Systemic Lupus Erythematosus Flashcards
chronic inflammatory autoimmune disease that can affect any organ but most commonly
- skin, joints, kidneys, lungs, nervous system, serous membranes
Multiple autoantibodies (against normal self)
- antinuclear antibodies
- dsDNA antibodies
Periods of relapse and remission
Systemic Lupus Erythematosus
etiology and pathogenesis of systemic erythematous lupus?
UV light
- 70% of of patients with SLE are photosensitive
- UV light damages skin cells and their DNA
Viruses
- viral infections often trigger flares
Can be hormonal
Drug induced lupus
- hydralazine
- procainamide
- minocycline
- TNF inhibitors
Main clinical features of SLE?
- non-scarring alopecia
- acute and chronic cutaneous lupus
- malar rash
- oral ulcers
- raynauds
- arthritis
- childhood SLE: fever, neurological disease, renal disease
what test should be done for suspected SLE?
- CBC with differential white cell count
- Inflammatory markers: ESR, CRUP
- creatinine
- urinalysis
- ANA: negative ANA essentially rules out SLE, if done with immunofluorescence on cells, ELISA not as sensitive
If you get a positive ANA- what is the next step?
Look at the titer
- > 1:160 may be significant
- 1/80 not significant unless very suggestive symptoms or physical findings
- < 1/80 not significant
Why was it ordered?
- symptoms
- physical findings
Are there other explanations?
- thyroid diseases- hypothyroidism
- infections: parvovirus B19, lyme disease, etc.
- family history
- other autoimmune diseases
what further testing can be done with after a positve ANA?
ENA panale: many different disease associations
dsDNA- associated specifically with SLE
Complement c3, c4- looks at disease activity
Treament of SLE?
Education
- about lupus/support groups
- smoking cessation
- sun protection
- pregnancy planning
Hydroxychlorquine
- TLR 7 & 9 block
- reduces autoimmunity (interferon-alpha, immune complexes)
Corticosteroids
- disease flares
- severe manifestations (Renal, CNS)
Immunosuppressive and immunomodulationg medications
- azathioprine
- cyclophospamide
- methotrexate
- mycophenolate
Belimumab: blocks b-cell activation
anirfolumab: blocks type 1 interferon receptor
voclosporin: calineurin inhibitor, inhibits T-cells
Rituximab
other calcineurin inhibitors- cyclosporin, tacrolimus
How to monitor patients with SLE
- Follow patients 2-3 times per years (more ofthen the disease is active)
Laboratory parameters
- CBC: look for neutorpenia, lymphopenia and high/low platelet count
- renal funtion: BUN/creatinine, urinalysis and urine protein/creatinine ratio
- tests of inflammation: ESR, C-reactive protein
- specific tests for SLE activity: dsDNA antibodies (low is good), serum complement levels(low is bad) \
- don’t recheck ANA or other diagnostic antibodies
challenges in the treatment of patients with SLE
- accelerated atherosclerosis
- antiphospholipid syndrome
- nephritis
- contraception and estrogen use
- pregnancy
Autoantibodies
- cardiolipin
- beta 2 glycoprotein 1
clotting assay
- lupus anticoagulant
recurrent thrombosis
- arterial, venous
History of recurrent fetal loss
antiphospholipid syndrome
- usually requires kidney biopsy for diagnosis and treatment selection
- induction includes: high dose steroids and immunosuppressive medications- cyclophosphamide, mychophenolate, voclosporin, belimumab
- maintenance includes: azathioprine, mycophenolate
Lupus nephritis
what contraceptives are safe in lupus?
- barrier methods or IUD are safe and recommended
- oral contraceptives: Unclear if OCT contribute to increased disease activity
- increased thrombosis risk from estrogen containing OCT (antiphospholipid syndrome)
SLE and pregnancy
Risk to the mother
- SLE often flares during pregnancy
- active nephritis can be fatal
- APS: increased risk of thrombosis
- pre-eclampsia
Risk to fetus
- miscarriage- APS
- impaired growth
- prematurity (< 37 weeks- 40.5)
- neonatal lupus syndrome
- complete heart block
- SSA
Best time to conceive when the disease is not active
Most pregnancies are successful if things are done right
Management of SLE flares during pregnancy
Steroids
- prednisone- doses less than 20mg do not reach fetus
- IV methlyprednisone or dexmethasone for serious problems
NSAIDs
- may interfere initially, not during third trimester
Hydroxychloroquine
- better outcome for mother and baby
Azathioprine
Heparin for antiphospholipid syndrome
