Some controversies of neuropsychiatric systemic lupus erythematosus

Vasculitis in Juvenile-Onset Systemic Lupus Erythematosus

Juvenile-onset systemic lupus erythematosus (JSLE) is a rare, heterogeneous multisystem autoimmune disease that can affect any organ, and present with diverse clinical and serological manifestations. Vasculitis can be a feature of JSLE. It more commonly presents as cutaneous vasculitis than visceral vasculitis, which can affect the central nervous system, peripheral nervous system, lungs, gut, kidneys, heart, and large vessels. The incidence and prevalence of vasculitis in JSLE has not been well described to date. Symptoms of vasculitis can be non-specific and overlap with other features of JSLE, requiring careful consideration for the diagnosis to be achieved and promptly treated. Biopsies are often required to make a definitive diagnosis and differentiate JSLE related vasculitis from other manifestations of JSLE, vasculopathies, and JSLE related antiphospholipid syndrome. Visceral vasculitis can be life threatening, and its presence at the time of JSLE diagnosis is associated with permanent organ damage, which further highlights the importance of prompt recognition and treatment. This review will focus on the presentation, diagnosis, management and outcomes of vasculitis in JSLE, highlighting gaps in the current evidence base.

Microembolic Signals in Patients with Systemic Lupus Erythematosus

Introduction:

Central nervous system (CNS) involvement is a common and less understood aspect of systemic lupus erythematosus (SLE). Microembolic signals (MES) have been reported in SLE. We conducted a prospective study to evaluate the frequency of MES among patients with CNS involvement and those without. The main aim of the study is to clarify the pathophysiology of the CNS involvement in SLE.

Methods and Materials:

Sixty eight patients with a diagnosis of SLE (60 females, 8 males) participated in the study. Both middle cerebral arteries were monitored using transcranial Doppler for 60 min to detect MES. All cases underwent neurology and psychiatry assessments.

Results:

MES were detected in 7/68 patients (10.3%) with the mean number of 3.5 per hour. MES were significantly higher in patients with CNS involvement (6/24, 25%) than those without (1/44, 2.2%) (P=0.006). SLE disease activity index, duration of disease, plaque formation, intima-media thickness, and antiphospholipid antibodies were not associated with MES. MES were more frequent in patients receiving Aspirin and/or Warfarin (p=0.02).

Conclusions:

MES may be a predictor for CNS involvement in SLE patients at risk for neuropsychiatric syndromes. Cerebral embolism may be implicated in the pathophysiology of neuropsychiatric SLE.

Detection of cerebral embolic signals in patients with systemic lupus erythematosus

BACKGROUND

Involvement of the CNS in systemic lupus erythematosus (SLE) is caused by several pathogenic mechanisms including cerebral embolism.

AIM

To measure the frequency of microembolic signals (MES) by using transcranial Doppler (TCD) ultrasound and to assess their association with cerebral infarction, neuropsychological dysfunction, and biochemical, sonographic and clinical variables in an unselected group of patients with SLE.

METHODS

A 1-h TCD recording from the middle cerebral artery was carried out in 55 patients with SLE having a mean age of 46 (SD 13) years. MRI of the brain, carotid artery ultrasonography with intima-media thickness and atherosclerotic plaque assessments were carried out in addition to a broad biochemical and clinical assessment. All patients underwent a neuropsychological assessment.

RESULTS

Of the 55 patients, MES were detected in 5 (9%) and cerebral infarcts were found in 9 (18%). A significant association was found between MES and cerebral infarcts and considerably more neuropsychological deficits were found in MES-positive patients compared with the negative group. MES were not associated with other clinical, sonographic and biochemical factors believed to be associated with cerebral embolism.

CONCLUSIONS

Cerebral embolism may be one of the important mechanisms responsible for the high prevalence of cerebrovascular events and the neuropsychological deficits observed in patients with SLE. Although the number of MES-positive patients was small, the lack of a significant association between MES and other known risk factors for MES suggests a complex pathogenesis for the embolisation in these patients.

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.

Systemic lupus erythematosus vasculitis: A current therapeutic overview

The development of systemic lupus erythematosus (SLE) vasculitis is of prognostic value. The earlier the vasculitis is treated, the better the prognosis for SLE. Cutaneous vasculitis is common in SLE, whereas visceral vasculitis is rare. Skin SLE vasculitis is successfully treated with antimalarials, but its discontinuation may result in an SLE flare even among patients in remission. When visceral SLE vasculitis is encountered, or when a disease state is perceived to be life-threatening, a more aggressive therapy is warranted. A combination of medications, plasmapheresis, and intravenous immunoglobulin treatment, along with high-dose steroids and cytotoxic drugs, are typically employed in the treatment of severe SLE vasculitis. Finally, patients with SLE vasculitis may benefit from a number of autoimmune disease therapies currently under investigation, such as switching cytokine responses from Th1 to Th2, and the manipulation of toll-like receptors, chemokines, and FcR receptors. Specific B-cell therapies (eg, anti-Blys, B-cell depletion) may also emerge as potential treatments for SLE vasculitis.

The blood-brain barrier in systemic lupus erythematosus

Central nervous system (CNS) involvement may occur in 20-70% of systemic lupus erythematosus (SLE) patients where neurological symptoms are overt; this is termed neuropsychiatric lupus or NPSLE. This review summarizes evidence that damage to the brain endothelium forming the blood-brain barrier (BBB) is a contributory factor in NPSLE. The normal CNS is protected by blood-tissue barriers at three sites, the brain endothelium (BBB), the choroid plexus epithelium (blood-CSF barrier) and the arachnoid epithelium. The tight junctions of the barrier layers severely restrict entry of plasma constituents including proteins, so that the CSF and brain interstitial fluid contain low levels of protein. Methods for diagnosing BBB damage include imaging (CT, MRI) using contrast agents, and analysing protein content and profiles of CSF Changes in the albumin quotient Qalbumin show evidence for barrier damage, while changes in the immunoglobulin (Ig) index can indicate intrathecal antibody production. However, BBB damage may be transient, and hence undetected or underestimated. Few mechanistic studies exist, but the two main candidate mechanisms for BBB damage are microthrombi in cerebral vessels leading to ischaemia, and immune-mediated attack and activation of the endothelium leading to local cytokine production. Both can result in barrier breakdown. Neurological syndromes could then be secondary to damage to the BBB. The implications for treatment of NPSLE are discussed.