Should You Get Tested for Lupus if a Relative Has Been Diagnosed?
Yes, you should discuss screening with your physician, particularly if you have any symptoms suggestive of lupus, as having a first-degree relative with SLE significantly increases your risk—siblings have a 24-fold increased risk and offspring have a 14-fold increased risk compared to the general population. 1
Understanding Your Familial Risk
The genetic component of lupus is substantial but not deterministic:
- First-degree relatives (parents, siblings, children) of patients with SLE face markedly elevated risks: siblings have an RR of 23.68, offspring have an RR of 14.42, and parents have an RR of 11.44 1
- Twins show the highest risk with an RR of 315.94, though this remains far below 100%, indicating that genetics alone do not cause lupus 1
- The heritability of SLE is estimated at 43.9%, with shared environmental factors accounting for 25.8% and non-shared environmental factors 30.3% of disease susceptibility 1
- Even spouses without genetic similarity show a modestly increased risk (RR 4.44), highlighting the role of shared environmental exposures 1
When Testing Is Warranted
Routine screening of asymptomatic relatives is not recommended by current guidelines, as the available evidence focuses on monitoring patients already diagnosed with SLE rather than screening at-risk family members. 2 However, you should pursue evaluation if you develop:
Red Flag Symptoms Requiring Evaluation:
- Mucocutaneous manifestations: Malar (butterfly) rash, discoid lesions, photosensitivity, oral ulcers 3, 4
- Musculoskeletal symptoms: Joint pain, swelling, and morning stiffness affecting multiple joints 3
- Constitutional symptoms: Unexplained fever, profound fatigue, unintentional weight loss 5, 6
- Renal symptoms: Foamy urine, hematuria, edema, changes in urinary frequency 4
- Neuropsychiatric manifestations: Seizures, severe headaches, cognitive dysfunction, mood disorders 3, 4
- Hematologic abnormalities: Easy bruising, recurrent infections, unexplained anemia 7
- Serositis: Pleuritic chest pain, pericardial pain 3
Initial Evaluation Approach
If you develop concerning symptoms, your physician should order:
- ANA (antinuclear antibody) testing as the initial screening test—while not specific for SLE, it is highly sensitive 8, 7
- Complete blood count to assess for cytopenias (low blood cell counts) 7
- Urinalysis to screen for proteinuria and hematuria indicative of kidney involvement 3, 7
- Anti-dsDNA and anti-Smith antibodies if ANA is positive, as these are highly specific for SLE 3, 8
- Complement levels (C3, C4) which are typically low in active SLE 3, 7
Additional Autoimmune Disease Risks
Having a first-degree relative with SLE also increases your risk for other autoimmune conditions:
- Primary Sjögren syndrome (RR 5.87) 1
- Systemic sclerosis (RR 5.40) 1
- Rheumatoid arthritis (RR 2.66) 1
- Type 1 diabetes (RR 1.68) 1
- Myasthenia gravis (RR 2.95) 1
Important Caveats
- Most relatives of SLE patients will never develop the disease, despite increased relative risk—the absolute risk remains low 1
- Early recognition improves outcomes by allowing prompt treatment and preventing aggressive manifestations affecting kidneys, cardiovascular system, and reducing septic complications 5
- Women of childbearing age with a family history should be particularly vigilant, as approximately 90% of SLE patients are female 7
- If you develop lupus, approximately 40% of patients develop lupus nephritis, and 10% of those progress to end-stage kidney disease within 10 years, making early detection crucial 7
Practical Recommendation
Schedule a discussion with your primary care physician or a rheumatologist to review your family history and any symptoms you may be experiencing. Rather than routine screening, maintain heightened awareness of potential symptoms and seek prompt evaluation if they develop. This approach balances the increased familial risk against the reality that most relatives remain unaffected while ensuring timely diagnosis if disease does occur.