31: Multi-system Autoimmune Conditions Flashcards
list examples of connective tissue diseases
- SLE
- systemic sclerosis
- Sjogren’s syndrome
- Auto-immune myositis
- mixed connective tissue disease
list examples of systemic vasculitidies
- giant cell arteritis
- granulomatosis with polyangiitis (Wegeners)
- miscroscopic polyangiitis
- eosinophilic granulomatosis with polyangiitis (Churg-strauss syndrome)
who is usually affected by SLE? (epidemiology)
- 9x more common in women
- most common in afro-caribbean and Asian origin
- disease onset most commonly occurs in 20s-30s
SLE pathogenesis
- immune response against endogenous nuclear antigens
- immune complex formation
- complement activation
- tissue injury
SLE aetiology
genetic
hormonal
environmental: UV light, drugs, infections
SLE presentation
SLE is a heterogeneous disease and some symptoms can be nonspecific, leading to a delay in diagnosis.
The classical presentation of SLE usually has some combination of:
- Systemic upset (fever, myalgia, fatigue and weight loss)
- Joint and/or skin involvement
what antibodies are associated with SLE?
- Usually positive for ANA, not specific for SLE
- Anti-ds DNA, seen in 60% of patients, highly specific
- Anti-Sm (10-30%), highly specific
- Anti-Ro
- antiphospholipid antibodies
when should a diagnosis of SLE be considered?
- usually seen in women of childbearing age
- constitutional symptoms of fever, weight loss, malaise and severe fatigue
- skin rash and/or stomatitis
- arthritis
- pleuritic chest pain
- renal disease
- cytopenia
systemic slerosis aetiology
- environmental: silica, solvents, viral infections
- genetic predisposition
systemic sclerosis pathogenesis
- vascular damage (microcirculation)
- immune system activation/inflammation
- fibrosis
what antibodies are implicated in Limited cutaneous systemic sclerosis (CREST)
anti-centromere antibodies
which antibodies are indicated in Diffuse cutaneous systemic sclerosis?
anti Scl70 antibodies
what is Sjogren syndrome?
an inflammatory autoimmune disorder characterised by decreased lacrimal and salivary gland secretion, leading to manifestations of dry eyes and mouth.
which antibodies are implicated in Sjogren’s syndrome?
- anti Ro (SSA)
- anti La (SSB) antibodies
sjogren’s syndrome presentation
- dry eyes
- dry mouth
- parotid gland enlargement
- 1/3 have systemic upset e.g. fatigue, fever, myalgia, arthralgia, dry skin
Sjorgen’s syndrome complications
- lymphoma
- neuropathy
- cutaneous vasculitis
- interstitial lung disease
- renal tubular necrosis
describe polymyositis and dermatomyositis
Polymyositis and dermatomyositis are inflammatory muscle diseases characterized by bilateral, proximal muscle weakness, and in the case of dermatomyositis, skin rashes.
what antibodies are indicated in myositis?
anti Jo1 antibodies
giant cell arteritis classification criteria
3 of the following:
- age at onset > than 50 years
- new headache
- temporal artery tenderness/reduced pulsation
- ESR > 50
- abnormal temporal biopsy
list some investigations for giant cell arteritis
- temporal artery biopsy
- US doppler
- CT angiogram, MR angiogram
- FDG PET
GCA complications
- irreversible visual loss
- aortic aneurysms
- arterial stenosis and limb ischaemia
- stroke
GCA treatment
- urgent initiation of high dose prednisolone
- PPI
- bone protection
- steroid sparing medication
which antibodies are implicated in Granulomatosis with Polyangiitis (Wegener’s) (GPA)?
cANCA
anti PR3 antibodies
Granulomatosis with Polyangiitis (Wegener’s) (GPA) pathogenesis
Necrotising granulomatous inflammation
Usually involving the upper and lower respiratory tract
Hearing loss, sinusitis, hemoptysis
Necrotising glomerulonephritis is common
Microscopic polyangiitis (MPA) pathogenesis
- Necrotising vasculitis, with few or no immune deposits, predominantly affecting small vessels
- Granulomatous inflammation is absent
- Renal and pulmonary involvement common
which antibodies are implicated in microscopic polyangitis?
pANCA
anti MPO antibodies
Eosinophilic Granulomatosis with Polyangiitis (Churg Strauss) (EGPA) pathogenesis
- 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 implicated in Eosinophilic Granulomatosis with Polyangiitis (Churg Strauss) (EGPA)?
40-60% anti MPO antibodies positive
what is the likely diagnosis?
SLE
