Neuro-Lupus, Sjögren Syndrome & Behçet Disease
Systemic lupus erythematosus (SLE), Sjögren syndrome, and Behçet disease are systemic autoimmune and inflammatory conditions with significant neurologic manifestations. Neuropsychiatric lupus affects an estimated 20% of SLE patients and is associated with increased mortality. Sjögren syndrome preferentially involves the peripheral nervous system but can cause CNS demyelination and encephalitis. Behçet disease, a systemic vasculitis with geographic predilection, produces distinctive parenchymal and nonparenchymal neurologic syndromes. Recognition and accurate classification of the neurologic manifestations of these disorders is essential for guiding appropriate immunotherapy and improving outcomes.
Bottom Line
- Neuropsychiatric SLE: Affects ~20% of SLE patients (conservative estimate); ACR defines 19 neuropsychiatric syndromes (12 CNS, 7 PNS); CNS involvement is associated with increased mortality
- Antiphospholipid syndrome: Occurs in up to 30% of SLE patients; cerebral arteries are the most frequent site of arterial thrombosis; lupus anticoagulant confers greater stroke risk than anticardiolipin antibodies
- Sjögren syndrome: PNS involvement predominates (>75% fulfill neuropathy criteria); sensory neuronopathy is the most recognized nonparaneoplastic etiology; CNS demyelination should be treated based on the neurologic disease (MS or NMOSD)
- Behçet disease: Neurologic involvement occurs 5–10 years after disease onset; parenchymal type (4× more common) preferentially affects the brainstem; the "bagel sign" on axial MRI of the cord is a distinguishing feature
- Hydroxychloroquine: Recommended in ALL patients with SLE regardless of disease severity
- Cyclosporine warning: May increase the risk of parenchymal neurologic Behçet disease and should be avoided
Systemic Lupus Erythematosus (SLE)
Diagnostic Criteria
The 2019 ACR/EULAR classification criteria for SLE require a positive ANA as an entry criterion, followed by weighted clinical and immunologic criteria. A total score of ≥10 across additive domains is required for classification. Notably, delirium, psychosis, and seizure are included as clinical criteria, reflecting the importance of neuropsychiatric manifestations in the diagnosis of SLE.
Key Features of the 2019 ACR/EULAR SLE Criteria
- Entry criterion: Positive ANA (≥1:80 on HEp-2 cells or equivalent)
- Classification threshold: ≥10 points from weighted additive criteria
- Neuropsychiatric criteria included: Delirium, psychosis, seizure
- Clinical domains: Constitutional, hematologic, neuropsychiatric, mucocutaneous, serosal, musculoskeletal, renal
- Immunologic domains: Antiphospholipid antibodies, complement (C3, C4), SLE-specific antibodies (anti-dsDNA, anti-Sm)
Neuropsychiatric SLE: Scope and Classification
Neuropsychiatric symptoms are reported in 12–95% of SLE patients depending on the methodology used, though a conservative estimate suggests approximately 20% have true CNS disease attributable to SLE. Approximately 12% of patients have neuropsychiatric involvement as their presenting manifestation. The ACR has defined 19 neuropsychiatric syndromes associated with SLE, divided into CNS and PNS categories.
| ACR-Defined Neuropsychiatric SLE Syndromes | |
|---|---|
| CNS — Diffuse Psychiatric/Neuropsychological (5) | Acute confusional state (delirium), anxiety disorder, cognitive dysfunction, mood disorder, psychosis |
| CNS — Neurologic Syndromes (7) | Aseptic meningitis, cerebrovascular disease, demyelinating syndrome, headache, movement disorder (chorea), myelopathy, seizure disorder |
| PNS Manifestations (7) | Acute inflammatory demyelinating polyradiculoneuropathy (Guillain-Barré), autonomic neuropathy, mononeuropathy (single/multiplex), myasthenia gravis, cranial neuropathy, plexopathy, polyneuropathy |
CNS Neuropsychiatric SLE and Mortality
- The presence of CNS neuropsychiatric syndromes in SLE is associated with increased overall mortality
- Neuropsychiatric involvement may indicate more severe systemic disease activity
- Prompt recognition and aggressive immunosuppressive treatment are essential
Acute Psychosis in SLE
Acute psychosis occurs in 1.5–2.5% of SLE patients and is one of the most distinctive neuropsychiatric manifestations. The episode is typically monophasic and occurs early in the disease course. There is a male predilection and younger patients are more commonly affected. MRI and CSF studies are often normal, which can make the diagnosis challenging.
Acute Psychosis in SLE: Clinical Features
- Prevalence: 1.5–2.5% of SLE patients
- Course: Typically monophasic
- Timing: Early in disease course, often near diagnosis
- Demographics: Male predilection; younger patients
- MRI/CSF: Often normal
- Important evaluation: Test for NMDA receptor antibodies (NMDA-R encephalitis can mimic or coexist with SLE psychosis)
- Prognosis: Generally good outcomes with appropriate treatment
CNS Demyelination in SLE
CNS demyelination occurs in approximately 4% of SLE patients and encompasses a spectrum of presentations including isolated optic neuritis or myelitis, CNS demyelination not meeting MS criteria, coexisting MS, and neuromyelitis optica spectrum disorder (NMOSD) with or without AQP4-IgG. Myelitis is often the presenting manifestation of SLE and is commonly longitudinally extensive. AQP4-IgG is frequently detected in SLE patients with myelitis.
Demyelination in SLE: Key Principles
- Myelitis: Often the presenting manifestation of SLE; commonly longitudinally extensive transverse myelitis (LETM)
- AQP4-IgG: Frequently detected in SLE patients with myelitis — suggests coexisting NMOSD
- CSF-specific OCBs: Patients without CSF-specific oligoclonal bands are less likely to meet MS criteria on long-term follow-up
- Treatment principle: When patients meet criteria for MS or NMOSD, they should be treated for the neurologic disease (not solely for SLE)
Aseptic Meningitis in SLE
Aseptic meningitis occurs in less than 1% of SLE patients. While rare, it requires careful evaluation to exclude infection, which is a critical concern in immunosuppressed patients. Patients on terminal complement inhibitors (e.g., eculizumab) are at particular risk for meningococcal infection, which must be ruled out urgently.
Chorea in SLE
Chorea occurs in approximately 2% of SLE patients and is often the presenting manifestation or occurs early in the disease course. It is highly associated with antiphospholipid antibodies. The movement disorder is typically monophasic, and approximately 50% of cases are unilateral. There is a female predilection, and younger patients are more commonly affected. Oral contraceptive pills and pregnancy are recognized risk factors. Treatment involves corticosteroids combined with anticoagulation.
Antiphospholipid Syndrome (APS)
Antiphospholipid syndrome occurs in up to 30% of SLE patients but can also occur as a primary condition in isolation. It is a major cause of thrombotic morbidity in SLE and has particular relevance for the neurologist due to its predilection for cerebral arterial and venous thrombosis.
| Feature | Detail |
|---|---|
| Diagnostic criteria | ≥1 thrombotic or obstetric event PLUS positive lupus anticoagulant OR persistent anticardiolipin/anti-β2-glycoprotein I antibodies (confirmed on two occasions ≥12 weeks apart) |
| Most common arterial site | Cerebral arteries (stroke is the most frequent arterial thrombotic event) |
| Highest stroke risk | Lupus anticoagulant confers greater stroke risk than anticardiolipin antibodies alone |
| Triple positivity | Positive lupus anticoagulant + anticardiolipin + anti-β2-glycoprotein I → very high thrombosis risk |
| Catastrophic APS | Rapid multifocal thrombosis affecting ≥3 organ systems (commonly CNS, skin, kidneys); life-threatening emergency |
| Myelopathy in APS | Always test for AQP4-IgG — NMOSD accounts for >50% of cases of myelopathy in APS |
APS: High-Risk Features
- Triple positivity (lupus anticoagulant + anticardiolipin + anti-β2-glycoprotein I) confers very high thrombosis risk
- Catastrophic APS: Rapid multifocal thrombosis in ≥3 organs; requires urgent combined anticoagulation, corticosteroids, plasma exchange, and/or IVIg
- Myelopathy in APS: Test for AQP4-IgG, as NMOSD accounts for >50% of cases
Treatment of Neuropsychiatric SLE
| Treatment | Role in Neuropsychiatric SLE |
|---|---|
| Hydroxychloroquine | Recommended in ALL SLE patients regardless of disease manifestation or severity |
| Corticosteroids | First-line for acute neuropsychiatric manifestations; high-dose IV methylprednisolone for severe disease |
| Mycophenolate mofetil | Maintenance immunosuppression; EULAR-recommended |
| Cyclophosphamide | Severe neuropsychiatric SLE (psychosis, myelitis, severe CNS vasculitis); EULAR-recommended |
| Rituximab | Refractory neuropsychiatric SLE; B-cell depletion therapy; EULAR-recommended |
| Anticoagulation | Required for all thrombotic manifestations (APS-related stroke, venous thrombosis) |
| Belimumab (anti-BAFF) | B cell-activating factor inhibitor; shows NO benefit for neuropsychiatric SLE specifically |
Sjögren Syndrome
Diagnostic Criteria
The 2016 ACR/EULAR classification criteria for Sjögren syndrome require at least one symptom of ocular or oral dryness, plus a score of ≥4 from weighted testing criteria. The classic presentation involves glandular inflammation producing sicca symptoms: dry eyes (keratoconjunctivitis sicca) and dry mouth (xerostomia). Neurologic involvement is common and often underrecognized.
2016 ACR/EULAR Sjögren Syndrome Classification Criteria
- Entry criterion: ≥1 symptom of ocular or oral dryness
- Classification threshold: Score ≥4 from weighted testing criteria
- Weighted items: Labial salivary gland biopsy with focal lymphocytic sialadenitis (score 3), anti-SSA/Ro positive (score 3), ocular staining score ≥5 (score 1), Schirmer test ≤5 mm/5 min (score 1), unstimulated salivary flow ≤0.1 mL/min (score 1)
Peripheral Nervous System Manifestations
PNS involvement is the most common neurologic manifestation of Sjögren syndrome, with more than 75% of affected patients fulfilling criteria for neuropathy. The most clinically significant PNS manifestation is sensory neuronopathy (also called sensory ganglionopathy or dorsal root ganglionopathy), for which Sjögren syndrome is the most commonly recognized nonparaneoplastic etiology.
Sensory Neuronopathy in Sjögren Syndrome
- Pathology: Destruction of dorsal root ganglion neurons (nonlength-dependent)
- Clinical features: Profound sensory loss, sensory ataxia, pseudoathetosis
- Distribution: Asymmetric, nonlength-dependent (upper limbs may be affected before or equally to lower limbs)
- Most commonly recognized nonparaneoplastic etiology of sensory neuronopathy
- Motor function: Preserved (pure sensory syndrome)
CNS Manifestations of Sjögren Syndrome
CNS manifestations are less common than PNS involvement but include clinically important syndromes. Several distinct CNS presentations have been described.
Demyelinating Disease
Sjögren syndrome-associated demyelination can present as optic neuritis, myelitis, MS-like disease, or NMOSD. Patients with SSA/SSB antibodies who also have AQP4-IgG are considered to have coexisting autoimmune syndromes, and treatment should be based on the neurologic disease. This is a critical principle: therapeutic decisions should be dictated by the neurologic disease (MS or NMOSD) regardless of the Sjögren diagnosis, and high-efficacy therapy should not be delayed.
Trigeminal Neuropathy
Trigeminal neuropathy is a commonly reported manifestation of Sjögren syndrome. It presents as isolated sensory deficits in the trigeminal distribution and is notably not neuralgiform pain (distinguishing it from trigeminal neuralgia). It can be unilateral or bilateral and often occurs in association with other neuropathies, including painful sensory neuropathy, autonomic neuropathy, sensory neuronopathy, and multiple cranial neuropathies. Importantly, patients are often diagnosed with Sjögren syndrome after the onset of neuropathy.
Encephalitis
Encephalitis in Sjögren syndrome is characterized by T2 hyperintensities on MRI and the presence of SSA (anti-Ro) antibodies in serum. This presentation generally responds well to immunotherapy.
Cerebellar Ataxia
Progressive cerebellar ataxia with gait dysfunction and dysarthria has been described in Sjögren syndrome. This presentation can mimic degenerative cerebellar ataxia. The absence of sensory dysfunction helps distinguish it from the sensory ataxia of sensory neuronopathy. Cerebellar atrophy may be evident on imaging. Some cases are immunotherapy-responsive, making recognition important.
Cognitive Dysfunction
Deficits in processing speed and attention have been described in Sjögren syndrome. These cognitive changes may be subtle and are not reliably detected by screening instruments such as the Montreal Cognitive Assessment (MoCA).
Meningitis and Vasculitis
Both aseptic meningitis and CNS vasculitis have been described in Sjögren syndrome but are exceedingly uncommon.
| CNS Manifestation | Key Features | Distinguishing Points |
|---|---|---|
| Demyelinating disease | Optic neuritis, myelitis, MS-like, NMOSD | Treat based on neurologic disease; do not delay high-efficacy therapy |
| Trigeminal neuropathy | Sensory deficits (NOT neuralgiform pain); unilateral or bilateral | Often diagnosed with Sjögren after neuropathy onset; associated with other neuropathies |
| Encephalitis | T2 hyperintensities on MRI; SSA (anti-Ro) positive | Good response to immunotherapy |
| Cerebellar ataxia | Progressive gait dysfunction, dysarthria; cerebellar atrophy on imaging | Absence of sensory dysfunction distinguishes from sensory neuronopathy ataxia; may mimic degenerative ataxia |
| Cognitive dysfunction | Processing speed and attention deficits | May not be detected by MoCA |
| Meningitis/vasculitis | Exceedingly uncommon | Rule out infection and other etiologies first |
Treatment of Neurologic Sjögren Syndrome
- Demyelinating disease: Treat as dictated by MS or NMOSD criteria when these are met; high-efficacy therapy should not be delayed based on Sjögren diagnosis alone
- Vasculitis (EULAR task force recommendations): Corticosteroids, plasma exchange, cyclophosphamide, rituximab
- Sensory neuronopathy: Immunotherapy (IVIg, rituximab); response is variable and often incomplete once significant ganglion cell loss has occurred
Behçet Disease
Overview and Diagnostic Features
Behçet disease is a systemic vasculitis affecting blood vessels of all sizes with a distinctive geographic distribution. Prevalence varies dramatically by region, from 14.6/100,000 in the United Kingdom to 420/100,000 in Turkey. HLA-B51 confers the highest genetic risk. Neurologic manifestations are included in the International diagnostic criteria for Behçet disease.
Classic Features of Behçet Disease
- Oral ulcers: Recurrent aphthous ulcers (virtually universal; often the first manifestation)
- Genital ulcers: Painful ulceration of the scrotum, vulva, or vagina
- Skin lesions: Acneiform lesions, folliculitis, erythema nodosum
- Pathergy: Exaggerated skin response to minor trauma (pustule at needle prick site)
- Uveitis: Anterior and/or posterior; can be sight-threatening
- Arthritis: Nonerosive oligoarthritis
- Important history: Ask specifically about oral and genital ulcers, as patients may not volunteer this information
Neurologic Behçet Disease: General Principles
Neurologic Behçet disease typically occurs 5–10 years after the initial systemic manifestations and is 3 times more common in males. Two distinct types of neurologic involvement are recognized — parenchymal and nonparenchymal — which rarely co-occur in the same patient.
Parenchymal Neurologic Behçet Disease
Parenchymal disease is 4 times more common than nonparenchymal disease and involves direct inflammatory involvement of CNS structures. The brainstem is most commonly affected, with lesions extending to the thalamus, internal capsule, and subcortical regions. Longitudinally extensive spinal cord lesions also occur.
Parenchymal Neurologic Behçet Disease
- Frequency: 4× more common than nonparenchymal type
- Most common location: Brainstem; extension to thalamus, internal capsule, subcortical white matter
- Spinal cord: Longitudinally extensive spinal cord lesions (LETM)
- "Bagel sign": Axial MRI of the cord shows a thick hyperintense rim with a central hypointense core — helps differentiate from other causes of LETM
- Presentation: Headache plus focal neurologic signs from the involved areas
- CSF: Neutrophilic predominance acutely → transitions to lymphocytic later (pattern similar to TB meningitis); normal or elevated protein; normal glucose; oligoclonal bands infrequent
- Disease course: After treatment, lesion size decreases with subsequent atrophy
Parenchymal Behçet: Diagnostic Considerations
- Brainstem lesions in parenchymal Behçet can overlap with MOGAD and AQP4-NMOSD brainstem lesions — always test for MOG-IgG and AQP4-IgG
- The acute neutrophilic CSF profile can mimic tuberculous meningitis — infection must be excluded
- The "bagel sign" on axial cord MRI (hyperintense rim, hypointense core) is a distinguishing imaging feature
Nonparenchymal Neurologic Behçet Disease
Nonparenchymal disease results from vascular lesions, most commonly cerebral venous sinus thrombosis (CVST). Patients present with subacute headache and signs of increased intracranial pressure. Hemorrhagic infarcts are uncommon despite the venous thrombosis. When arterial structures are involved, aneurysms are more common than in other vasculopathies.
| Feature | Parenchymal Neuro-Behçet | Nonparenchymal Neuro-Behçet |
|---|---|---|
| Frequency | 4× more common | Less common |
| Mechanism | Direct CNS inflammatory involvement | Secondary to vascular lesions |
| Most common presentation | Brainstem syndrome | Cerebral venous sinus thrombosis |
| MRI findings | Brainstem/thalamic/subcortical T2 lesions; "bagel sign" in cord | MRV: venous sinus thrombosis; hemorrhagic infarcts uncommon |
| CSF | Neutrophilic → lymphocytic; elevated protein; normal glucose | Elevated opening pressure; normal CSF indices |
| Symptoms | Headache + focal signs from involved areas | Subacute headache + signs of increased ICP |
| Arterial involvement | Not typical | Aneurysms more common than in other vasculopathies |
| Co-occurrence | The two types rarely co-occur in the same patient | |
Treatment of Neurologic Behçet Disease
| Agent | Role |
|---|---|
| Corticosteroids | First-line acute treatment for parenchymal and nonparenchymal disease |
| Azathioprine | Maintenance immunosuppression; commonly used |
| Mycophenolate mofetil | Alternative maintenance immunosuppression |
| Methotrexate | Steroid-sparing maintenance agent |
| Infliximab (anti-TNF) | Refractory or severe disease |
| Tocilizumab (anti-IL-6) | Refractory disease |
| Rituximab (anti-CD20) | Refractory disease |
| IVIg | Adjunctive therapy |
| IL-1 inhibitors / Interferon alfa | Severe or drug-resistant cases |
| Anticoagulation | Required for thrombotic manifestations (CVST, arterial thrombosis) |
Cyclosporine and Neurologic Behçet Disease
- Cyclosporine may increase the risk of parenchymal neurologic Behçet disease
- This association has been observed in multiple studies and cyclosporine should be avoided in patients with neurologic Behçet disease
- Alternative immunosuppressive agents should be selected
Comparison of SLE, Sjögren Syndrome, and Behçet Disease
| Feature | Systemic Lupus Erythematosus | Sjögren Syndrome | Behçet Disease |
|---|---|---|---|
| Diagnostic Criteria | 2019 ACR/EULAR: Positive ANA + ≥10 points from weighted clinical/immunologic criteria (includes delirium, psychosis, seizure) | 2016 ACR/EULAR: ≥1 symptom of ocular or oral dryness + score ≥4 from weighted testing criteria | International criteria: recurrent oral ulcers + ≥2 of genital ulcers, eye lesions, skin lesions, pathergy; neurologic manifestations included |
| Common CNS Manifestations | Psychosis, seizures, cognitive dysfunction, cerebrovascular disease (APS), chorea, CNS demyelination (NMOSD/MS-like), aseptic meningitis | Demyelinating disease (ON, myelitis, NMOSD), trigeminal neuropathy, encephalitis, cerebellar ataxia, cognitive dysfunction | Parenchymal: Brainstem syndrome, LETM; Nonparenchymal: Cerebral venous sinus thrombosis, arterial aneurysms |
| Key Serologic Markers | ANA, anti-dsDNA, anti-Sm, antiphospholipid antibodies (lupus anticoagulant, anticardiolipin, anti-β2-glycoprotein I), complement (C3, C4) | SSA (anti-Ro), SSB (anti-La); test AQP4-IgG in patients with demyelination | HLA-B51 (genetic risk); no specific serologic marker; test MOG-IgG and AQP4-IgG to exclude mimics |
| Most Common Neurologic Domain | CNS (neuropsychiatric syndromes; ~20% of patients) | PNS (>75% fulfill neuropathy criteria); sensory neuronopathy most recognized | CNS (parenchymal 4× more common; onset 5–10 years after systemic disease) |
| Treatment Approach | Hydroxychloroquine (all patients) + corticosteroids, mycophenolate, cyclophosphamide, rituximab; anticoagulation for APS; belimumab NOT effective for neuropsychiatric SLE | Treat neurologic disease based on phenotype (MS/NMOSD criteria); corticosteroids, cyclophosphamide, rituximab for vasculitis (EULAR) | Corticosteroids, azathioprine, mycophenolate, methotrexate, infliximab, tocilizumab, rituximab; anticoagulation for thrombosis; AVOID cyclosporine |
References
- McCombe JA. Neurologic manifestations of rheumatologic disorders. Continuum (Minneap Minn). 2024;30(4):1189-1225.
- Bertsias GK, Ioannidis JP, Aringer M, et al. EULAR recommendations for the management of systemic lupus erythematosus. Report of a Task Force of the EULAR Standing Committee for International Clinical Studies Including Therapeutics. Ann Rheum Dis. 2010;69(3):529-535.
- Hatemi G, Christensen R, Bang D, et al. 2018 update of the EULAR recommendations for the management of Behçet's syndrome. Ann Rheum Dis. 2018;77(6):808-818.