Mini Symposium: Multisystem Autoimmune Disease Flashcards
Name some connective tissue diseases?
- Systemic Lupus Erythematosus
- Systemic sclerosis
- Sjogren’s syndrome
- Auto-immune myositis
- Mixed connective tissue disease
Name some systemic vasculitides?
- Giant cell arteritis
- Granulomatosis with polyangiitis (Wegeners)
- Microscopic polyangiitis
- Eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome)
What is the approach to diagnosing a patient with multisystem inflammatory disease?
•Cardinal clinical features: history & examination •Bedside investigations •Immunology •Imaging •Tissue diagnosis Exclusion of differential diagnoses
What are some mimics of multi system inflammatory disease?
- Malignancy - lymphoma
- Infections - endocarditis, hepatitis B and C, TB, HIV
- Drugs - cocaine, Minocyline, Propylthiouracil
Rarer:
•Cardiac myxoma
•Cholesterol emboli
•Scurvey
Who gets SLE?
- Female:Male 9:1
- Onset - 15-50 years
- Afro-Caribbean>Asian>Caucasian
What are the genetic factors that cause SLE?
- High concordance in monozygotic twins
- Sibling risk for developing SLE is 30-fold higher than in the general population
- Polygenic mode of inheritance
What are the environmental factors that cause SLE?
- UV light
- Drugs
- Infections
What other factors may cause SLE?
Hormonal
Describe the pathogenesis if SLE
- Immune response against endogenous nuclear antigens (break in immunological tolerance)
- Immune complex formation
- Complement activation
- Tissue injury
What is the classification criteria for lupus?
4 of the following:
1) Malar rash (butterfly rash)
2) Discoid rash (raised, scarring, permanent marks, alopecia)
3) Photosensitivity
4) Oral ulcers
5) Arthritis (2 joints at least)
6) Serositis (pleurisy or pericarditis)
7) Renal (significant proteinuria or cellular casts in urine)
8) Neurological (unexplained seizures or psychosis)
9) Haematological (low WCC, platelets, lymphocytes, haemolytic anaemia)
10) Immunological (anti ds-DNA, Sm, cardiolipin, lupus anticoagulant, low complement)
11) ANA (anti-nuclear antibody)
How is kidney involvement classed in SLE?
•Lupus nephritis important cause of morbidity and mortality •Renal involvement can be single organ involvement I - minimal mesanginal II - mesanginal proliferative III - focal IV - diffuse V - membranous VI - advanced sclerosing
When to consider a diagnosis of SLE?
- Usually seen in women of childbearing age with
- Constitutional symptoms of fever, weight loss, malaise, and severe fatigue
- Skin rash and/or stomatitis (mouth and lips)
- Arthritis
- Pleuritic chest pain
- Renal disease
- Cytopenia
What are the autoantibodies seen in SLE?
- ANA
- Anti-ds DNA
- Anti-Sm (Smith)
- Anti-Ro
- Antiphospholipid antibodies
What percentage of SLE cases have a positive ANA?
95%
What makes ANA testing less useful in diagnosing SLE?
- Not specific for SLE
- Seen in many inflammatory, infectious, and neoplastic diseases
- Seen in 5% to 15% of healthy population
What percentage of SLE cases are positive for anti-ds (double-stranded) DNA?
- 60%
* Highly specific for SLE
What is anti-ds DNA closely associated with?
Nephritis
What percentage of SLE cases are positive for anti-sm (Smith)?
- 10-30%
* Highly specific for SLE
What is the clinical significance of being positive for anti-Ro autoantibody?
- Risk of foetal congenital heart block
- Neonatal lupus
- Foetal cardiac monitoring from 16weeks onwards
What is the clinical significance of being positive for antiphospholipid antibodies?
- Arterial/venous thrombosis
* Miscarriages
What types of antiphospholipid antibodies are relevant to SLE?
- Anti-cardiolipin
* Lupus anticoagulant
What is systemic sclerosis also known as?
Scleroderma (fibrosis of skin and internal organs)
How can scleroderma be classified?
•Localised scleroderma
•Systemic sclerosis (SSc):
-Limited cutaneous systemic sclerosis (CREST)
-Diffuse cutaneous systemic sclerosis
What is localised scleroderma limited to?
Fibrotic involvement of the skin and subcutaneous tissue - should be reassured no risk of systemic involvement
How are limited cutaneous systemic sclerosis (CREST)
and diffuse cutaneous systemic sclerosis defined?
- Limited - skin involvement distal to knees and elbows (slow progression)
- Diffuse - skin thickening proximal to knees and elbows and trunkal involvement (fast progression with organ involvement - usually lungs)
Who gets scleroderma?
- UK Prevalence: 24/100,000
- UK Incidence: 10/1,000,000
- Onset: 30-50 years
- Female : Male 3:1
What is the aetiology of scleroderma?
•Unknown •Possible environmental factors: -Silica -Solvents -Viral infections •Genetic predisposition
What is the pathogenesis of scleroderma?
- Vascular damage (microcirculation)
- Immune system activation/Inflammation
- Fibrosis
What are the antibodies associated with limited cutaneous systemic scerosis?
•Anti centromere antibodies
What are the antibodies associated with diffuse cutaneous systemic scerosis?
•Anti Scl70 antibodies
What are the systemic involvements associated with limited cutaneous systemic scerosis?
- Pulmonary hypertension
* Gastrointestinal
What are the systemic involvements associated with diffuse cutaneous systemic scerosis?
- Pulmonary fibrosis - leading cause for mortality and morbidity
- Renal crisis
- Small bowel bacterial overgrowth
How should scleroderma not be treated?
•Not high doses of steroids (max 20mg prednisolone/day) due to potential renal crisis
Who gets Sjorgen’s syndrome?
- Prevalence: 1 in 100
- Incidence: 4 in 100,000
- Onset: 40-50yrs
- Female : Male 9:1
What are the symptoms of Sjorgen’s?
- Dry eyes and mouth
- Systemic autoimmune disease characterised my lymphocytic infitrate or salivary and tear glands
- Can be primary or secondary to other autoimmune disease
What are the investigations used to diagnose Sjorgen’s? (what antibodies are tested for?)
•Antibody testing:
-Anti Ro (SSA)
-Anti La (SSB) antibodies
Salivary gland biopsy (taken from lower lip) - should show inflammation
What else can cause dry eyes and mouth?
- Menopause
- Radiotherapy
- Infections
- Contact lenses
How long do dry eyes need to be present for to diagnose with Sjorgen’s?
3 months
What are the clinical signs of Sjogren’s?
•Parotid gland enlargement •1/3 have systemic upset: -fatigue -fever -myalgia -arthralgia -dry skin
What are the complications of Sjorgen’s (5)?
- Lymphoma
- Neuropathy
- Cutaneous vasculitis
- Interstitial lung disease
- Renal tubular acidosis
What are the complications of Sjorgen’s (5)?
- Lymphoma
- Neuropathy
- Cutaneous vasculitis
- Interstitial lung disease
- Renal tubular acidosis
How common are autoimmune myopathies?
Rare
What is the epidemiology of polymyositis and dermatomyositis?
- Rare: 6/million incidence
- More common in females (ratio 3:1)
- Peak incidence is in 50– 60 year olds
- Increased risk of malignancy
What are the signs and symptoms of myositis?
•Muscle weakness - proximal and symmetrical (predominant symptom)
•Cutatneous involvement:
-Gottron’s papules (80%)
-Heliotrope rash (30-60%)
What investigations are used to diagnose myositis?
- CK test - should be raised
- EMG (electromyogram)
- MRI
- Muscle biopsy - gold standard
What will increase risk of interstitial lung disease in myositis?
•Anti Jo1 antibodies
What is mixed connective tissue disease?
A chronic disorder that has overlapping features of two or more systemic rheumatic disorders
How may mixed connective tissue disease present?
- Raynaud’s
- Soft tissue swelling/sclerodactyly
- Myositis
- Arthralgia
How are vasculitides classified?
Large, medium and small
What are the types of large vessel vasculitis (2)?
- Takayasu arteritis - Far East, young women <50
* Giant arteritis - 50+
What are the types of medium vessel vasculitis (2)?
- Polyarteritis nodosa - associated with hep B
* Kawasaki disease - children
What are the types of small vessel vasculitis (2)?
•ANCA-associated vasculitis (without immune complex deposition)
•Immune complex SVV
THE VACULITIDES
What is the GCA classification criteria?
- 3 of the following (classic temporal arteritis):
- Age at onset ≥50 years
- New headache
- Temporal artery tenderness/reduced pulsation
- Jaw claudication - pain on chewing
- ESR≥50
- Abnormal temporal biopsy
What are the investigations used to diagnose GCA?
- Temporal artery biopsy
- Ultrasound doppler - halo sign
- CT and MR angiograms (for large vessel involvement)
- FDG PET - aortic inflammation
What are the complications of GCA?
- Irreversible visual loss
- Aortic aneurysms
- Arterial stenosis and limb ischaemia
- Stroke
How is GCA treated?
- Urgent initiation of high dose Prednisolone
- 40-60mg per day, gradually tapered
- PPI - proton pump inhibitors
- Bone protection
- Steroid sparing medication
What are the subtypes of ANCA-associated vasculitis?
- Granulomatosis with polyangiitis (Wegener’s) (62.5%)
- Microscopic polyangiitis (16.7%)
- Eosiniphilic granulomatosis with polyangiitis (20.8%)
What is the epidemiology of ANCA-associated vasculitis?
- Overall incidence 15/million
* Overall prevalence 150/million
How is Granulomatosis with polyangiitis (Wegener’s) characterised?
- Necrotising granulomatous inflammation
- Usually involving the upper and lower respiratory tract
- Hearing loss, sinusitis, hemoptysis
- Necrotising glomerulonephritis is common
- Subglottic stenosis - silent or strider and voice hoarseness
What antibodies are associated with Granulomatosis with polyangiitis (Wegener’s)?
- cANCA
* Anti PR3 antibodies
How is Microscopic polyangiitis (MPA) characterised?
- Necrotising vasculitis, with few or no immune deposits, predominantly affecting small vessels
- Granulomatous inflammation is absent
- Renal and pulmonary involvement common
- Seronegative inflammatory arthritis for years before renal involvement
What antibodies are associated with Microscopic polyangiitis (MPA)?
- pANCA
* Anti MPO antibodies
How is Eosiniphilic granulomatosis with polyangiitis characterised?
- Eosinophil rich and necrotising granulomatous inflammation often involving the respiratory tract
- Late onset asthma, nasal polyps and eosinophilia
- Necrotising vasculitis predominantly affecting small to medium vessels
- Neurological involvement
- Cardiac, gastrointestinal – poor prognosis
What antibodies are associated with Eosiniphilic granulomatosis with polyangiitis?
•Anti MPO antibodies positive - 40-60% positive