systemic lupus erythematous (SLE) Flashcards
what is it?
systemic autoimmune condition where inflammation in organs causes acute illness
what does it involve?
skin, joints, kidneys, blood cells and NS
what are autoimmune causes?
genetic predisposition - HLA genes
hormonal factors - inc. oestrogen
environmental factors - UV light, bacterial/viral infection, some meds
what are risk factors?
women - 20-40
smokers
Afro-Caribbean, Hispanic, American, Asian and Chinese
what type of hypersensitivity reaction is it?
type 3
what happens in type 3 hypersensitivity reactions?
immune system attacks cells and tissues resulting in inflammation and tissue damage, involves formation of immune complexes
what is the pathophysiology?
- loss of immune regulation = inc. defective apoptosis
- necrotic cells release nuclear materials act as auto-antigens
- auto-immunity results from exposure to nuclear and cellular auto-antigens
- B and T cells stimulated and autoantibodies produced
- auto-antigens and autoantibodies form immune complexes that circulate and become deposited n basement membrane (type 3 HS)
- activation of complement which attracts leukocytes which release cytokines
- cytokine release perpetuates inflammation which causes necrosis and scarring
what is clinical presentation of mild, moderate and severe?
mild = simple cutaneous changes
moderate = arthritis, effusions
severe = organ-threatening disease
what are non-specific symptoms?
fever
fatigue
weight loss
what are cutaneous features?
photosensitive rash
non-scarring alopecia
oral/nasal ulcers
raynauds
what is renal systemic involvement?
lupus nephritis
proteinuria >0.5 in 24 hours
what is neurological involvement?
seizures, psychosis psychiatric change (delirium psychosis), headache, cranial nerve disorder
what is serositis involvement?
pleuritis or pericarditis
what is haematological involvement (common)?
leukopenia
lymphadenopathy
thrombocytopenia
haemolytic anaemia
what investigations are used?
autoantibodies
