Systemic Lupus Erythematosus (Pediatric)

Definition

Pediatric systemic lupus erythematosus (pSLE) is a chronic, multisystem autoimmune disease characterized by the production of autoantibodies and immune complex deposition, leading to inflammation and tissue damage in various organs.

Epidemiology

• Accounts for 10–20% of all SLE cases, with onset before 18 years
• More common in females (female:male ratio ~4:1 in children)
• Higher prevalence in African American, Hispanic, and Asian populations
• Peak onset around 12–15 years of age
• Incidence estimated at 0.3–0.9 per 100,000 children per year

Etiology

• Exact cause unknown; multifactorial with genetic, hormonal, and environmental triggers
• Genetic predisposition: HLA-DR2, HLA-DR3 alleles, complement deficiencies
• Environmental triggers: UV exposure, infections, medications
• Hormonal influences: estrogen may exacerbate disease
• Immune dysregulation leading to autoantibody production

Pathophysiology

• Loss of self-tolerance leading to autoantibody formation (ANA, anti-dsDNA, anti-Smith)
• Immune complex deposition in tissues causes inflammation and organ damage
• Complement activation contributes to tissue injury
• Cytokine dysregulation amplifies inflammatory response
• Multi-organ involvement: skin, kidneys, joints, CNS, hematologic system
• Chronic relapsing-remitting course influenced by genetic and environmental factors