Systemic lupus erythematosus Flashcards
What is SLE?
Autoimmune connective tissue disease
Complex multi-system disease with various presentations
Characterised by remission and flares
Who is it common in?
Females 9x more likely
Age >30 yrs
What puts you at high risk of SLE
Can be familial
Oestrogens- thought to be permissive of autoimmunity
Which ethnicity have more severe disease and prognosis
People of colour
Asians, Hispanic, Afro-Caribbeans
Caucasians suffer from more ….
more skin and joint involvement
COCP could cause …. in SLE
flare-ups in pt with lupus
What is the pathophysiology?
- inadequate T cell suppressor activity with increased B cell activity
- most patients have antibodies to certain cell
nucleus components
Extra:
Altered clearance of apoptotic bodies/ increase apoptosis in SLE → if not removed, apoptotic bodies degrade → release of potential auto-antigens → immune complexes formed → immune complexes can stimulate cells to produce IFN which cause inflammation
patients often have low C1, C2, C3, C4 counts - these help clear apoptotic proteins
What are the main symptoms and signs of SLE : mneumonic
SOAP BRAIN- mneumonic
Fever to fight all inflammation below
S- serositis- plerisy, pericarditis- chest pain, trouble breathing, meningitis
O- oral ulcers- usually painless, palate most specific
A- arthritis- small joints nonerosive
P-photosensitivity - malar or discoid rash (naso-labial sparing)
B- Blood disorders - Low WCC, Lymphopenia, thrombocytopenia, haemolytic anaemia
R- renal involvement- glomerulonephritis
A- autoantibodies- ANA positive >90%
I- immunological tests - low complements
N- neurological disorder- seizures or psychosis
What are the visible symptoms ?
Alopecia- Inflammation on scalp- Hairloss
Malar rash/discoid rash with naso-labial sparing
Mouth ulcers
Joint inflammation- synovitis
Raynauds phenomenon
Nail fold vasculopathy
What would you ask the patient when questioning flare-up ?
- Increased fatigue
- Fever
- Arthralgia
- weight changes
What investigations show high disease activity?
Anti-dsDNA titre rises with disease activity
Complement proteins (C3/C4)- fall with increased disease activity
What investigations to do for SLE?
- Autoantibodies
- Full blood count (normocytic anaemia of chronic disease)
- C3 and C4 levels (decreased in active disease)
- CRP - normal
- ESR and plasma viscosity- elevated due to increased Ig
- Immunoglobulins (raised due to activation of B cells with inflammation)- Coombs- detect autoantibodies
- U&Es, LFTs
Urinalysis and urine protein:creatinine ratio for proteinuria in lupus nephritis
Skin or renal biopsy can be diagnostic (renal can help prognosticate)
What will the FBC show in SLE?
eukopenia→ lymphopenia
thrombocytopenia
anaemia- low Hb (of chronic disease- normocytic normochromic)
What do you want to rule out in SLE symptoms?
Infection
What autoantibodies do we test for? Which is most common?
anti-nuclear antibodies- ANA +ve (95% of cases)
Anti-Ro
Anti-La
Anti-dsDNA
Anti- Sm
Antiphospholipid antibodies
Which ANA antibodies are clinically relevant in SLE?
IgG
Which antibodies are specific to SLE? What are they useful for?
Anti-dsDNA and Anti-Smith
Anti- ds DNA- Useful in monitoring disease activity and response to treatment.
What criteria do we use for diagnosis of SLE?
SLICC criteria
At least 4 criteria, with at least one clinical criterion AND one immunologic criterion
OR
Lupus nephritis as the sole clinical criterion in the presence of ANA or anti-dsDNA antibodies.
What conservative management would you advise?
Sun protection (UV light triggers SLE as alters the structure of DNA makes it more immunogenic)
Healthy lifestyle advice due to CVD risk
- Smoking cessation
What drugs trigger SLE - like symptoms
Isoniazid
Minocycline
TNF inhibitors
Treatment of SLE: First line?
Hydroxychloroquine (HCQ) - improves rash and arthralgia
Corticosteroids- short course prednisolone for flare-ups
NSAIDs - pain management
What other drugs are used other than first line ?
DMARDS - mycophenolate mofetil, methotrexate , azathioprine (preg safe)
Biologics- rituximab and Belimumab
Low dose ramipril (ACEi) - good for proteinuria, managing BP
What other drugs are used other than first line ?
DMARDS - mycophenolate mofetil, methotrexate , azathioprine (preg safe)
Biologics- rituximab and Belimumab
Low dose ramipril (ACEi) - good for proteinuria, managing BP
How does Rituximab work?
monoclonal antibody that targets the CD20 protein on the surface of B cell
Some complications ?
Recurrent miscarriage is common in systemic lupus erythematosus
High CVD Risk- Coronary artery disease and HTN
Interstitial lung disease
Lupus nephritis →end-stage renal failure
Neuropsychiatric SLE
