← Diagnosis and Management Guides
SLE Flare
Key considerations: Lupus nephritis, Lupus cerebritis, Catastrophic APS
Cannot miss
- Lupus nephritis
- Lupus cerebritis
- Catastrophic APS
- Myocarditis
Likely diagnoses
- SLE flare (skin, joints)
- Drug-induced lupus
- Infection mimicking flare
- Fibromyalgia overlap
Red flags
- Renal involvement (proteinuria, rising creatinine)
- CNS involvement (seizures, psychosis)
- Severe cytopenias
- Serositis
Workup
- history: Medication compliance, sun exposure, infection symptoms, new medications; exam: Malar rash, oral ulcers, joint swelling, serositis, skin lesions; labs: CBC, BMP, ESR, CRP, complement levels (C3/C4), anti-dsDNA, urinalysis with micro, urine protein/creatinine ratio; imaging: CXR if pleuritis/pericarditis, renal ultrasound if nephritis; bedside: Urinalysis for proteinuria, hematuria
Management
- immediate: Severe flare: IV methylprednisolone pulse (1g/day x3 days); Lupus nephritis: steroids + immunosuppressive (mycophenolate or cyclophosphamide); general: Moderate flare: prednisone 0.5-1mg/kg/day; Maintain hydroxychloroquine (reduces flares and mortality); Sun protection
Disposition
- admit: Severe renal, CNS, cardiac, or hematologic involvement; discharge: Mild-moderate flare with rheumatology follow-up within 1-2 weeks; consults: Rheumatology, nephrology if renal involvement
Clinical pearls
- Low complement (C3/C4) + high anti-dsDNA = active lupus nephritis — check both at every visit
- Hydroxychloroquine reduces mortality in SLE and should NEVER be discontinued
- Infection is the top killer in SLE — always rule out infection before treating a flare with immunosuppression
Source and review
- ACR/EULAR SLE Guidelines 2019. Last reviewed: 2024-11-01