Systemic Lupus Erythematosus Diagnosis and Assessment

Clinical Features and Diagnostic Criteria

The European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR) recommend assessing patients with suspected Systemic Lupus Erythematosus (SLE) for lupus-specific rashes, such as acute cutaneous lupus (malar rash), subacute cutaneous lupus, and chronic cutaneous lupus (discoid lesions) 1
Skin biopsy may be required when clinical morphology is unclear or mimics other conditions, as recommended by the Annals of the Rheumatic Diseases 2, 3
Arthritis, characterized by joint pain, swelling, and morning stiffness affecting multiple joints, should be documented, according to the Annals of the Rheumatic Diseases 4, 5
Serositis, including pleuritic chest pain, pericardial pain, or pleural/pericardial effusions, should be assessed, as recommended by the Annals of the Rheumatic Diseases 4, 5

The Annals of the Rheumatic Diseases suggest measuring anti-dsDNA antibodies, which are highly specific for SLE and correlate with disease activity, particularly renal involvement 4, 5
Antiphospholipid antibodies, including anticardiolipin, anti-β2-glycoprotein I, and lupus anticoagulant, are critical for identifying antiphospholipid syndrome, as recommended by the Annals of the Rheumatic Diseases and Praxis Medical Insights 4, 5, 1
Complement levels, including C3 and C4, should be measured to assess disease activity, with low levels strongly associated with active disease, particularly lupus nephritis, according to the Annals of the Rheumatic Diseases and Praxis Medical Insights 4, 5, 6

Proteinuria, quantified with spot urine protein-to-creatinine ratio, and urine sediment analysis, including red blood cell casts, white blood cell casts, or acanthocytes, should be assessed, as recommended by Praxis Medical Insights 6
Serum creatinine and blood pressure should be measured, with elevated creatinine indicating impaired glomerular filtration, according to Praxis Medical Insights 6
Neuropsychiatric manifestations, including seizures, psychosis, acute confusional state, cognitive dysfunction, and headaches, should be documented, as recommended by the Annals of the Rheumatic Diseases and Praxis Medical Insights 5, 1, 2, 3

In women of childbearing age, obstetric history, including recurrent miscarriages, preeclampsia, intrauterine growth restriction, and stillbirths, should be documented, and antiphospholipid antibodies should be tested, as recommended by Praxis Medical Insights 1
CRP elevation is uncommon in SLE, and if CRP >50 mg/L, superimposed infection should be suspected, according to the Annals of the Rheumatic Diseases 2, 3
Drug-induced lupus should be considered, and medications known to trigger lupus-like syndromes, such as hydralazine, procainamide, and minocycline, should be inquired about, as recommended by Praxis Medical Insights 1