Flashcards in 8 Autoimmune diseases Deck (17)
Differentiate between autoimmunity and autoimmune disease.
Autoimmunity is a theoretical concept of a break down of self tolerance.
Autoimmune disease is a clinical entity with environmental and genetic factors.
What is central tolerance and where does it occur?
Destruction of self-recognising antigens. Occurs in the thymus.
What are the causative associations of autoimmune disease?
Age - older>younger.
Environmental: tissue damage, smoking, infection.
How does autoimmunity cause clinical disease?
B cells are directly cytotoxic, activate complement and interfere with function.
T cells are directly cytotoxic and produce inflammatory cytokines.
Inflammation and end organ damage.
Differentiate between organ specific and systemic autoimmune diseases.
Affects single organ - thyroid is typical.
Affects several organs - connective tissue diseases air typical.
Describe hashimotos thyroiditis.
Destruction of thyroid follicles.
Autoantibodies to thyroglobulin and thyroid peroxidase. Leads to hypothyroidism.
Describe grave's diseases.
Inappropriate stimulation of thyroid gland by ant-TSH-autoantibody. Leads to hyperthyroidism.
What is the cause of myasthenia graves and how is it's weakness circadian?
Autoantibodies to AChR preventing transmission. Gets worse throughout the day.
What is pernicious anaemia?
Failure of vitamin B12 absorption due to autoantibodies to intrinsic factor. Leads to microcytic anaemia.
Name four systemic autoimmune diseases.
Systemic lupus erythematosus.
What is auto inflammation?
spontaneous attacks of systemic inflammation without infection or presence of autoantibodies/autoreactive T cell.
What causes systemic lupus erythematous?
Defects in apoptosis lead to anti-nuclear antibody creation.
What are ANCA antibodies and what do they lead to?
Anti-Neutrophil Cytoplasmic Antibodies. Lead to widespread neutrophil activation (granulomas - lung) and inflammation around the blood vessels (polyangitis-skin, kidney, lung, gut).
What are the 3 forms of ANCA vasculitis?
Granulomatosis with Polyangitis.
Eosinophilic Granulomatous with Polyangitis.
What is Raynauds phenomenon? Significance of bimodal distribution?
Young: harmless, ANA -ve.
Odler: ANA +ve, associated with scleroderma and SLE.
What is scleroderma?
Anti-Nuclear Antibodies lead to ischaemia and fibrosis - Raynauds, skin thickening and tightening in fingers, face, lungs, gut, kidneys.