Synopsis
Recognise the multisystem patterns of systemic lupus erythematosus, measure activity and accumulated damage separately, screen organs proactively, and select proportionate treatment with infection and reproductive safety built into every decision.
- Suspect SLE when inflammatory joint disease, photosensitive or subacute cutaneous rash, oral or nasal ulcers, alopecia, serositis, cytopenia, renal abnormality or neurological disease occur in a coherent multisystem pattern.
- ANA is a sensitive entry test but is not specific and must not be used as a population screen for non-specific fatigue or pain; a negative result makes ordinary SLE less likely but does not replace specialist judgement.
- When the phenotype supports lupus, define anti-dsDNA, anti-Sm, C3 and C4, FBC, renal and liver function, urinalysis and quantitative protein, and test antiphospholipid, anti-Ro and anti-La antibodies for their distinct consequences.
Key red flags
Fever with hypotension, neutropenia, immunosuppression or a focal source requires immediate sepsis assessment even when lupus activity is also plausible.
Hypertension, proteinuria, dysmorphic haematuria, casts or creatinine change may be the only evidence of nephritis and requires urgent combined review.
Investigation priorities
Support diagnostic assessment when the clinical pre-test probability is meaningful.
Management branches
Multisystem inflammatory features raise a credible suspicion of systemic lupus erythematosus.
- Document chronology, objective skin and joint findings, serosal, neurological, renal, obstetric and thrombotic history, medicines, infections and family history.
- Request ANA with FBC, renal and liver profile, ESR or CRP, blood pressure and urine assessment; add specific antibodies and complements when the phenotype remains compatible.
SLE is confirmed and no contraindication prevents antimalarial treatment.