Lupus is an autoimmune disease that can affect the skin, joints, blood cells, kidneys and other organs. Symptoms and blood tests need to be interpreted together.
2019 EULAR/ACR classification criteria. Complete this with your clinician using confirmed findings. These are classification criteria, not a self-diagnosis tool.
When to seek care: New chest pain, severe breathlessness, seizures, confusion or markedly reduced urine need urgent medical care. Do not wait for an online score.
Clinical check 1
The entry requirement is ANA ≥1:80 on HEp-2 cells, or an equivalent positive assay confirmed by the clinician. ANA positivity alone does not diagnose lupus.
Clinical check 2
Do not count a feature with a more likely cause, such as infection or a medicine. Findings can have occurred at different times. Count only the highest scoring finding in each domain.
01
Only a documented temperature above the threshold counts; infection and other causes need assessment.
02
Use the single highest category. Autoimmune haemolysis needs evidence of haemolysis and a positive direct antiglobulin test.
03
These are clinician-diagnosed findings. Ordinary forgetfulness or a headache does not qualify.
04
Use clinician-confirmed lupus skin findings; biopsy should support the diagnosis when performed. Select only the highest category.
05
Effusion requires imaging. Acute pericarditis requires at least two: typical pain, rub, characteristic ECG change or a new/worsening effusion.
06
A clinician must confirm inflammation in at least 2 joints, or tenderness in at least 2 joints with morning stiffness lasting at least 30 minutes.
07
Protein excretion >0.5 g/day may use an equivalent urine protein/creatinine ratio. Nephritis classes require a kidney-biopsy report.
08
Lupus anticoagulant, or qualifying anticardiolipin/anti-β2-glycoprotein I antibodies. Anticardiolipin must exceed 40 units or the 99th percentile; a clinician must verify assay criteria.
09
Compare C3 and C4 against the laboratory reference range. Count this domain only once.
10
Anti-Sm or anti-dsDNA counts once, not twice. The anti-dsDNA assay must have demonstrated ≥90% specificity for SLE against relevant disease controls.
Recognise the pattern
Symptoms to discuss
Joint swelling or stiffness, mouth sores, hair loss and sun-sensitive rashes.
Unexplained fever or fatigue; new swelling or urine changes need assessment.
Clinical assessment
Tests and care
Examination, blood count, kidney function, urine testing, ANA and selected antibodies.
Complement levels and organ-specific investigations; a biopsy only when clinically indicated.
Treatment is tailored to the organs involved. Hydroxychloroquine and other medicines may be used with monitoring. Sun protection, follow-up and discussing pregnancy plans with the clinician are helpful.
Classification is not diagnosis. A low score does not rule out disease. Do not arrange every listed test or start, stop or change medicines based on this result; your clinician decides what is needed.