Lupus Flashcards
Cutaneous lupus
immune system targets skin cells that can lead to red, thick and scaly rashes that may itch or burn
Drug-induced lupus and most common drugs
lupus-like disease caused by some drugs
most common drugs: hydralazine, procainamide, isoniazid
What are some other differentials for lupus?
Infections (EBV / HIV)
lymphoma / leukemia
other rheumatic disease (RA, mixed connective tissue disease)
What is only form of lupus that is itchy?
acute cutaneous lupus
What labs are important to check in lupus workup? (4)
CBC
CMP
ESR / CRP
ANA
(other antibodies)
CBC in lupus
shows -penias
CMP in lupus
can show kidney injury
ex: elevated creatinine
ESR
sedimentation rate
marker of inflammation (elevated)
CRP
c-reactive protein
marker of inflammation (elevated)
What is the first line treatment for SLE?
immunosuppressants: hydroxychloroquine and prednisone
Most common side effect of hydroxychloroquine
retinal toxicity / vision loss
Difference between nephritis and nephrotic syndrome
nephritis = RBCs in urine
Nephrotic = proteinuria more common
What do you see histologically in glomerulonephritis?
wire-loop lesion
What is the least toxic immunosuppressive medication?
hydroxycholoroquine
How long does hydroxychloroquine take to work?
6-8 weeks
MOA of hydroxychloroquine
weak base that accumulates in lysosomes which increases lysosomal pH
disrupts normal peptide assimilation
Other benefits of hydroxychloroquine
(1) an increase in the LDL receptor which
helps lowering lipids
(2) a decrease in degeneration of insulin helping glucose intolerance
(3)
inhibition of platelet aggregation and adhesion which prevents thrombosis
What 2 drugs are anti-metabolites?
methotrexate
leflunomide
leflunomide has longer half life
MOA of methotrexate
inhibition of dihydrofolate reductase
azathioprine MOA and side effects
AZA
MOA: inhibit purine synthesis
Side effects: pancytopenia due to bone marrow suppression
Mycophenolate Mofetil MOA and side effect
MMF
MOA: inhibit purine synthesis
Side effect: hepatotoxic and contraindicated in pregnancy
Cyclophosphamide MOA and side effect
cytotoxic agent
decrease DNA synthesis and induce apoptosis due to DNA damage
MOA: hepatotoxicity + increased risk of infection/malignancy
Anti-dsDNA
specific for SLE
shows disease activity
shows glomerulonephritis
high specificity, low sensitivity
Anti-histone
shows drug-induced lupus
and SLE
Anti-Smith
high specific low sensitivity
Which complement proteins are decreased in SLE?
C3 and C4
