychiatric lupus

OBJECTIVE

To test serum S100B protein levels in patients with and without neuropsychiatric systemic lupus erythematosus (NPSLE) and controls.

METHODS

87 patients with SLE, 23 with and 64 without neuropsychiatric involvement, and 25 control subjects were prospectively evaluated. NPSLE diagnosis was made according to the American College of Rheumatology nomenclature and case definitions for neuropsychiatric lupus syndromes. Serum S100B protein levels were determined with a luminescence immunoassay. Statistical analysis was performed using Mann-Whitney and Kruskal-Wallis tests.

RESULTS

Among the patients with NPSLE, 9 presented psychosis; 4, cranial neuropathy; 3, cerebrovascular disease; 1, seizures; 1, chorea; 1, peripheral polyneuropathy; 1, multiplex mononeuropathy; 3, dementia. Serum concentrations of S100B protein were significantly higher in patients with NPSLE (median 0.164 ng/ml, interquartile range 0.113-0.332) than in non-NPSLE patients (0.062 ng/ml, 0.026-0.109) and controls (0.088 ng/ml, 0.013-0.124) (p<0.001). Patients with anti-dsDNA antibodies had higher S100B protein levels (p = 0.001). No significant associations were found of lupus activity (among non-NPSLE cases), antiphospholipid antibodies, and reduced complement levels with S100B concentration.

CONCLUSIONS

Serum S100B protein level is raised in NPSLE, reflecting continuing neurological damage. The association of anti-dsDNA antibodies with higher S100B protein concentration deserves further study.

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.

Cerebral and corpus callosum atrophy in systemic lupus erythematosus

OBJECTIVE

To determine cerebral and corpus callosum volumes in patients with systemic lupus erythematosus (SLE), using semiautomatic magnetic resonance imaging (MRI) volumetric measurements, and to determine possible relationships between a reduction in cerebral volume and disease duration, total corticosteroid dose, neuropsychiatric manifestations, and the presence of antiphospholipid antibodies.

METHODS

We studied 115 consecutive patients with SLE and 44 healthy volunteers. A complete clinical, laboratory, and neurologic evaluation was performed. MRI scans were obtained through a standardized protocol. Sagittal T1-weighted images were used for semiautomatic volumetric measurements. We compared SLE patients with controls using the 2-sample t-test. Analysis of variance was used to test for differences between groups, followed by Tukey's post hoc test for pairwise comparisons, when necessary. Linear regression was used to analyze the association between cerebral atrophy and disease duration and total corticosteroid dose.

RESULTS

Cerebral and corpus callosum volumes were significantly smaller in patients with SLE compared with healthy volunteers (P < 0.001). Reduced cerebral and corpus callosum volumes were related to disease duration (P < 0.001). Patients with a history of central nervous system (CNS) involvement more frequently had a reduction in cerebral and corpus callosum volumes (P < 0.001). Patients with cognitive impairment had significantly reduced corpus callosum and cerebral volumes when compared with SLE patients without cognitive impairment (P = 0.001). Cerebral and corpus callosum volumes were not associated with the total corticosteroid dose or the presence of antiphospholipid antibodies.

CONCLUSION

In patients with SLE, a reduction in cerebral and corpus callosum volumes is associated with disease duration, a history of CNS involvement, and cognitive impairment. The total corticosteroid dose and the presence of antiphospholipid antibodies were not associated with more pronounced atrophy.

Elevated levels of soluble fractalkine in active systemic lupus erythematosus: potential involvement in neuropsychiatric manifestations

OBJECTIVE

To determine levels of the soluble form of the chemokine fractalkine (sFkn) and its receptor, CX(3)CR1, in patients with systemic lupus erythematosus (SLE) with neuropsychiatric involvement (NPSLE) and in SLE patients without neuropsychiatric involvement, and to assess their relationship with disease activity and organ damage.

METHODS

Levels of sFkn in serum and cerebrospinal fluid (CSF) were measured by enzyme-linked immunosorbent assay. Expression of Fkn and CX(3)CR1 was quantified using real-time polymerase chain reaction. Surface expression of CX(3)CR1 on peripheral blood mononuclear cells (PBMCs) was determined by flow cytometry. Disease activity and organ damage were assessed using the SLE Disease Activity Index (SLEDAI) and the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index, respectively.

RESULTS

Serum sFkn levels were significantly higher in patients with SLE than in patients with rheumatoid arthritis (RA) or healthy controls. In addition, significant correlations between serum sFkn levels and the SLEDAI, the SLICC/ACR Damage Index, anti-double-stranded DNA and anti-Sm antibody titers, immune complex levels (C1q), and serum complement levels (CH50) were observed. Expression of CX(3)CR1 was significantly greater in PBMCs from patients with active SLE than in those from RA patients or healthy controls. Levels of sFkn were also significantly higher in CSF from untreated patients with newly diagnosed NPSLE than in SLE patients without neuropsychiatric involvement; treatment reduced both serum and CSF levels of sFkn in patients with SLE.

CONCLUSION

Soluble Fkn and CX(3)CR1 may play key roles in the pathogenesis of SLE, including the neuropsychiatric involvement. Soluble Fkn is also a serologic marker of disease activity and organ damage in patients with SLE, and its measurement in CSF may be useful for the diagnosis of NPSLE and followup of patients with NPSLE.

Behavioral heterogeneity in an animal model of neuropsychiatric lupus

BACKGROUND

Various psychiatric manifestations of unknown etiology are common in systemic autoimmune disease lupus erythematosus (SLE). Profound heterogeneity at clinical and neuropathological levels suggests distinct subpopulations of SLE patients and multiple mechanisms in the pathogenesis of aberrant behavior. Using inbred mice prone to SLE-like condition, we presently examine whether subpopulations of diseased mice can be identified on the basis of their behavioral performance.

METHODS

Hierarchical cluster analysis was used to classify 105 MRL-lpr males into clusters. Multivariate analysis of variance (MANOVA) and discriminant function analysis were used to detect overall differences and identify discriminative variables.

RESULTS

Cluster 1 was characterized by blunted responsiveness to palatable stimulation, as well as increased spleen mass and serum levels of interleukin-1. Cluster 2 comprised of animals with reduced ambulation speed and enlarged spleen. Mice from cluster 3 showed profound dilatation of brain ventricles, reduced brain mass, impaired nutrition and performance in task reflective of emotional reactivity.

CONCLUSIONS

Present results suggest that systemic autoimmunity compromises brain function via non-Mendelian mechanisms. Although neuroactive cytokines may impair reward systems, brain atrophy seems to underlie deficits in ingestive behavior and emotional reactivity. This study supports the hypothesis that multiple neuroimmunological pathways are involved in the etiology of aberrant behavior during SLE-like disease.

Serum neopterin, tumor necrosis factor-α and soluble tumor necrosis factor receptor II (p75) levels and disease activity in Egyptian female patients with systemic lupus erythematosus

OBJECTIVE

To determine the clinical value of assaying serum levels of neopterin, tumor necrosis factor-alpha (TNF-alpha) and soluble tumor necrosis factor receptor II (p75) (sTNFRII) in patients with systemic lupus erythematosus (SLE), manifested clinically with lupus nephritis (LN), neuropsychiatric lupus erythematosus (NPLE), and/or vasculitis compared with established parameters (complements C3 and C4).

PATIENTS AND METHODS

Serum concentrations of neopterin, TNF-alpha and sTNFRII were studied in 40 female patients with SLE at various degrees of disease activity and in 10 healthy controls, matched for age and sex, using an ELISA kit. Disease activity was assessed by the SLE disease activity index (SLEDAI) score. Thirty-five, 30 and 28 of our patients presented with LN, NPLE and/or vasculitis, respectively, as the main clinical manifestation.

RESULTS

Serum levels of neopterin, TNF-alpha and sTNFRII were significantly increased, while the TNF-alpha/sTNFRII ratio, C3 and C4 levels of SLE patients were significantly lower than those of healthy controls. Neopterin and sTNFRII were the only parameters that showed significantly higher levels in SLE patients with mild activity compared to normal subjects and were the only parameters that showed a significant elevation in membranous nephritis and in mild NPLE compared to patients without nephritis and NPLE. Patients with vasculitis had significant elevation of serum neopterin, TNF-alpha and sTNFRII levels compared to patients without vasculitis. We found significant correlations between all measured variables and the SLEDAI score. Also, serum neopterin levels showed significant positive correlation with serum TNF-alpha, sTNFRII and TNF-alpha/sTNFRII levels. Serum neopterin and sTNFRII could be used to identify SLE patients from normals with a sensitivity and specificity of 100%. Multivariate linear regression analysis showed that serum sTNFRII was the only significant independent variable among parameters for prediction of SLE disease activity.

CONCLUSION

We suggest that serum sTNFRII and neopterin are more sensitive markers of disease activity than TNF-alpha, C3 or C4. However, sTNFRII may be a clinically useful independent marker for prediction of SLE disease activity and to differentiate normal subjects from those having mild SLE.

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.

The heterogeneity of neuropsychiatric systemic lupus erythematosus is reflected in lack of association with cerebrospinal fluid cytokine profiles

The objective was to study the occurrence of autoantibodies and cytokines in serum and cerebrospinal fluid (CSF) in neuropsychiatric systemic lupus erythematosus (NPSLE). In total, 28 consecutive patients with NPSLE and 16 systemic lupus erythematosus (SLE) patients without neuropsychiatric involvement (non-NPSLE) were studied. IFN-alpha, IL-6, IL-10, soluble terminal complement complex (TCC), anti-ribosomal P protein antibodies (anti-P) and anti-cardiolipin antibodies (aCL) were measured in serum and CSF by immunoassays. Analyses of white blood cell differential count, CSF-albumin/serum-albumin ratio, IgG-index in CSF and isoelectric focusing in serum and CSF were also performed. CSF specimens from 23 healthy individuals were used as controls. IFN-alpha was elevated in the CSF of 5 of 28 NPSLE patients compared to three of 14 among the non-NPSLE patients. IL-6 was elevated in CSF in three of 26 NPSLE patients. Normal concentration of IL-10 was found in CSF in all 27 NPSLE-patients analysed. IFN-alpha in serum was elevated in 18 of 28 NPSLE patients. No distinct clinical phenotype was related to elevated cytokine concentration in serum or CSF. One patient with cerebral involvement complicated by progressive multifocal leukoencephalopathy displayed a very high IFN-alpha concentration in serum. High concentration of TCC was present in CSF from only one patient with systemic vasculitis and focal cerebral symptoms. In conclusion, the results of this study suggest that the diagnostic value of serum and CSF concentrations of IFN-alpha, IL-10, IL-6 and TCC is limited in unselected neuropsychiatric SLE, probably due to the heterogeneity of NPSLE pathogenesis.

Leukoencephalopathy and chronic pancreatitis as concomitant manifestations of systemic lupus erythematosus related to anticardiolipin antibodies

Symptoms of leukoencephalopathy led to hospital admission of a 59-year-old woman. In addition, a tumor of unknown nature in the pancreas was identified by abdominal ultrasound and CT scan. Following explorative laparotomy and pancreas tail resection, histopathologic analysis revealed a pancreatic pseudotumor with chronic fibrotic pancreatitis. Systemic lupus erythematosus (SLE) was diagnosed due to the presence of antinuclear antibodies (ANA) in serum, antiphospholipid antibodies, and involvement of the central nervous system. Leukoencephalopathy related to anticardiolipin antibodies in serum is a known but rare manifestation of SLE. The concomitant occurrence of chronic pancreatitis can be caused by the development of SLE-induced vasculitis in the pancreas. Subsequent complications of pancreatitis are responsible for the critical, life-threatening state of these patients and may be prevented by early identification of anticardiolipin antibodies and therapy for SLE.

MRI findings in central nervous system systemic lupus erythematosus are associated with immunoserological parameters and hypertension

Involvement of the brain is one of the most important complications of systemic lupus erythematosus (SLE). To investigate the correlation between abnormal cranial MRI findings and age, duration of SLE, neuropsychiatric (NP) manifestations, hypertensive status, and the presence of antiphospholipid antibodies (PA) in patients with SLE we evaluated the MRI results of 81 SLE patients in nine NP clinical subgroups.Immunoserological status was described by the presence of lupus anticoagulant (LA), and anticardiolipin antibodies (aCL). The MRI findings were categorized as normal [41], cerebral atrophy [15], small subcortical hyperintensity [7], and infarct larger than 10mm [18]. Mean age differed among the clinical subgroups (ANOVA, p = 0.002), whereas there was no age difference among the subgroups based on MRI and immunoserological results. Patients with hypertension (33/81) were a mean of 6 years older at the time of examination (p = 0.033) and had stroke more frequently, than normotensive ones (p = 0.0015). MRI abnormalities were more frequent in patients with LA positivity (p < 0.01) than in those without these antibodies, and in the hypertensive than in the normotensive subgroup (p = 0.00041). The presence of PA was associated with abnormal MRI even after controlling for the effect of age and hypertensive status (p = 0.011). In our study the MRI findings in central nervous system SLE were independent of the age of patients and the age at the diagnosis of SLE, and were not influenced by the duration of SLE; however, they were associated with immunoserological parameters and hypertension.

Kinins and cytokines in plasma and cerebrospinal fluid of patients with neuropsychiatric lupus

OBJECTIVE

To evaluate the kinin system components and selected cytokines in plasma and cerebrospinal fluid (CSF) of patients with neuropsychiatric lupus (NPL).

METHODS

We studied 29 women with active NPL and 29 healthy women matched to patients for age. Low (LKg) and high molecular weight kininogen (HKg) and cytokine concentrations [interleukin 1beta (IL-1beta), IL-6, IL-8, IL-10, and tumor necrosis factor-a (TNF-a)] were determined by ELISA. The activities of tissue kallikrein, plasma prekallikrein, and kininase II were assayed by their action on selective substrates.

RESULTS

Compared to controls, patients with NPL presented increased plasma and CSF levels of LKg, HKg, and prekallikrein, increased activity of tissue kallikrein and kininase II, and increased levels of IL-6, IL-10, and TNF-a (p < 0.001 each comparison). IL-1beta levels were increased in patient plasma (p < 0.001), whereas plasma IL-8 levels did not differ from controls. IL-1beta and IL-8 were not detected in CSF of patients or controls.

CONCLUSION

The increased levels of kininogen fractions, kallikreins, and kininase II in patient plasma and CSF indicate overactivity of the kinin system, suggesting intense kinin production. Since kinins may induce the production of proinflammatory cytokines including IL-1beta, IL-6, and TNF-a, these findings support the participation of kinins and cytokines in the acute manifestations of NPL. Most of the variables evaluated in patients' CSF increased proportionally in relation to plasma levels. In contrast, the activity of tissue kallikrein in patient CSF increased out of proportion to plasma levels, appearing to be locally synthesized in response to brain involvement.

Increased lymphocyte death by neglect-apoptosis is associated with lymphopenia and autoantibodies in lupus patients presenting with neuropsychiatric manifestations

To evaluate lymphocyte death by neglect-apoptosis features in systemic lupus erythematosus (SLE) patients presenting with neuropsychiatric (NPSLE) involvement we studied 40 SLE patients with active disease, 20 with and 20 without neuropsychiatric manifestations, and 20 control individuals. Lymphocyte apoptosis was evaluated by means of DNA staining using flow cytometry, immediately after cell isolation and after incubation with culture medium or autologous serum. Compared with controls, NPSLE and non-NPSLE patients exhibited increased rates of neglect-apoptosis immediately after cell isolation. Only NPSLE patients exhibited an increased neglect-apoptosis rate after incubation with culture medium; however, the neglect-apoptosis rate was associated with lymphopenia in both series of patients. After lymphocyte incubation with autologous serum, only NPSLE patients exhibited a significant negative correlation between the neglect-apoptosis rate and the number of peripheral lymphocytes. The incubation of lymphocytes with autologous serum containing antiphospholipid or anti-SSA/Ro antibodies significantly increased the neglect-apoptosis in NPSLE when compared with non-NPSLE patients with a similar autoantibody profile. In conclusion, NPSLE and non-NPSLE patients shared several abnormalities in terms of lymphocyte neglect-apoptosis. Peculiar findings were observed in NPSLE patients particularly after incubation with autologous serum, such as the fact that the increased lymphocyte death by neglect-apoptosis was associated with lymphopenia and with the presence of antiphospholipid and anti-SSA/Ro antibodies.

Autoantibodies in neuropsychiatric lupus

The American College of Rheumatology presented a consensus document in 1999 proposing the classification of 19 different syndromes defined by neurological and psychiatric manifestations of systemic lupus erythematosus (SLE). The detection of autoantibodies in patient's serum or cerebrospinal fluid has not been used as diagnostic markers for the proposed neuropsychiatric lupus classifications as their disease associations remain highly contentious. Autoantibodies detected in the serum and/or cerebrospinal fluid, that have been reported to segregate with patients presenting with neuropsychiatric lupus include: (1) anti-neuronal antibodies, (2) brain-lymphocyte cross-reactive antibodies, (3) anti-ribosomal P antibodies, (4) anti-phospholipid antibodies and (5) anti-ganglioside antibodies. Tests for anti-neuronal, anti-brain-lymphocyte cross-reactive and anti-ganglioside antibodies remain highly specialized whereas tests for ribosomal P antibodies and for antiphospholipid antibodies are currently routinely available in most diagnostic laboratories. Anti-ribosomal antibodies segregate with SLE. Antiphospholipid P antibodies are markers for the antiphospholipid syndrome. This syndrome may be associated with another disease, commonly SLE. In this setting, neuropsychiatric manifestations in SLE may arise as a consequence of thrombotic episodes involving the cerebral vasculature. There is a pressing need for antibodies to ribosomal P and to phospholipids to be standardized for routine diagnostic application. We conclude that the search for specific antibody marker(s) that can be applied for the routine laboratory diagnosis for neuropsychiatric lupus remains elusive.

Echolalia as a novel manifestation of neuropsychiatric systemic lupus erythematosus

"That tongue of yours, by which I have been tricked, shall have its power curtailed and enjoy the briefest use of speech." With these words, Hera, of Greek mythology, deprived the nymph Echo of spontaneous speech, constraining her instead to merely repeating the words of others. Echolalia, which derives from the word "echo," is disordered speech in which an individual persistently repeats what is heard. Echolalia has been described in patients with a number of neuropsychiatric illnesses including autism and Tourette's syndrome. Neuropsychiatric systemic lupus erythematosus (NPSLE) is a heterogeneous disease with protean manifestations that may occur in approximately 25% to 50% of patients with systemic lupus erythematosus (SLE). Although the most common manifestations include cognitive dysfunction (50%) and seizures (20%), NPSLE may also present as peripheral neuropathy (15%), psychosis (10%), or other central nervous system abnormalities. We report the case of a 57-year-old woman with SLE and echolalia.

Soluble L-selectin levels in serum and cerebrospinal fluid in patients with multiple sclerosis and systemic lupus erythematosus

Soluble L-selectin (sL-selectin) concentrations were measured in paired samples of serum and cerebrospinal fluid by an ELISA method. Patients with several forms of multiple sclerosis (MS) and systemic lupus erythematosus with central nervous system involvement (SLE-CNS) were investigated. Elevated CSF sL-selectin concentrations were found in patients with SLE-CNS (7.62 +/- 3.31 ng/ml) and with relapsing-remitting form of MS (6.99 +/- 4.72 ng/ml) compared to the control group (4.00 +/- 0.95 ng/ml). The data presented suggest some similarities between inflammatory/immunological events in the central nervous system in patients with SLE-CNS and relapsing-remitting form of MS. Immunological heterogeneity in MS is suspected.