SLE Flashcards
Abnormal immune responses in SLE include: (4)
- Activation of innate immunity
- Lowered activation thresholds and abnormal activation pathways
- Ineffective regulatory CD4, CD8, T cells
- Reduced clearance if immune complexes and of apoptotic cells
Genetic signature in peripheral blood cells of 50-80% of SLE patients
Upregulation of genes induced by Interferons
DRVVT stands for
Dilute Russell viper venom time
Best screening test I
ANA (Antinuclear antibody)
SLE specific
May correlate with SLE activity (nephritis, vasculitis)
Anti-dsDNA
Specific for SLE
No correlation to activity
More common in blacks and asians more than whites
Most patients also have anti-RNP
Anti-Sm
NOT specific for SLE
high titers associated with syndromes that have overlap features of several rheumatic syndromes
Anti-RNP
Not specific for SLE
Sicca syndrome
Predisposes to subacute cutaneous lupus and to neonatal lupus with congenital heart block
Decreased risk for nephritis
Anti SS-A
Anti-Ro
Associated with dec risk of nephritis
Anti-Ro(SS-A)
Anti-La (SS-B)
Drug induced lupus marker
Antihistone
Marker predisposes to thrombpcytopenia, fetal loss, clotting
Antiphospholipid (cardiolipin, beta 2 glycoprotein 1, lupus anticoagulant)
Measured as direct Coombs test; small proportion develops overt hemolysis
Anti erythrocyte
May correlate to active CNS lupus
Antineuronal
Antiribosomal P
Most common predisposing genes known
HLA DRB1 *0301 *1501
HLA DR3
Female sex is permissive for SLE because
Higher antibody production
Exposure to estrogen pills or HRTs 1.2-2x risk
Hormones, genes on chromosome X
Environmental stimuli may influence SLE
UV light causes flare in 70% of patients
EBV
Current tobacco Smoking OR 1.5
Prolonged silica exposure
Most common blood vessel pathology
Leukocytoclastic vasculitis
Skin biopsy findings
Ig deposits at dermal epidermal junction
Injury to basal keratocytes
Inflammation dominated by T lymphocytes
Classification of Lupus Nephritis:
MESANGIAL immune deposits by immunofluorescence but normal glomeruli by light microscopy (LM)
CLASS I: Minimal Mesangial Lupus Nephritis
Classification of Lupus Nephritis:
MESANGIAL hypercellularity OR matrix expansion by LM, +mesangial immune deposits
CLASS II: Mesangial PROLIFERATIVE Lupus Nephritis
Classification of Lupus Nephritis:
Active or inactive focal, segmental, or global GN involving involving = 50% of glomeruli
WITH focal SUBENDOTHELIAL immune deposits
With or without mesangial alterations
CLASS III: FOCAL Lupus Nephritis
Classification of Lupus Nephritis:
Active or inactive focal, segmental, or global GN involving involving >/= 50% of glomeruli
WITH diffuse SUBENDOTHELIAL immune deposits
With or without mesangial alterations
CLASS IV: DIFFUSE Lupus Nephritis
Classification of Lupus Nephritis:
Global or segmental SUBEPITHELIAL immune deposits or sequelae by LM, IF or EM
With or without mesangial alterations
CLASS V: MEMBRANOUS Lupus Nephritis
May occur in combination with III or IV (still classified as V)
May show advanced sclerosis
Classification of Lupus Nephritis:
>/= 90% of glomeruli globally sclerosed
CLASS VI: Advanced SCLEROTIC Lupus Nephritis
SLICC CLINICAL
Acute or chronic cutaneous Lupus Oral or nasal ulcers Non scarring alopecia Arthritis Serositis Neurologic seizures psychosis, mononeuritis Hemolytic anemia Leukopenia <4000 or lymphopenia <1000 Thrombocytopenia <100,000 Renal- protein:crea ratio >/= 0.5, RBC casts, biopsy
SOAP BRAIN
SLICC IMMUNOLOGIC
ANA anti dsDNA Ant Sm Antiphospholipid Low serum complement Direct Coombs test (+)
Most common chronic dermatitis in SLE
Discoid lupus erythematosus
Only 5% have SLE
And among SLE ONLY 20% have DLE
Most serious manifestation of SLE
Nephritis
Indicators of dangerous proliferative glomerular damage
Microscopic hematuria
Protenuria >500mg/24hr
GC induced psychosis occurs during first weeks of treatment at what doses of steriods
> /= 40mg prednisone and equivalent
Most common manifestation of diffuse CNS lupus
Cognitive dysfunction (memory/reasoning)
Most frequent hema manifestation
Anemia of chronic disease (normo- normo-)
Diagnosis of APAS
1 or more clotting episodes and/OR repeated fetal loss
2 or more positive antiphospholipid tests at least 12 weeks apart
SLEDAI score of active disease
Greater than 3
Antimalarial that reduces flares and accrual of tissue damage over time
Hydroxychloroquine
Side effect is retinal toxicity
Amenorrhea, leukopenia and nausea as side effect:
MMF or cyclophosphamide?
Cyclophosphamide: an alkylating agent
Diarrhea as side effect:
MMF or cyclophosphamide?
Mycophenolate mofetil: lymphocyte-specific inhibitor of IMP
Pregnant with active SLE tx
Hydroxychloroquine [category D]
Prednisone/ prednisolone at lowest dose possible (deactivated by placental enzyme)
Azathoprine may be added [category D]
*MTX [category X]
If to start azathioprine, screen for this enzyme deficiency or else: higher risk for bone marrow suppression
Thiopurine S-methyltransferase (TPMT): required to metabole 6-mercaptopurine product of azathioprine
SLE patient taking NSAID are more prone to this CNS complication
Aseptic Meningitis
Quinacrine side effect
Diffuse yellow skin
May have a role in dermatitis, arthritis but probably not in
MTX: a folinic acid antagonist
Has adverse effects of: hemorrhagic cystitis (less with IV), carcinoma of the bladder, VZV infection
CYCLOPHOSPHAMIDE
Lupus nephritis tx mainstay
SYSTEMIC GC:
Methylprednisolone Na succinate 0.5-1 mg/kg/day OR 500-1000 mg IV x 3 days followed by
Prednisone 0.5-1 mg/kg/day PO x 4-6 weeks then tapered
Rash
Congenital heart block
Cardiomyopathy
Neonatal lupus
Target INR in lupus and APS
A. 1 episode of venous clotting
B. With RECURRENT clots
A. 2 to 2.5
B. 3 to 3.5
Lupus dermatitis SPF
30
Lupus dermatitis tx
Topical sunscreen/ GC/ tacrolimus; and antimalarials
Retinoic if not improved
Systemic GC for extensive dermatitides-> overlap with a secon medication while tapering
Criteria likely to respond to BELIMUMAB (considered after other approaches fail or are not tolerated
SLEDAI at least 10
(+) anti-dsDNA
low serum complement
-> robust clinical activity
True or False:
All drug-induced lupus are ANA positive.
True
SLICC 93% specific, 92% sensitive
> /= 4 criteria satisified,
atleast 1 clinical, 1 immunologic
Topical sunscreens SPF
30