SLE Flashcards
Best screening test for SLE
ANA - 98% prevalence
multiple nuclear
Correlates with disease activity, nephritis and vasculitis
Anti-dsDNA - 70% prevalence
double stranded
Specific for SLE
No definite clinical correlations
Anti-SM - 25% prevalence
protein complexed to 6 species of nuclear U1 RNA
Associated w/ Sicca syndrome, predisposes to subacute cutaneous lupus and neonatal lupus w/ congenital heart block
Associated w/ decreased risk for nephritis
Anti-Ro (SS-A) - 30% prevalence
protein complexed to hY RNA (60 kDA and 52kDA)
Usually associated w/ anti-Ro
Associated w/ decreased risk for nephritis
Anti-La (SS-B) -10% prevalence
47 kDA protein complexed to hY RNA
More frequent in DRUG INDUCED lupus
Antihistone - 70% prevalence
histones associated w/ DNA (in nucleosome, chromatin)
Predisposes to clotting, fetal loss, thrombocytopenia
ELISA - cardiolipin and B2G1
sensitive prothrombin time (DRVVT) - for lupus anticoagulant
Antiphospholipid - 50% prevalence
phospholipids, B2 glycoprotein cofactor, prothrombin
Measured as direct Coombs test
Antierythrocyte - 60% prevalence
erythrocyte membrane
Associated w/ THROMBOCYTOPENIA
NOT a useful clinical test
antiplatelet
Positive test in CSF correlates w/ active CNS lupus
Antineuronal - 60% prevalence
neuronal and lymphocyte surface antigens
Positive test in serum correlates w/ DEPRESSION or PSYCHOSIS d.t. CNS lupus
Antiribosomal P - 20% prevalence
22 y/o woman presents w/ fatigue, malaise and fever of 10 days duration, swelling hands and ankles
chest pain during inspiration
raised erythema on the cheeks, hand and ankle joints swelling and tenderness
systemic lupus erythematosus (SLE)
Mainstay treatment for life threatening SLE
systemic glucocorticoid
CLASS I: Minimal Mesangial LN
LM: normal glomeruli
IF: mesangial immune deposits
CLASS II: Mesangial Proliferative LN
LM: purely mesangial hypercellularity or mesangial matrix expansion
IF/EM: few isolated subepithelial/subendothelial deposits
start HIGH DOSE STEROIDS
CLASS III: Focal LN
GN involving <50% of glomeruli
start CYCLOPHOSPHAMIDE
CLASS IV: Diffuse LN
GN involving >50% of glomeruli
CLASS V: Membranous LN
global/segmental subepithelial immune deposits
CLASS VI: Advanced Sclerotic LN
> 90% of glomeruli globally sclerosed w/o residual activity
Treatment for non life threatening disease
analgesic and antimalarials
Treatment for arthritis/arthralgia
NSAIDs
Treatment for dermatitis, arthritis and fatigue
antimalarials - hydroxychloroquine, chloroquine, quinacrine
Treatment for lupus dermatitis
antimalarials, topical sunscreen, topical steroid and/or tacrolimus
Mainstay treatment for life threatening disease
systemic glucocorticoids
