Systemic lupus erythematosus

Epidemiology

• much more common in females (F:M = 9:1)
• more common in Afro-Caribbeans^ and Asian communities
• onset is usually 20-40 years
• incidence has risen substantially during the past 50 years (3 fold using American College of Rheumatology criteria)

Pathophysiology

• autoimmune disease: SLE a type 3 hypersensitivity reaction
• associated with HLA B8, DR2, DR3
• thought to be caused by immune system dysregulation leading to immune complex formation
• immune complex deposition can affect any organ including the skin, joints, kidneys and brain

^ It is said the incidence in black Africans is much lower than in black Americans - the reasons for this are unclear