NEUROLOGIC COMPLICATIONS OF ANTIPHOSPHOLIPID ANTIBODIES

Insights into the role of neutrophils in neuropsychiatric systemic lupus erythematosus: Current understanding and future directions

Central nervous system (CNS) involvement of systemic lupus erythematosus (SLE), termed neuropsychiatric SLE (NPSLE), is a major and debilitating manifestation of the disease. While patients with SLE mostly complain of common neuropsychological symptoms such headache and mild mood disorders that may not even be technically attributed to SLE, many SLE patients present with life-threatening NPSLE syndromes such as cerebrovascular disease, seizures and psychosis that are equally challenging in terms of early diagnosis and therapy. While we are just beginning to unravel some mysteries behind the immunologic basis of NPSLE, advancements in the mechanistic understanding of the complex pathogenic processes of NPSLE have been emerging through recent murine and human studies. The pathogenic pathways implicated in NPSLE are multifarious and various immune effectors such as cell-mediated inflammation, autoantibodies and cytokines including type I interferons have been found to act in concert with the disruption of the blood-brain barrier (BBB) and other neurovascular interfaces. Beyond antimicrobial functions, neutrophils are emerging as decision-shapers during innate and adaptive immune responses. Activated neutrophils have been recognized to be involved in ischemic and infective processes in the CNS by releasing neutrophil extracellular traps (NETs), matrix metalloproteinase-9 and proinflammatory cytokines. In the context of NPSLE, these mechanisms contribute to BBB disruption, neuroinflammation and externalization of modified proteins on NETs that serve as autoantigens. Neutrophils that sediment within the peripheral blood mononuclear cell fraction after density centrifugation of blood are generally defined as low-density neutrophils (LDNs) or low-density granulocytes. LDNs are a proinflammatory subset of neutrophils that are increased with SLE disease activity and are primed to undergo NETosis and release cytokines such as interferon-α and tumor necrosis factor. This review discusses the immunopathogenesis of NPSLE with a focus on neutrophils as a core mediator of the disease and potential target for translational research in NPSLE.

Neuropsychiatric lupus: new mechanistic insights and future treatment directions

Patients with systemic lupus erythematosus (SLE) frequently show symptoms of central nervous system (CNS) involvement, termed neuropsychiatric SLE (NPSLE). The CNS manifestations of SLE are diverse and have a broad spectrum of severity and prognostic implications. Patients with NPSLE typically present with nonspecific symptoms, such as headache and cognitive impairment, but might also experience devastating features, such as memory loss, seizures and stroke. Some features of NPSLE, in particular those related to coagulopathy, have been characterized and an evidence-based treatment algorithm is available. The cognitive and affective manifestations of NPSLE, however, remain poorly understood. Various immune effectors have been evaluated as contributors to its pathogenesis, including brain-reactive autoantibodies, cytokines and cell-mediated inflammation. Additional brain-intrinsic elements (such as resident microglia, the blood-brain barrier and other neurovascular interfaces) are important facilitators of NPSLE. As yet, however, no unifying model has been found to underlie the pathogenesis of NPSLE, suggesting that this disease has multiple contributors and perhaps several distinct aetiologies. This heterogeneity presents a challenge for clinicians who have traditionally relied on empirical judgement in choosing treatment modalities for patients with NPSLE. Improved understanding of this manifestation of SLE might yield further options for managing this disease.

Antiphospholipid syndrome and vascular ischemic (occlusive) diseases: an overview

Antiphospholipid syndrome (APS) is primarily considered to be an autoimmune pathological condition that is also referred to as "Hughes syndrome". It is characterized by arterial and/or venous thrombosis and pregnancy pathologies in the presence of anticardiolipin antibodies and/or lupus anticoagulant. APS can occur either as a primary disease or secondary to a connective tissue disorder, most frequently systemic lupus erythematosus (SLE). Damage to the nervous system is one of the most prominent clinical constellations of sequelae in APS and includes (i) arterial/ venous thrombotic events, (ii) psychiatric features and (iii) other non- thrombotic neurological syndromes. In this overview we compare the most important vascular ischemic (occlusive) disturbances (VIOD) with neuro-psychiatric symptomatics, together with complete, updated classifications and hypotheses for the etio-pathogenesis of APS with underlying clinical and laboratory criteria for optimal diagnosis and disease management.

Antiphospholipid syndrome and thrombosis

The antiphospholipid syndrome is an autoimmune condition in which venous or arterial thrombosis is a primary clinical feature. The other primary clinical feature is adverse pregnancy outcome, specifically recurrent miscarriage, fetal death, or preterm delivery due to severe preeclampsia or placental insufficiency. The diagnostic autoantibodies for antiphospholipid syndrome are lupus anticoagulant, anticardiolipin, or anti-beta2-glycoprotein I.

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.

Hughes syndrome, the antiphospholipid syndrome: a new chapter in neurology

The importance of cerebral disease in patients with the antiphospholipid (Hughes) syndrome (APS) 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 transient ischemic attacks, but a wide spectrum of other neurologic features, also including nonthrombotic neurological syndromes, has been described in association with the presence of antiphospholipid antibodies. In this review, we attempt to highlight the large variety of the neurological features of APS.

Atypical movement disorders in antiphospholipid syndrome

Movement disorders have only rarely been reported in association with antiphospholipid syndrome (APS). In such cases, chorea is the most common disorder observed, with occasional reports of hemidystonia, Parkinsonism, and hemiballism. We report here on 3 cases of APS (3 women ages 16, 46, and 56 years) who presented with movement disorders, including tics, tremor, myoclonus, and a corticobasal syndrome, never or rarely reported in association with this disease. Mild executive dysfunction was observed in all 3 patients. We also report the successful treatment of two of these patients with mild oral anticoagulation (INR 2-3). Movement disorders in APS seem more clinically heterogeneous than previously thought. Oral anticoagulation should be considered in the treatment of movement disorders associated with APS.

Neurological involvement in patients with rheumatic disease

Patients with multi-system rheumatic conditions may have disease affecting the central and peripheral nervous systems. Early assessment is often helpful in averting the development of serious complications, which in some conditions can be prevented by the prompt institution of treatment. We review the spectrum of neurological disease in patients with a rheumatological diagnosis. The wide variety of associated neurological complications is discussed in the context of specific rheumatic conditions, varying from spinal cord involvement in rheumatoid arthritis, to neuropsychiatric involvement in systemic lupus erythematosus and neurological sequelae in vasculitic disorders. We discuss diagnostic criteria and recommended management options (where available), and describe the role of new tools such as functional brain imaging in the diagnosis and monitoring of disease. We also discuss the potential for development of neurological complications from the use of anti-rheumatic drugs.

Budding, vesiculation and permeabilization of phospholipid membranes—evidence for a feasible physiologic role of β2-glycoprotein I and pathogenic actions of anti-β2-glycoprotein I antibodies

The in vivo physiologic role of beta2-glycoprotein I (beta2GPI) is presumed to be related to its interactions with negatively charged phospholipid membranes. Increased quantities of procoagulant microparticles derived by the vesiculation of blood cells have been detected in patients with antiphospholipid syndrome (APS) frequently associated with antibodies against beta2GPI (anti-beta2GPI). We investigated the influence of beta2GPI and anti-beta2GPI on giant phospholipid vesicles (GPVs). GPVs composed of phosphatidylserine and phosphatidylcholine were formed in an aqueous medium and individually transferred to a compartment containing either beta2GPI, anti-beta2GPI, or beta2GPI along with anti-beta2GPI. Shape changes of a single GPV were observed by a phase contrast microscope. Most GPVs transferred to the solution containing only beta2GPI budded moderately. Upon the transfer of GPVs to the solution containing beta2GPI and anti-beta2GPI either from patient with APS or mouse monoclonal anti-beta2GPI Cof-22, the budding was much more pronounced, generating also daughter vesicles. No such effects were seen when GPV was transferred to the solution containing anti-beta2GPI without beta2GPI. Our results suggest a significant physiologic role of beta2GPI in the budding of phospholipid membranes, which may be explained by the insertion of the C-terminal loop of beta2GPI into membranes, thus increasing the surface of the outer layer of a phospholipid bilayer. Anti-beta2GPI, recognizing domains I to IV of beta2GPI, enhanced the budding and vesiculation of GPVs in the presence of beta2GPI. This might be a novel pathogenic mechanism of anti-beta2GPI, promoting in vivo the expression of proadhesive and procoagulant phospholipid surfaces in APS.

Current debates in antiphospholipid syndrome: the acquired antibody-mediated thrombophilia

Antiphospholipid (APL) syndrome is the most common form of acquired thrombophilia. It can cause significant morbidity and even mortality. The term "APL antibodies" represents a heterogeneous group of antibodies associated with this disorder. Currently no single assay can identify every APL antibody. Clinically relevant APL antibodies are mainly anticardiolipin antibodies (ACA) detected by solid phase enzyme-linked immunosorbent assay (ELISA) and lupus anticoagulants (LA) demonstrated by in vitro coagulation assay. However, there are some other antibodies associated with the APL syndrome (i.e., subgroup APL antibodies). ACAs, LAs, and subgroup APL antibodies represent intersecting, but non-identical, subsets of autoantibodies. Thus, those autoantibodies may coexist or may occur independently. Any organ system and any size of vessel can be affected during the clinical course of the disease. Therefore, the APL syndrome can manifest itself in a wide variety of clinical thrombotic features. Fetal loss and pregnancy morbidity represent a specific challenge. Despite tremendous advances in the understanding of the pathogenesis of APL syndrome during the past decade, the mainstay of management is still anticoagulation. However, there is no general agreement regarding the duration and intensity of anti-coagulant therapy. In this review, we focused on the current dilemmas and their present clarifications in the wide clinicopathologic spectrum of APL syndrome and APL antibody-related distinct pathologic conditions.

Paroxysmal non-kinesigenic dyskinesia in antiphospholipid syndrome

We report on a patient with a mixed movement disorder classifiable as a paroxysmal nonkinesigenic dyskinesia, occurring as the first manifestation of primary antiphospholipid syndrome (PAPS). Possible pathophysiology is discussed based on recent literature, and we stress that PAPS must be considered in movement disorders of a paroxysmal nature.

Neuronal-binding antibodies from patients with antiphospholipid syndrome induce cognitive deficits following intrathecal passive transfer

Antiphospholipid antibodies (aPL) have been suggested to play a role in causing cognitive and behavioral impairments. In the present study we investigated the pathogenic potential of aPL by intracerebro-ventricular (ICV) administration of immunoglobulins (IgG) from patients with antiphospholipid syndrome (APS). IgG, purified from the sera of four APS patients, was tested for binding to normal mouse brain by immunohistological staining. These IgG (7.5 microg) were injected ICV unilaterally to male C3H mice. Mice injected with IgG purified from pooled sera derived from healthy subjects served as controls. The mice were examined neurologically for motor function and coordination, and cognitively in a Morris water maze. The cognitive tests were performed with the experimenter blinded to the treatment. The performance of the mice in four separate experiments was compared by analysis of variance with repeated measures. IgG from one APS patient was found to bind best to neuronal structures in the hippocampus and cerebral cortex. Mice (n = 43) injected with this IgG performed worse in the water maze compared to the controls (n = 45) with significant effects of the aPL IgG on the overall performance of the mice (treatment, P < 0.03), on learning throughout the experiment (treatment x day, P < 0.02) and on short term memory (treatment x day xtrial, P < 0.002). IgG injected from two of the three other patients also bound specifically to mouse brain neurons and produced an impairment in performance of the water maze. These results support the hypothesis that aPL that gain access to the central nervous system may play a direct role in the pathogenesis of neurological manifestations of APS.

Primary antiphospholipid antibody syndrome: neuroradiologic findings in 11 patients

OBJECTIVE

To describe the neuroradiologic findings of primary antiphospholipid antibody syndrome (PAPS).

MATERIALS AND METHODS

During a recent two-year period, abnormally elevated antiphospholipid antibodies were detected in a total of 751 patients. In any cases in which risk factors for stroke were detected-hypertension, diabetes mellitus, hyperlipidemia, smoking, and the presence of SLE or other connective tissue diseases-PAPS was not diagnosed. Neuroradiologic studies were performed in 11 of 32 patients with PAPS. We retrospectively reviewed brain CT (n = 7), MR (n = 8), and cerebral angiography (n = 8) in 11 patients with special attention to the presence of brain parenchymal lesions and cerebral arterial or venous abnormalities.

RESULTS

CT or MR findings of PAPS included nonspecific multiple hyper-intensity foci in deep white matter on T2-weighted images (5/11), a large infarct in the territory of the middle cerebral artery (4/11), diffuse cortical atrophy (2/11), focal hemorrhage (2/11), and dural sinus thrombosis (1/11). Angiographic findings were normal (5/8) or reflected either occlusion of a large cerebral artery (2/8) or dural sinus thrombosis (1/8).

CONCLUSION

Neuroradiologic findings of PAPS are nonspecific but in young or middle-aged adults who show the above mentioned CT or MR findings, and in whom risk factors for stroke are not present, the condition should be suspected.

Induction of antiphospholipid antibodies by immunization with synthetic viral and bacterial peptides

We previously induced pathogenic antibodies against anionic phospholipids (PL) in experimental animals by immunization with lipid-free purified human beta2glycoprotein I (beta2GPI). We hypothesized that antiphospholipid antibodies (aPL) are induced by in vivo binding of foreign beta2GPI to self-PL, thus forming an immunogenic complex against which aPL antibodies are produced. If this hypothesis is true, other PL-binding proteins that are products of ubiquitous viral/bacterial agents may also induce aPL. To test this hypothesis, groups of NIH/Swiss mice were immunized with synthetic peptides of viral and bacterial origin that share structural similarity with the putative PL-binding region of beta2GPI. Compared with the control groups, animals immunized with the peptides produced significantly higher levels of aPL and anti-beta2GPI antibodies. These findings demonstrate that some PL-binding viral and bacterial proteins function like beta2GPI in inducing aPL and anti-beta2GPI production, and are consistent with a role for such viral and bacterial proteins in inducing aPL antibody production in humans.

Primary antiphospholipid syndrome and cerebral atrophy: a rare association?

Neurologic complications are common in patients with antiphospholipid syndrome. In this article, we report the case of a young woman with neurologic disorders, a history of hypertension and transient ischemic attacks, and cerebral atrophy associated with primary antiphospholipid syndrome (PAPS). Magnetic resonance imaging of the brain showed multiple ischemic lesions and remarkable atrophy of frontal and parietal lobes. Cerebral atrophy in patients with PAPS can be considered as a feature of this disease. The case is discussed on the basis of relevant past literature. Although there are few reports on neuroradiologic findings in patients with PAPS, cerebral atrophy has been described. Because PAPS is more frequently recognized today than in the past, this condition should be included in the differential diagnosis of cerebral atrophy, particularly in young patients.

Anti-phospholipid antibodies in patients with multiple sclerosis and MS-like illnesses: MS or APS?

OBJECTIVE

To describe the frequency, clinical, and laboratory features of patients diagnosed with multiple sclerosis (MS) or MS-like illnesses (MSL) among a large, prospectively followed cohort of anti-phospholipid antibody (aPL)-positive patients.

METHODS

Between 1990 and 1995 patients referred to a university-affiliated rheumatology clinic were prospectively evaluated for aPL based on questionnaires designed to detect aPL-related symptoms and/or a family history of aPL-related illnesses. Magnetic resonance imaging (MRI) was performed when significant neurological features were present. A subgroup of all patients diagnosed with MS or MSL was identified and their clinical, laboratory, and imaging findings were reviewed.

RESULTS

Of 322 patients evaluated for aPL-related symptoms or events, 189 (59%) were positive for at least one class of aPL. Twenty-six of 322 patients (8%) carried a diagnosis of MS or MSL, either at the initial evaluation or during the study period. Twenty-three of the 26 individuals (88%) tested positive for aPL, while the remaining 3 (11%) tested repeatedly negative. Eighteen of the 23 patients (78%) had either more than one class of aPL or had multiple positive titers. IgM aCL was noted in 18 of the 23 patients (78%). Oligoclonal bands were noted in five patients. Antinuclear antibodies (ANA) and low complement levels were frequently observed. Blinded MRI readings showed lesions consistent with MS in the majority of cases. Clinically, 7 patients had transverse myelitis (TM), while optic neuritis (ON) was present in 8 patients. Most patients had either occult symptoms of rheumatic disease or contributory family histories. None had a defined underlying connective-tissue disease.

CONCLUSION

A substantial number of aPL-positive patients have a concurrent diagnosis of MS or MSL, frequently presenting with elevated IgM aCL, optic neuritis, and transverse myelitis. The anti-phospholipid syndrome (APS) should be strongly considered as an alternative diagnosis to MS in these patients.

Lessons from experimental APS models

Several animal models for antiphospholipid syndrome (APS) have been reported in the literature. These experimental models have contributed significantly in resolving enigmas in this multisystemic disease. We, and others have previously shown the pathogenicity of anticardiolipin (aCL) antibodies in pregnancy outcome. We have expanded our studies to show the pathogenicity of aCL antibodies in renal dysfunction and neurological and behavioral impairments in animals with experimental APS. Animals immunized with aCL or with the cofactor beta2GPI developed clinical manifestations of APS, including fetal loss, thrombocytopenia and neurological and behavioral dysfunction, along with elevated levels of aPL antibodies. In another animal model, peripheral blood lymphocytes (PBLs) derived from APS patients could initiate APS manifestations with renal dysfunction in SCID mice. A unique in vivo model for thrombus formation was recently established to show the pathogenicity of aPL in thrombosis associated with APS. Histological evaluation of affected tissues derived from animals or from patients with APS have pointed to common mechanisms underlying APS, showing mainly thrombotic changes accompanied by mild inflammatory reaction.

Outcome of pregnancy in three patients with primary antiphospholipid syndrome after stroke

OBJECTIVE

Ischemic stroke is the most common neurological manifestation in patients with antiphospholipid syndrome (APS). Pregnancy in APS patients markedly increases the risk of thrombosis. There is no data on pregnancy outcome in patients with APS with a history of an ischemic stroke. We report our experience with three APS patients with a history of stroke who had successful pregnancies and deliveries.

PATIENTS

Three patients with APS and previous stroke were treated with small doses of aspirin and anticoagulants during pregnancy.

RESULTS

The patients remained free of attacks of cerebral ischemia during their pregnancies and at follow-up periods of 1 to 4 years.

CONCLUSIONS

Successful pregnancy and delivery is possible in APS patients with a history of stroke, treated with low-dose aspirin and anticoagulants. A previous episode of cerebral ischemia should not be considered an absolute contraindication for an APS patient to become pregnant.

Transient global amnesia and transient ischemic attack: a community-based case-control study

OBJECTIVES

Few case-control studies of first-ever transient global amnesia (TGA), transient ischemic attack (TIA) and normal controls have been performed to date. We aimed to assess the prevalence of cerebrovascular risk factors in a well defined population of TGA patients.

MATERIAL AND METHODS

We undertook a retrospective and prospective community-based case-control study of 170 first-ever TGA, 170 first-ever TIA and 170 normal controls.

RESULTS

Age-matched analysis revealed that TGA cases had a significantly lower prevalence of atrial fibrillation and diabetes mellitus than TIA controls. The prevalence of cigarette smoking and diabetes mellitus was significantly higher in normal controls than in TGA cases.

CONCLUSION

Our community-based case-control study showed that atrial fibrillation and diabetes mellitus, two important risk factors for cerebrovascular disease, were significantly more common in the TIA group than in the TGA one. These results make the thromboembolic pathogenesis of TGA unlikely.

Antiphospholipid antibody syndrome in pediatric patients

The antiphospholipid antibody syndrome is characterized by the association between recurrent arterial or venous thrombosis and the presence of circulating antiphospholipid antibodies. Antiphospholipid antibody-related thrombosis seems to constitute a significant proportion of childhood thromboses. About one third of children suffering a thrombotic event have circulating antiphospholipid antibodies, and more than two thirds of children with idiopathic cerebral ischemia meet the criteria for the diagnosis of antiphospholipid antibody syndrome. Because the other risk factors for thrombosis commonly found in adults have no impact on the pediatric patient, the risk for thrombosis and thrombotic recurrences and the optimal anticoagulation therapy may differ from adults.

Incidence of transient global amnesia in the Belluno province, Italy: 1985 through 1995. Results of a community-based study

INTRODUCTION

We sought to determine the incidence rate of all the new cases of first-ever-in-a-lifetime transient global amnesia in the Belluno province, Italy. Only two prospective epidemiological studies on TGA incidence have been performed to date, non in Italy. Our study aimed to provide reliable and comparable information on TGA incidence.

MATERIAL AND METHODS

We undertook a prospective population-based study in the territory of the province of Bulluno, Italy, between June 1, 1992 and December 31, 1995. We also retrospectively reviewed the clinical records of all the patients with a diagnosis of amnesia seen in the hospitals of the study area from January 1, 1985 through May 31, 1992.

RESULTS

During the prospective study period we identified 77 patients who experienced a first-ever TGA. The crude annual incidence rate was 10.4/100,000 (9.35/100,000 for men and 11.37/100,000 for women). After adjustment to the European population, the incidence rate decreased to 8.60/100,000 per year. The crude annual incidence rate during the retrospective study period was 5.81/100,000. The demographic and clinical features of the two groups did not differ one to the other.

CONCLUSIONS

The incidence rate of first-ever TGA registered in the province of Belluno, Italy, was closely similar to that reported in Turku, Finland and confirms that TGA is more common than has been usually proposed. We emphasize the usefulness of prospective, rather than retrospective, epidemiological studies for research on TGA.

Thrombotic syndromes and autoimmune diseases

Maintenance of blood flow involves the dynamic interactions between the endothelium, circulating cellular components, coagulation factors, and factors involved in fibrinolysis. Autoantibodies, inflammatory cytokines and other undefined triggers in a genetically predisposed person may lead to an imbalance in the equilibrium between the various hemostatic pathways resulting in potentially catastrophic thrombotic events. This article reviews the clinical manifestations and treatment of selected, potentially life-threatening thrombotic syndromes that may occur in association with autoimmune diseases. Special mention is made of thrombotic events associated with Behçet's syndrome.

[Antiphospholipid antibodies in 66 patients with cerebral infarction between 15 and 40 years old]

The antiphospholipid antibodies (aPLs) are a heterogeneous group of immunoglobulins that have been related with alterations in blood coagulability in recent years. Patients with elevated titers of these antibodies have a high probability to develop thrombotic events, including cerebral infarct (CI). The tests currently used to detect these antibodies are the lupus anticoagulant and ELISA for anticardiolipin antibodies which have a larger proportion of positivity among young patients with CI. In our study we tested 66 patients with cerebral infarcts whose ages ranged from 15 to 40 years for the presence of lupus anticoagulant and anticardiolipin antibodies. The results showed that eleven (16.65%) patients were positive for aPLs and three (4.55%) of them fulfilled the diagnostic criteria for primary antiphospholipid syndrome. These data point out to the importance of investigating aPLs in young patients with CI and its high prevalence in this group compared with healthy population.

[Cerebral vasculopathy in the primary antiphospholipid antibody syndrome. Report of 2 cases]

The antiphospholipid antibodies are associated with a large number of neurologic syndromes, cerebral infarct (CI) being the most common of them. In these cases the pathogenesis of the CI is poorly understood and remains controversial; however, the existence of a vasculopathy is indubitable. We report the cases of two young patients with CI and diagnosis of primary antiphospholipid syndrome who were submitted to cerebral angiograms, and one of them to necropsy. In one case the angiographic findings were similar to those of vasculitis in intracranial vessels. In the other case we observed obstruction in internal carotid artery at the angiography that looked like thrombosis in situ; at necropsy we found non-atherosclerotic obstruction in coronary arteries. In summary, is the primary lesion vasculitis, thrombosis, or both? These cases illustrate the discussion and demonstrate that vasculitic mechanisms may be involved in the vasculopathy of primary antiphospholipid syndrome even though thrombosis occur more frequently.

Treatment of neurologic complications of antiphospholipid antibody syndrome

Thrombosis associated with antiphospholipid antibodies (aPL) occurs in both venous and the arterial circulation. The most common arterial thrombo-occlusive event is cerebral infarction. We briefly review treatment strategies aimed at patients with cerebrovascular disease and aPL. Besides general treatment issues, we discuss primary prevention and secondary prevention. Most regimens include antithrombotics or immune modulation. Prospective studies (currently underway) are required to better estimate the rate of recurrent thrombo-occlusive events on standardized therapy before one therapy can be recommended over another with reasonable evidence.

Chorea and high antiphospholipid antibodies: probable primary antiphospholipid syndrome

A young man presented with generalized chorea as the first manifestation of probable primary antiphospholipid syndrome. He was well till 3 months before admission when he started to have involuntary, choreiform movements involving all extremities, the head and the bulbar muscles. Apart from these movements his physical examination was otherwise unremarkable. Laboratory investigations revealed mild thrombocytopenia, high partial thromboplastin time (PTT) only partially corrected by the addition of normal plasma, false positive syphilis serology, weakly positive antinuclear antibody and a high level of IgG anticardiolipin antibodies. Brain magnetic resonance imaging (MRI) showed multiple scattered small areas of high signal intensity on T2 weighted image in the area of centrum semiovale bilaterally. The patient was started on aspirin and prednisone with rapid symptomatic improvement. Despite the difficulty in proving the association between chorea and the high antiphospholipid antibodies, chorea appears in this case to be the initial symptom of primary antiphospholipid syndrome and we suggest screening for antiphospholipid antibodies in unexplained cases of chorea.

Anti-neuronal antibodies in antiphospholipid syndrome with central nervous system involvement: the difference from systemic lupus erythematosus

The presence of antineuronal antibodies was compared in 43 patients with primary aPLS and 57 patients with neuropsychiatric SLE. Fifty-eight patients with Guillain-Barré syndrome and 72 normal healthy donors served as control groups. Seventeen patients in the study group had aPLS associated with CNS involvement. Antineuronal antibodies were studied in the sera employing a novel flow cytometric assay. The frequency of antineuronal antibodies in patients with aPLS and CNS involvement was not significantly different from that of patients with aPLS without CNS disease or from that found in the control groups (12%, 19% and 7%, respectively). However, it was significantly different from that found in SLE patients with CNS involvement (60%) (P < 0.001). Our results provide further evidence that unlike CNS-SLE, the major mechanism of CNS involvement in patients with primary aPLS might not be autoantibody (antineuronal) mediated, but rather 'thrombotic' in origin, or due to yet unknown factors.