(msk) connective tissue disorders Flashcards
what is rheumatoid arthritis?
chronic joint inflammation that can result in joint damage
what is the main site of inflammation in rheumatoid arthritis?
synovium
which two autoantibodies are associated with rheumatoid arthritis?
rheumatoid factor (RF)
anti- CCP antibodies (cyclic citrullinated peptides)
what is the key pathological process occurring in rheumatoid arthritis?
synovitis
name the most common spondyloarthropathy
ankylosing spondylitis
what is ankylosing spondylitis?
chronic spinal inflammation that can result in spinal fusion and deformity
what are the sites of pathogenesis in ankylosing spondylitis?
enthesis
joints of the spine
sacroiliac joints
name four seronegative spondyloarthropathies
(all lack RF and anti-CCP)
ankylosing spondylitis
reactive arthritis
psoriatic arthritis
enteropathic synovitis (arthritis assocaited with GI inflammation)
how does the spinal deformity in ankylosing spondylitis present?
loss of lumbar lordosis
increased kyphosis (hunched back)
what is the key pathological process occurring in ankylosing spondylitis?
enthesitis
what is systemic lupus erythematosus?
chronic tissue inflammation in the presence of autoantibodies directed against self antigens
which autoantibodies are most commonly associated with SLE?
antinuclear antibodies
anti-dsDNA antibodies
anti-phosphiolipid antibodies
what are anti-phospholipid antibodies associated with in SLE?
increased risk of arterial and venous thrombosis
thromboembolic events
differentiate between arthralgia and arthritis
arthralgia = joint stiffness
arthritis = joint inflammation which can lead to joint stiffness and swelling
what is the characteristic feature of SLE?
multi-site inflammation affecting mainly the skin, kidney and joints
which phenomenon is commonly seen in connective tissue disorders?
Raynaud’s phenomenon
SLE, scleroderma
what is Raynaud’s phenomenon?
intermittent vasospasm of the vessels supplying the fingers due to exposure to cold
= decreased blood flow to fingers
= blanching of the digits
why do fingers go white in Raynaud’s phenomenon?
= decreased blood flow to fingers
= blanching of the digits
why do fingers go blue in Raynaud’s phenomenon?
cyanosis as static venous blood deoxygenates
why do fingers go red in Raynaud’s phenomenon?
reactive hyperaemia
= blood rushes back to the fingers as arteries dilate
who is affected most commonly by SLE?
female aged between 15-45 years
what are some clinical manifestations of SLE?
skin (malar) rash
photosensitive rash
arthritis
mouth ulcers
Raynaud’s phenomenon
pericardial/pleural effusion
haematological features
(renal, cerebral disease)
why is an antibody panel done after receiving a positive ANA result in SLE?
if ANA is positive the clinical laboratory will perform further tests to determine which type of ANA is causing the symptoms
what are the ESR and CRP levels in SLE?
high ESR but CRP is typically normal unless infection or pericardial/pleural effusion (in which case, it is elevated)
what haematological features arise in SLE?
haemolytic anaemia
lymphopenia
thrombocytopenia
which blood tests are carried out for SLE?
FBC U&E LFTs bone profile ESR CRP
(ANA, autoantibody panel,
which test is carried out to assess for the presence of anti-phospholipid antibody?
lupus anticoagulant and anti-cardiolipin antibodies
why is it important to measure albumin in SLE?
early sign of glomerulonephritis
subsequent to diagnosis, why may there be changes in an SLE patient’s blood tests?
reflects adverse reactions to medication
1) abnormal liver function = transaminitis
2) fall in neutrophil count (neutropenia) = if bone marrow is affected
as SLE progresses, how do anti-dsDNA and C3/C4 levels vary?
vary but as disease worsens, anti-dsDNA increases and C3, C4 levels fall
= serologically active
