Autoimmune connective tissue disease Flashcards
What antibodies are associated with polymyositis and dermatomyositis?
- Anti Jo-1
- Anti Mi-2
What antibody is associated with systemic sclerosis?
Anti-Scl70
Describe Polymyositis and dermatomyositis?
- Proximal skeletal and smooth muscle inflammation
- Autoimmune-mediated
- Myalgia -> dysphagia, dysphonia, respiratory weakness
- Skin involvement in dermatomyositis
Clinical features of PM and DM?
- Symmetrical proximal muscle weakness / pain
- Affect LLs more than ULs
- Difficulty rising from chair, climbing stairs and lifting
- Fever, weight loss, fatigue
What should always be done in polymyositis and dermatomyositis?
Screen for cancer
Describe Dermatomyositis?
- Myositis plus skin signs:
- Rash over back and shoulders
- Discolouration of the eyelid +/- periorbital oedema
- Nail-fold capillary dilation
- Gottron’s papules (rough red papules over knuckles)
- Raynauds
- Rash over back and shoulders
What are the extra-muscular signs in both polymyositis and dermatomyositis?
- Fever
- Arthralgia
- Raynaud’s
- Interstitial lung fibrosis
- Myocardial involvement
Describe the tests for polymyositis and dermatomyositis?
- Creatine kinase can be raised
-
Muscle biopsy (use MRI to identify abnormal muscle for biopsy)
- Confirms diagnosis: Fibre necrosis and inflammatory infiltrate
- Autoantibody associations
- Anti-Mi2, Anti-Jo1
- Electromyography (EMG)
- Can identify non-AI/inflammatory myopathies
- Screen for malignancy
Namr some differentials for polymyositis and dermatomyositis?
- Drugs
- Infection (HIV)
- Rhabdomyolysis
- Muscular dystrophy
- Inclusion-body myositis
- Carcinomatous myopathy
- Endocrine/metabolic myopathy
What drugs can cause polymyositis and dermatomyositis?
- Statins
- Colchicine
- Chloroquine
- Penicillamine
Describe the mangagement of polymyositis and dermatomyositis?
- Prednisolone PO
- Methylprednisolone IV
- If respirsatory/pharyngeal weakness
- Resistant cases:
- Methotrexate + mycophenolate
- Skin predominant disease
- Hydroxychloroquine
Describe systemic sclerosis?
- AI disorder of connective tissue causing:
- Fibrosis of skin, organs and vasculature
- Autoantibodies:
- ANA, anti-centromere
Clinical features of Systemic sclerosis?
- Skin
- Non-pitting oedema of fingers, shiny, taut skin
- Raynaud’s phenomenon
- Arthralgia, tenosynovitis, muscle weakness
- Dysphagia, odynophagia
- Pulmonary hypertension
What is scleroderma?
- Systemic sclerosis without internal organ invovlement
- Tightening and fibrosis of skin
Describe Limited cutaneous systemic sclerosis?
- Raynauds
- Scleroderma of face and distal limbs
- Anti-centromere antibodies
- A subtype of limited systemic sclerosis is CREST syndrome
Treatment for limited systemic sclerosis?
- Sildenafil
- Bosentan
Describe diffuse skin involvement of systemic sclerosis?
- Can involve the whole body
- Anti-Scl70 anitbodies in 70%
- Anti-RNA polymerase in 20%
- Monitor BP and perform regular echos and spirometry
What are the indicators of a poor prognosis in systemic sclerosis?
- Older age
- High ESR
- Proteinuria
- Pumonary HTN
- Diffuse disease
Describe the management of systemic sclerosis?
- No cure
- Raynaud’s
- Avoid cold, thick socks/gloves, sildenafil
- Interstitial lung disease
- Glucocorticoids + cyclophosphamide
- Hypertension
- Regular ACE-i/ARBs
- Pulmonary HTN
- Bosentan, heart-lung transplant
Describe Primary Sjogren’s syndrome?
- Lymphocytic infiltration of salivary and lacrimal glands
- => Glandular fibrosis and exocrine failure
Risk factors for Primary Sjogren’s syndrome?
- 40-60 years
- Female
- HLA-B8/ HLA-DR3
Clinical features of Primary Sjogren’s syndrome?
- Keratoconjunctivitis
- Non-erosive arthralgia
- Enlarged salivary glands
- Raynaud’s phenomenon
Autoantibodies detected in Primary Sjogren’s syndrome?
- Rheumatoid factor
- Antinuclear antibody (ANA)
- Anti-Ro, Anti-La
- Thyroid autoantibody
Describe the diagnosis of Primary sjogren’s syndrome?
- Schirmer tear test
- Normal is >6mm of wetting
- Elevated ESR and hypogammaglobulinaemia
- Positive autoantibody
Management of Primary sjogren’s syndrome?
- No disease modifying treatment
- Tear substitiutes
- Lubrication for vaginal dryness
- Hydroxychloroquine for skin and MSK features
Read the presentation of Sjogrens syndrome
Read the presentation of systemic sclerosis
Presentation of idiopathic inflammatory myopathies?
Polymyositis, dermatomyositis
Read the case presentation of SLE
Investigations into dermatomyositis?
- ANA positive
- Anti-Mi-2
- Anti-Jo-1
- SRP antibodies
Describe CREST syndrome?
- Subtype of limited cutaneous systemic sclerosis
- Calcinosis
- Raynauds
- oEsophageal dysmotility
- Sclerodactyly
- Telangiectasia
