15. Immune System - Autoimmune Disorders Flashcards
What are autoimmune disorders?
Conditions associated with an immune response against the body’s own tissues
What is autoimmunity?
A breakdown of the mechanisms responsible for self-tolerance
What are formed to fight self-antigens?
Autoantibodies
Cytotoxic T-cells
What does the antibody-antigen reaction lead to?
Complement activation
Inflammation
Tissue damage
Which genetic markers are linked with autoimmune diseases?
HLA: B27, DQ2, DR2, DR3, DR4
What digestive tract situation is linked with autoimmune diseases?
Increased intestinal tract permeability (leaky gut)
Systemic Lupus Erythematosus (SLE): definition
Chronic, inflammatory, autoimmune, multi-system disorder in which antibodies are formed against nuclear antigens
Systemic Lupus Erythematosus (SLE): pathophysiology
B-cell activation increasing IgG levels against components of cell nuclei
Inability to remove immune complexes from tissue
Complement is activated causing inflammation
Impaired T-cell regulation
Systemic Lupus Erythematosus (SLE): aetiology
- Multifactorial interaction between various genetic and environmental factors
- Higher oestrogen levels
- Low vitamin D levels
- Chronic bacterial infections common pre-diagnosis
- Viral infections e.g. EBV
- Smoking, silica dust (from concrete)
- Oral contraceptive pill, HRT, stress, UV light, pesticides can all cause flare-ups
Systemic Lupus Erythematosus (SLE): signs and symptoms
Fever, malaise
Butterfly rash, photosensitivity, vasculitis (pain in fingertips), Raynaud’s syndrome (arteries in spasm)
Joint pain - peripheral (sym/asym) - hands, knees, elbows
Pleurisy, pericarditis, hypertension
Nephritis (nephrotic syndrome)
Lymphadenopathy, splenomegaly, anaemia, leukopenia
Systemic Lupus Erythematosus (SLE): diagnostics
Blood tests: anti-nuclear antibodies (ANAs), anaemia, elevated ESR and complement, anti-phospholipid antibodies
Systemic Lupus Erythematosus (SLE): allopathic treatment
Immunosuppressants
Corticosteroids
Sunscreen*
NSAIDs
*This has a consquence for Vit D deficiency
Rheumatoid Arthritis: definition
Autoimmune, chronic, systemic inflammation of the synovium
Potentially affects all organs (except brain)
Rheumatoid Arthritis: pathophysiology
RF (present in around 80% of sufferers) is an auto-antibody which is directed against a portion of IgG
Resultant immune complexes activate complement proteins leading to inflammation
Rheumatoid Arthritis: aetiology
Genetic markers - HLA-DR4 and DR1
Infectious agents e.g. rubella, EBV
Abnormal intestinal permeability, small intestinal bacterial overgrowth (SIBO)
Smoking