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Management of Systemic Lupus Erythematosus

test and ELISA tests for anticardiolipin antibodies (aCL) and anti-beta-
2-glycoprotein 1 (anti-β2GP1). In SLE, 30 - 40% of patients are positive
for aPL. 27, level II-2; 28, level III
The presence of aPL is incorporated as an immunologic domain for
classification of SLE. The aPL includes: 23; 29, level III
 aCL antibodies (immunoglobulin A [IgA], immunoglobulin G
[IgG] or immunoglobulin M [IgM]) at medium or high titre (>40 A
phospholipids [APL], G phospholipids [GPL] or M phospholipids
[MPL] units, or >99 percentile)
th
 anti-β2GP1 (IgA, IgG or IgM)
 LA
In antiphospholipid syndrome (APS), two tests with a minimum interval
of 12 weeks are necessary in order to exclude short-term IgM antibodies
following a vascular event or an infection. 30, level III

• Complements
Complement activation is a key event in the pathogenesis of tissue
inflammation and injury in SLE patients where decreased levels of
C3 and C4 are detected along with disease activity. However, serum
complement levels can be affected by various physiological conditions
e.g. infections, traumatic damage or immunosuppressants, and not
only in patients with autoimmune diseases but healthy individuals. 31,
level III; 32, level III

Apart from above, further investigations will depend on the symptoms
of SLE that are present. 33, level III

Recommendation 1
• The following tests should be done to assist in the diagnosis of
systemic lupus erythematosus (SLE):
 full blood count with differential counts
 renal profile
 liver function test
 urinalysis
 erythrocyte sedimentation rate with/without C-reactive protein
 antinuclear antibodies and anti-double stranded deoxyribonucleic
acid
 complement 3 and complement 4
• All patients with SLE should be screened for antiphospholipid
antibodies at diagnosis.

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