11 - Muscle and Soft Tissue Rheumatology Flashcards
What are some autoimmune connective tissue disorders?
- SLE
- Systemic sclerosis
- Sjogren’s
- Polymyositis and Dermatomyositis
If someone has a multisystem disorder with raised ESR but normal CRP, what should you consider as the diagnosis?
SLE
What is the general pathophysiology of SLE?
Multisystemic autoimmune disease that relapses and remits
Autoantibodies made against autoantigens which then form immune complexes
- Inadequate clearance of immune complexes cause immune responses in tissues, leading to inflammation and tissue damage
What are some risk factors for developing SLE?
- Female
- Child-bearing age
- Afro-Caribbean or Asian
- 1st or 2nd degree relative
- UV light
- Drugs
What are some common symptoms and signs of lupus?
Remitting and relapsing disease that often has non specific features like malaise, fatigue, myalgia and fever
Other features: alopecia, weight loss, lymphadenopathy, Raynaud’s
What investigations can you do if you suspect lupus and what will they show?
- ESR/PV: raised
- CRP: normal
- FBC: anaemia and leukopenia
- Autoantibodies: ANA, anti-dsDNA, anti-Ro, anti-La, antiphospholipid antibodies
- C3/C4: decreased in active lupus
- Urinalysis: may have haematuria if renal disease
- Biopsy: skin and renal, can be diagnostic
If a patient with lupus has antiphospholipid antibodies, what can this increase the chance of?
- Pregnancy loss
- Thrombosis
HIGH CVD RISK IN SLE REGARDLESS
How is SLE diagnosed?
SLE can mimic other diseases. Take skin/renal biopsies
Need 4 or more criteria (with at least 1 clinical and 1 labatory)
OR
Biopsy proven lupus nephritis with positive ANA or anti-dsDNA
How can we monitor SLE activity to monitor for flares?
- Anti-dsDNA antibody titres
- C3/C4 levels (will be low in flares as consumption)
- ESR
- Urine for protein and erythrocyte casts
What are some drugs that cause drug-induced lupus?
- Isoniazid*
- TNF-a inhibitors*
- Chlorpromazine
- Phenytoin
- Hydralazine*
- Procainamide
- Minocycline
Stop drug for resolution
What are some drugs that can worsen idiopathic SLE?
- Oral contraceptives
- Sulfonamides
What is the management for lupus? (include general measure, maintenance and flares)
General measures: high factor sun-block, advice on healthy lifestyle due to CVD risk, topical steroids for skin flares, screen for co-morbidities and drug toxicity
Maintenance: Hydroxychloroquine for rash and arthralgia. NSAIDs if no renal disease. Mycophenolate mofetil, Azathioprine, Rituximab are used for steroid sparing
Flares: short course of low-dose steroids such as prednisolone, if organ damage use DMARDs or mycophenolate
How is lupus nephritis treated differently to lupus?
Intesive immunosuppression to induce remission using steroids and cyclophosphamide before maintenance
BP control needed.
What is antiphospholipid syndrome?
Antiphospholipid antibodies, often associated with SLE
Coagulation defect
Livedo reticularis
Obstetric (recurrent miscarriages)
Thrombocytopenia
What is Raynaud’s phenomenon?
- Peripheral digital ischaemia due to vasospasm.
- Painful and sequence of colour changes that are bilateral over few minutes
- Usually precipitated by cold and emotion
What is Raynaud’s syndrome?
When Raynaud’s phenomenon is idiopathic.
Common in young women. Tell them to keep warm and avoid smoking
What are some causes of Raynaud’s?
- SLE
- Scleroderma
- Dermatomyositis and polymyositis
- Sjogren’s
- Drug induced by beta blockers
- Heavy vibrating tools
- Cervical rib
- Sticky blood
How is Raynaud’s treated?
Conservative:
- Stop smoking
- Keep warm e.g gloves, handwarmers
Pharmacological:
- CCB’s like nifedipine 1st line.
- PDE-5 inhibitors like sildenafil and epoprostenol also good