Systemic Lupus Erythematosus (SLE)
The British Society for Rheumatology guideline for the management of systemic lupus erythematosus in adults. Published: Oct 2017.
Guidelines
Investigation and Diagnosis
Work Up and Diagnosis
| Test | Interpretation | Notes |
|---|---|---|
| Antinuclear antibody (ANA) | Screening test for lupus
Highly sensitive (~95%) but not specific |
-ve ANA makes SLE unlikely, +ve in ~5% healthy adults
Poor diagnostic value alone |
| Anti-dsDNA antibodies | Specific marker for SLE (but less sensitive)
Correlates with disease activity, especially lupus nephritis |
+ve anti-dsDNA makes SLE very likely |
| Anti-Smith (Sm) antibodies | Specific marker for SLE (but less sensitive) | +ve anti-dsDNA makes SLE very likely |
| Complement levels (C3, C4) | Decreased levels in active disease | High negative predictive value for excluding active disease |
| ESR | Elevated in active disease but non-specific | |
| CRP | Usually normal in active disease (or raised modestly) | Elevated CRP suggests infection or inflammation unrelated to lupus |
Note that anti-Ro (SSA), anti-La (SSB), and anti-RNP antibodies can also be +ve in SLE but are less specific as they are also seen in other rheumatological conditions.
The combination of +ve ANA (screening test) and +ve anti-dsDNA or anti-Sm antibodies (confirmatory test) makes SLE very likely.
Further Work Up Post Diagnosis
- All SLE patients should be tested for antiphospholipid antibodies → Screen for secondary APS
- Screen for renal involvement by urinalysis, renal function +/- spot urine albumin:creatinine ratio
Serology in Other Forms of Lupus
The following 2 types of lupus have different serology patterns to SLE (above):
- Drug-induced lupus
- Typical serology is +ve ANA and +ve anti-histone antibodies
- Anti-dsDNA and anti-Sm antibodies are usually -ve
- Cutaneous lupus
- Acute cutaneous lupus erythematosus (ACLE)
- +ve ANA, + anti-dsDNA
- ACLE is frequently associated with active SLE
- Subacute cutaneous lupus erythematosus (SCLE)
- +ve anti-Ro/SSA & anti-La/SSB antibodies (most frequent)
- +ve ANA
- anti-dsDNA may be positive ; but less frequently than ACLE
- Chronic cutaneous lupus erythematosus (most commonly discoid lupus)
- Typically seronegative
- Acute cutaneous lupus erythematosus (ACLE)
Monitoring
Patients with active SLE should be reviewed at least every 1-3 months, with the following assessment:
- Blood pressure
- Urinalysis and renal function
- Blood tests
- Anti-dsDNA antibodies
- Complement levels
- CRP
- FBC and LFT
Management
General / Conservative Management
- Sun protection (advice on sun avoidance and use of high sun protection factor sunscreen)
- Smoking cessation
- Healthy diet
- Regular exercise
Also important to optimise and treat comorbidity, esp. cardiovascular risk management (SLE increases CVD risk)
Pharmacological Management
1st Line
- Hydroxychloroquine – cornerstone drug for ALL patients with SLE
- NSAIDs – to be used for symptom control of mild MSK pain
2nd Line
- Steroids – aim for short courses only with lowest effective dose
- Steroid-sparing immunosuppressive agents
- Methotrexate
- Azathioprine
- Mycophenolate mofetil
- Calcineurin inhibitors (e.g. ciclosporin, tacrolimus)
3rd Line
- High-dose steroids (IV pulses)
- Biologics
- Belimumab
- Rituximab
- IV immunoglobulin and plasmapheresis
Renal Lupus
All SLE patients with suspected renal involvement require a renal biopsy to confirm and classify lupus nephritis.
For class III/IV lupus nephritis:
- High-dose steroid + mycophenolate / cyclophosphamide
Otherwise: steroids +/- azathioprine should be sufficient
Consider rituximab / belimumab in refractory or relapsing cases.