Systemic lupus erythematosus (SLE) is a chronic, multisystem autoimmune disease characterized by periods of flare and remission. It can affect virtually any organ system, leading to significant morbidity if not diagnosed and managed appropriately.
What is it
Systemic lupus erythematosus is an autoimmune connective tissue disease in which the immune system produces autoantibodies against the body’s own cells and tissues. This immune dysregulation results in widespread inflammation and tissue damage, commonly involving the skin, joints, kidneys, blood cells, nervous system, and cardiovascular system. The disease course is highly variable, ranging from mild to life-threatening.
What causes it
The exact cause of SLE is unknown, but it arises from a complex interaction of genetic susceptibility, hormonal influences, environmental triggers, and immune dysregulation. Genetic factors increase risk, particularly in individuals with certain HLA types. Environmental triggers such as ultraviolet (UV) light exposure, infections, and certain medications can initiate or exacerbate disease. Hormonal factors help explain the higher prevalence in women of reproductive age.
What are the symptoms
SLE presents with a wide range of clinical manifestations. Common symptoms include fatigue, fever, joint pain and swelling, and skin manifestations such as a malar (butterfly) rash and photosensitivity. Oral ulcers, hair loss, and Raynaud phenomenon are frequent. Systemic involvement may include renal disease (lupus nephritis), hematological abnormalities (anemia, leukopenia, thrombocytopenia), neurological symptoms (seizures, psychosis), serositis, and cardiovascular complications. Symptoms often fluctuate, with periods of remission and flare.
How the diagnosis is made
Diagnosis is based on a combination of clinical features and immunological laboratory tests. Blood tests commonly reveal a positive antinuclear antibody (ANA), which is highly sensitive for SLE. More specific autoantibodies include anti–double-stranded DNA (anti-dsDNA) and anti-Smith antibodies. Complement levels are often reduced during active disease. Urinalysis and kidney function tests assess renal involvement. Imaging and biopsy, particularly kidney biopsy, may be required to evaluate organ damage. Classification criteria such as the EULAR/ACR criteria are widely used.
Importance of diagnostic tests
Diagnostic tests are essential to confirm SLE, assess disease activity, identify organ involvement, guide treatment decisions, and monitor response to therapy. Autoantibody profiles provide prognostic information, while laboratory and imaging studies help detect potentially life-threatening complications early.
Importance of early diagnosis
Early diagnosis is critical because organ damage in SLE can be progressive and irreversible if untreated. Prompt recognition allows early initiation of immunosuppressive therapy, reducing disease activity, preventing flares, preserving organ function, and improving long-term survival and quality of life.
Management options
Management of SLE is individualized and depends on disease severity and organ involvement. Hydroxychloroquine is a cornerstone of therapy for most patients. Corticosteroids are used to control flares, while immunosuppressive agents such as azathioprine, mycophenolate mofetil, cyclophosphamide, and biologic therapies are used in moderate to severe disease. Supportive care includes sun protection, cardiovascular risk reduction, vaccinations, and regular monitoring.
Prognosis
The prognosis of SLE has improved significantly with advances in diagnosis and treatment. Many patients achieve good disease control and near-normal life expectancy. However, prognosis depends on disease severity, organ involvement, and treatment adherence, with renal and neurological involvement associated with poorer outcomes.
