Autoimmune rheumatic diseases Flashcards
What is most rheumatic disease?
most rheumatic disease is multisystematic
What is inflammation of the:
1) joints?
2) lungs?
3) vasculature
4) skin
5) nervous s
6) eyes
7) kidneys
8) muscles?
joints = synovitis
lungs = alveolities / and end stage pulmonary fibrosis, reduced gas exchange and resp failure
veins and arteries = vasculitis inflammation of vessel wall, thrombosis due to impaired flow
Skin = rashes
nervous system = neuropathies or central nervous sytem and cerebral damage
eyes = retinitis
kidneys = nephritis
muscles = myostitis
What is the cause of most rheumatic disease?
most rheumatic disease is autoimmune
What are the components of autoimmune reaction in rheumatic disease and how are they evidenced?
- Autoreactive T cells (can be found at the site of inflammation)
- Autoreactive B/ plasma cells –> autoantibodies (found within blood plasma and at site of inflammation)
- Antibodies detectable at sites of tissue damage
- immunosuppresion treats the disease
What are some examples of organ specific autoimmune diseases?
Brain –> multiple sclerosis
thyroid –> hashimotos thyroiditis, primary myxedema, thyrotoxicosis
muscle –> myasthenia gravis against nAchR
stomach –> pernicious anaemia
Adrenal –> addison’s disease
pancreas –> insulin dependent diabetes mellitus
What are antinuclear antibodies?
When is an ANA test requested?
ANA test identifies the presence of antinuclear antibodies (ANA) in blood.
ANA’s are antibodies directed against components within the cell’s nucleus.
ANA test is requested in cases of suspected autoimmune disease, ANA antibodies is associated with several autoimmune diseases but is most commonly seen in systemic lupus erythematosus (SLE).
When are anti-DNA antibodies most commonly seen?
Anti DNA antibodies most commonly seen in SLE.
Because the ANA test result may be positive in a number of these other diseases, SLE can be tricky to diagnose correctly and additional tests may be used to help. For example, tests to look for antibodies to ENA and dsDNA are used to help interpret the ANA results. All of the results are used in conjunction with patient symptoms and clinical history to find a diagnosis.
What are ENA’s?
When is this test requested?
what can it help distinguish between?
ENA is an antigen directed against one or more proteins within the cell’s nucleus. These proteins are known as extractable as they can be removed from the cell nuclei with saline.
ENA test often requested following a postive ANA test with pts with symptoms of autoimmune disorder.
The 4-test ENA panel is used to help diagnose mixed connective tissue disease (MCTD), systemic lupus erythematosus (SLE), and Sjögren syndrome. The 6-test ENA panel can also help identify scleroderma (systemic sclerosis) and polymyositis/dermatomyositis (inflammatory myopathies).
What antibodies may be found in SLE?
Anti DNA
Anti - Sm
others may be found but these are most common
What anti nuclear antibodies and ENA’s may be found in systemic sclerosis?
Anti-scl70
Anti centromere
both common in systemic sclerosis
What anti nuclear antibodies and ENA’s may be found in sjrogrens syndrome?
Anti-Ro
Anti -La
both common in sjorgren’s syndrome
What anti nuclear antibodies and ENA’s may be found in Anti Jo -1 syndrome?
Anti- JO-1
How is the significance of a positive ANA assessed?
Positive ANA’s are common in healthy people
therefore the significance of a positive ANA needs to be interpreted alongside the pts symptoms and signs
What are 4 common symptoms in patients with autoimmune rheumatic diseases?
1) Secondary Raynaud’s phenomenon (note primary raynauds phenomenon is common and 10% of healthy women have it).
2) Joint pain
3) Rashes
4) Fatigue
What are the three phases of Raynaud’s phenomenon?
After arterial spasm –> Fingers tends to go white, then blue, then hyper red
What is the difference between primary and secondary raynauds?
Primary raynaud’s comes on earlier in life, occurs in 10% of healthy women.
Secondary rayauds comes on later in life and could be a sign there is underlying autoimmune disease
What are some examination findings of sjogrens syndrome?
Reduced tear flow – >Schirmer test (measure how wet strip is within 5 minutes)
dry oral mucosa, dental decay
oral candidiasis
salivary gland swelling
Plus skin involvement –> palpable purpura, often vasculitic rash. Or annular rash (named subacute cutaneous lupus)
What investigations are done in sjogren’s syndrome?
1) FBC –> look for anaemia of chronic disease (low Hb due to inflammatory response reducing blood cell production), sometimes low WBC’s and platelets
2) Raised immunoglobulins due to B cell activation, high IgG
3) High ESR e.g. ESR 80 mm/hr (as a result of high IgG, high viscosity of RBC’s)
4) ANA positive
5) Anti Ro/La positive
6) salivary gland biopsy –> intense blue staining, picking up lymphocytes, called lymphocytic sialadenitis, particular focus score is diagnostic
