Connective Tissue Disease Flashcards
(36 cards)
What is the pathogenesis of systemic lupus erythematosis (SLE)?
Defective apoptosis increases cell death and releases auto-antigens which form immune complexes. These deposit in small blood vessels, skin, kidneys and other places causing wide range of problems across the body
How does systemic lupus erythematosis (SLE) present?
Wide ranging presentation as it affects multiple body systems.
Fever, fatigue, weight loss
Myalgia, arthalgia
Malar rash, alopecia, photosensitivity
Glomerulonephritis
What may a FBC show in systemic lupus erythematosis (SLE)?
Low RBC, (anaemia)
Low WBC ( leukopenia)
Low platelets (thrombocytopenia)
What markers can be used to assess SLE disease activity?
Complement (low in active disease as it is used up)
Anti-dsDNA (high in active disease)
What autoantibodies are associated with systemic lupus erythematosis (SLE)?
What are the specificities and sensitivities of these auto-antibodies?
Anti-nuclear antibody (ANA)
Anti-double stranded (anti-dsDNA)
ANA
- high sensitivity (95% SLE patients positive)
- non-specific (1/5 general people positive)
If ANA negative, they don’t have SLE. If its positive, doesn’t mean they definitely have SLE.
Anti-dsDNA
- moderate specificity (60% SLE patents positive)
- high specificity
If anti-dsDNA positive, they definitely have SLE. If its negative doesn’t mean they definitely don’t have SLE
What drug are most patients with systemic lupus erythematosis (SLE) on?
Hydroxychloroquine
What is used in the treatment of mild, moderate and severe systemic lupus erythematosis (SLE)?
Mild
- hydroxochloroquine
- topical steroids (low dose <15mg/day)
Moderate
- DMARDs (methotrexate, azathioprine)
- oral steroids (moderate dose 0.5mg/day)
Severe
- cyclophosphamide
- IV steroids
- biologics if resistance (ritixumab)
What is the most important investigation to do if systemic lupus erythematosis (SLE) is suspected/confirmed and what are you looking for?
Urinalysis to see if renal involvement
Proteinuria/heamaturia would suggest lupus nephritis
What tests are used to monitor systemic lupus erythematosis (SLE)?
Measuring complement and anti-dsDNA (assesses disease activity)
Urinalysis (screen for lupus nephritis)
Blood pressure and cholesterol (assess cardiovascular risk factors, increased risk of CVD)
What is Sjogren’s syndrome?
Autoimmune condition causing disruption of lacrimal and salivary glands due to lymphocytic infiltration
How does Sjogren’s syndrome present?
Fatigue
Dry eyes, mouth, vagina
Parotid swelling
What clinical test can be useful in diagnosing Sjogren’s syndrome? What does it show?
Schirmer’s test
Assesses ocular dryness
Place filter paper in eyes and see how much water drains into paper (>5mm in 5 mins is positive)
What auto-antibodies are associated with Sjogren’s syndrome?
Anti-Ro
Anti-La
What is the general treatment of Sjogren’s syndrome?
Symptomatic eye drops and salivary replacement drops
Hydroxychloroquine for fatigue/joint pain
In what circumstances would methotrexate be indicated in the treatment of Sjogren’s syndrome?
Organ involvement (e.g. interstitial lung disease)
What can Sjogren’s syndrome occur secondary to?
Rheumatoid arthritis (RA) Systemic lupus erythematosis (SLE)
What is systemic sclerosis?
Autoimmune disorder characterised by increased collagen production causing skin tightening, Raynaud’s phenomenon and some organ dysfunction
What skin changes can be seen in systemic sclerosis?
Nose beaking
Tight skin around mouth
Sclerodactyly
What is the progression of skin damage in systemic sclerosis?
- Oedematous
- Indurative (hardening)
- Atrophic
What are the major and minor features of systemic sclerosis?
How does this help diagnosis?
Major - sclerosis of the skin of face, neck and arms
Minor - sclerodactyly, fingertip atrophy, bilateral lung fibrosis
Systemic sclerosis diagnosis confirmed with 1 major cutaneous feature and 2 minor cutaneous features
What organs can be affected by systemic sclerosis?
Lungs (bilateral lung fibrosis)
Oesophagus (osophageal dysmotility causing acid reflux)
What is the difference between limited and diffuse systemic sclerosis?
Limited systemic sclerosis
- skin of face, arms and hands/feet involved
- organ involvement occurs late
Diffuse systemic sclerosis
- skin of trunk involved (rapid development)
- organ involvement occurs early
What autoantibodies are associated with systemic sclerosis?
Which is/are more common in limited and diffuse systemic sclerosis?
Anti-centromere (associated with limited)
Anti-Scl-70 (associated with diffuse)
What is the treatment of systemic sclerosis?
No specific management
Management tailored towards specific issues
