Evoked potential studies in the antiphospholipid syndrome: differential diagnosis from multiple sclerosis

Single-Trial Visual Evoked Potential Extraction Using Partial Least-Squares-Based Approach

A single-trial extraction of a visual evoked potential (VEP) signal based on the partial least-squares (PLS) regression method has been proposed in this paper. This paper has focused on the extraction and estimation of the latencies of P100, P200, P300, N75, and N135 in the artificial electroencephalograph (EEG) signal. The real EEG signal obtained from the hospital was only concentrated on the P100. The performance of the PLS has been evaluated mainly on the basis of latency error rate of the peaks for the artificial EEG signal, and the mean peak detection and standard deviation for the real EEG signal. The simulation results show that the proposed PLS algorithm is capable of reconstructing the EEG signal into its desired shape of the ideal VEP. For P100, the proposed PLS algorithm is able to provide comparable results to the generalized eigenvalue decomposition (GEVD) algorithm, which alters (prewhitens) the EEG input signal using the prestimulation EEG signal. It has also shown better performance for later peaks (P200 and P300). The PLS outperformed not only in positive peaks but also in N75. In P100, the PLS was comparable with the GEVD although N135 was better estimated by GEVD. The proposed PLS algorithm is comparable to GEVD given that PLS does not alter the EEG input signal. The PLS algorithm gives the best estimate to multitrial ensemble averaging. This research offers benefits such as avoiding patient's fatigue during VEP test measurement in the hospital, in BCI applications and in EEG-fMRI integration.

Hughes syndrome and Multiple sclerosis

Multiple sclerosis (MS) and antiphospholipid syndrome (APS) share common clinical, laboratory and radiological features. We reviewed all the English papers on MS and APS published in the literature from 1965 to 2014 using PubMed and Google Scholar. We found that APS can mimic antiphospholipid antibodies (aPL)-positive MS in many ways in its clinical presentation. Nevertheless, APS diagnosis, clinical manifestations and management differ from those of MS. aPL were found in MS patients with titers ranging from 2% to 88%. The distribution and volume of lesions on magnetic resonance imaging (MRI) may help to differentiate MS from primary APS. In addition, atypical MS presentation can guide physicians toward an alternative diagnosis, especially when features of thrombosis and/or history of connective tissue disease are present. In that case, an anticoagulation trial could be worthwhile.

Demyelinating disease in SLE: is it multiple sclerosis or lupus?

Among the 12 systemic lupus erythematosus (SLE)-related central nervous system (CNS) syndromes defined by the American College of Rheumatology (ACR), demyelinating syndrome and myelopathy are two of the less prevalent and more poorly understood ones. One important issue concerning demyelinating disease in SLE is that it can be easily misdiagnosed with other central nervous system demyelinating disorders such as multiple sclerosis (MS). A clinically isolated neurological syndrome can be the presenting feature before other concomitant symptoms of SLE appear or definite MS is diagnosed. Although challenging, some diagnostic tests used in clinical practice and research may help to differentiate between these entities. These tests have improved the understanding of the pathogenesis in these diseases, but some points, such as the role of antiphospholipid antibodies in SLE-associated transverse myelitis, remain unclear and are a matter of ongoing debate. This review discusses clinical, pathophysiological, radiological and therapeutic concepts of demyelinating disease of the CNS in SLE, focussing on its differentiation from MS and its relation with other CNS demyelinating processes, such as transverse myelitis, optic neuritis and neuromyelitis optica.

An uncommon illness with a rare presentation: neurosurgical management of ADEM with tumefactive demyelination in children

PURPOSE

This study determined the statewide incidence and prevalence of acute disseminated encephalomyelitis (ADEM) and examined the course of three pediatric patients treated for tumefactive demyelination (TD) at the Blair E. Batson Children's Hospital.

METHODS

Analyses of ICD-9-CM code hospital records and clinical database were conducted.

RESULTS

From 2001 through 2007 the incidence in pediatric patients under 20 years was 0.4/100,000/year, with a prevalence of 8.6/100,000 during 2008. Three patients presented with TD. Case 1 had a 3-week history of ataxia and diplopia; case 2 presented with a sudden onset of coma, while the third child had a 4-month history of increasing lethargy and clumsiness in all extremities. Cerebrospinal fluid examinations were nondiagnostic. MRI examinations revealed asymmetric T2/fluid-attenuated inversion recovery hyperintensity within the pons (case 1), a large heterogenously enhancing temporal lobe mass, with extensive edema (case 2), and multiple small brain lesions with occasional ring enhancement (case 3). In case 1, intralesional MR spectroscopy demonstrated changes consistent with ADEM. Case 2 required intracranial monitoring, and medical treatment to control elevated ICP. Cases 2 and 3 underwent cortical biopsies that revealed ADEM. All three patients improved with corticosteroid therapy. At a minimum of 15 months follow-up, cases 1 and 2 showed resolution of deficits and MRI lesions, while the third patient demonstrated additional MRI lesions and increasing paraparesis.

CONCLUSIONS

These cases demonstrate that appropriate neuroradiological evaluation, treatment of acutely elevated ICP, and brain biopsy can play critical roles in the management of children with undiagnosed ADEM and TD.

Neurological manifestations of antiphospholipid syndrome

BACKGROUND

Neurologic disorders are among the most common and important clinical manifestations associated with the antiphospholipid syndrome (APS). It is characterized by diverse neurological manifestations. These include stroke, transient ischaemic attack, Sneddon's syndrome, convulsions/epilepsy, dementia, cognitive deficits, headaches/migraine, chorea, multiple sclerosis-like, transverse myelitis, ocular symptoms and Guillain-Barré syndrome.

MATERIAL AND METHODS

We review the latest data about neurologic disorders and APS.

RESULTS

In patients under 45 years of age, 20% of strokes are potentially associated with APS. Our study group recently reported a correlation between primary APS and peripheral neuropathy. Only one study investigated the occurrence of peripheral neuropathy in patients diagnosed with PAPS through electrophysiological study and showed alterations in 35% of patients. The mechanism of nervous system involvement in APS is considered to be primarily thrombotic. However, other mechanisms have been described, such as antiphospholipid antibodies that bind to the neural tissue, deregulating their functions and having an immediate pathogenic effect.

CONCLUSIONS

This review summarizes the latest data regarding the clinical aspects, radiological and therapeutic of major neurologic manifestations associated with antiphospholipid antibodies.

MRI characteristics of patients with antiphospholipid syndrome and multiple sclerosis

MRI findings of primary anti-phospholipid antibody syndrome (PAPLS) are difficult to distinguish from those of multiple sclerosis (MS). Only a few previous studies have compared conventional and non-conventional MRI findings in MS and PAPLS patients. In addition, MRI differences between anti-phospholipid antibody (APLA) positive (+) and APLA negative (-) MS patients have not been reported. Therefore, the aim of this study was to investigate the differences in MRI measures among patients with PAPLS, MS and normal control (NC) subjects. We also explored non-conventional MRI measures in APLA+ and APLA- MS patients. Forty-nine (49) consecutive MS patients among whom 39 had relapsing-remitting (RR) and 10 secondary-progressive (SP) disease course, 30 patients with PAPLS and 49 NC were enrolled. Twenty-eight (28) MS patients were APLA+. MRI measures of T1- and T2-lesion volumes (LV) and brain atrophy, including fractions of whole brain (BPF), gray matter (GMF) and white matter (WMF), were evaluated. The magnetization transfer ratio (MTR) of T2- and T1-LVs and different normal-appearing brain tissue (NABT) compartments as well as diffusion-weighted imaging of whole brain mean parenchyma diffusivity (MPD) were obtained. MS patients differed significantly from NC in all MRI measures. PAPLS patients differed from NC in their T2-LV, in MTR measures and in MPD. When MS patients were compared to PAPLS patients, they showed significantly higher T2- and T1-LVs and T2-LV MTR, lower BPF and GMF and higher MPD. APLA+ RR and SPMS (all APLA+) patients showed significantly higher T2-LV, lower GMF, lower normal-appearing gray matter MTR and higher MPD when compared to APLA- patients. The results indicate that brain abnormalities can be detected in PAPLS patients with non-conventional MRI. MRI reveals more profound injury in patients with MS versus PAPLS. APLA mediates heterogeneous cerebral pathology that remains to be further investigated.

Clinical and MRI correlates of autoreactive antibodies in multiple sclerosis patients

BACKGROUND

Autoreactive antibodies (ARAB) occur more frequently in patients with multiple sclerosis (MS) than in general population and the presence of these antibodies often causes uncertainty regarding the disease course, response to therapy and the diagnosis of MS.

METHODS

Retrospective analyses of the ARAB, clinical and MRI data of a consecutive patient cohort of MS and clinically isolated syndrome (CIS) patients were conducted. The patients were evaluated for an extensive panel that included various subtypes of antiphospholipid antibody (APLA) including anti-phosphatidylethanolamine (APE), anti-phosphatidylserine (APS), anti-beta-2-glycoprotein-1 (ABGP), anti-cardiolipin (ACA), and several other ARAB such as antinuclear antibody (ANA), anti-neutrophilic cytoplasmic antibodies (ANCA), anti-thyroid peroxidase antibodies (ATA), anti-SS-A, and anti-SS-B antibodies. Quantitative MRI analysis was performed in a subgroup of MS patients measuring T2-lesion volume (LV), T1 black hole LV and brain parenchymal fraction (BPF).

RESULTS

A total of 137 patients (mean age 44.7, 84% female) with either MS (n=111; age: mean 46.5+/-S.D. 10.3 years; disease duration: mean 13.0+/-S.D. 10.4 years; EDSS: mean 3.2+/-S.D. 1.9) or CIS (n=26; age: mean 37.7+/-S.D. 7.8 years; disease duration: mean 1.3+/-S.D. 1.1 years; EDSS: mean 1.0+/-S.D. 0.7) were enrolled. Among MS patients, 82 were RRMS, 26 SPMS, and 3 had PPMS. Seventy-seven (69%) of MS patients showed presence of one or more ARAB. The proportion of MS patients with APLA was 55% (61 patients); IgM subtype was most frequent. Co-occurrence of ACA and APE was more frequent in SPMS as compared to RRMS (15.4% vs. 1.2%, p=0.012). The proportion of CIS patients with ARAB was 75% with IgM subtype being the most frequent. However, the ARAB in majority of CIS patients (9 out of 14, 64%) were transient on repeated testing. In a subgroup of 62 MS patients, quantitative MRI analysis showed significantly higher T2-LV in patients with positive APLA (15.1 ml for APLA positive vs. 6.75 ml for APLA negative) after correcting for the disease duration (p=0.048). The patients with ATA also had significantly higher T2-LV after correction for disease duration (19.0 ml vs.8.5, p=0.044).

CONCLUSIONS

ARAB were present in more than two thirds of MS and CIS patients although most of APLA in CIS were transient. The presence of APLA in MS patients was associated with higher T2-LV.

Cerebral Manifestations in the Antiphospholipid (Hughes) Syndrome

The importance of cerebral disease in patients with the Hughes syndrome is now becoming more widely recognized. The range of neuropsychiatric manifestations of APS is comprehensive, and includes focal symptoms attributable to lesions in a specific area of the brain as well as diffuse or global dysfunction. Patients with APS frequently present with strokes and TIA, but a wide spectrum of other neurologic features-also including non thrombotic neurologic syndromes-has been described in association with the presence of aPL. The recognition of APS has had a profound impact on the understanding and management of the treatment of CNS manifestations associated with connective tissue diseases, in particular, SLE. Many patients with focal neurologic manifestations and aPL, who a few years ago would have received high-dose corticosteroids or immunosuppression, are often successfully treated with anticoagulation. In our opinion, testing for aPL may have a major diagnostic and therapeutic impact not only in patients with autoimmune diseases and neuropsychiatric manifestations, but also in young individuals who develop cerebral ischemia, in those with atypical multiple sclerosis, transverse myelitis, and atypical seizures. We would also recommend testing for aPL for young individuals found with multiple hyperintensity lesions on brain MRI in the absence of other possible causes,especially when under the age of 40 years. It is our practice to anticoagulate patients with aPL suffering from cerebral ischemia with a target INR of 3.0 to prevent recurrences. Low-dose aspirin alone (with occasional exceptions)does not seem helpful to prevent recurrent thrombosis in these patients. Our recommendation, once the patient has had a proven thrombosis associated with aPL, is long-term (possibly life-long) warfarin therapy. Oral anti coagulation carries a risk of hemorrhage, but in our experience the risk of serious bleeding in patients with APS and previous thrombosis treated with oral anticoagulation to a target INR of 3.5 was similar to that in groups of patients treated with lower target ratios. Although a double-blind crossover trial comparing low molecular weight heparin with placebo in patients with aPL and chronic headaches did not show a significant difference in the beneficial effect of low molecular weight heparin versus placebo, in our experience selected patients with aPL and neuropsychiatric manifestations such as seizures, severe cognitive dys-function, and intractable headaches unresponsive to conventional treatment may respond to anticoagulant treatment. The neurologic ramifications of Hughes syndrome are extensive, and it behoves clinicians in all specialties to be aware of this syndrome because treatment with anticoagulation may profoundly change the outlook for these patients.