Systemic Lupus Erythematosus Flashcards
Male to female ratio of SLE.
1:10
Three groups of predisposing factors for SLE.
- genetic factors
- hormonal factors
- environmental factors
Which two antigen serotypes are commonly seen in individuals with SLE?
- HLA-DR2
2. HLA-DR3
Which pathway of complement is often affected in individuals with SLE?
classical pathway (C1q, C2 and C4)
What hormone is associated with SLE?
estrogen -> hyperestrogenic states -> increassed risk of SLE
What drug category can cause a hyperestrogenic state?
oral contraceptives
Name two drugs that can cause DILE.
- procainamide
2. hydralazine
What environmental factors increase the risk of developing SLE?
- cigarettes
- silica
- UV rays
- EBV infection
Describe the autoantibody development theory in SLE.
deficiency of classical complement proteins -> failure of macrophages to phagocytose immune complexes and apoptotic cell material -> dysregulated, intolerant lymphocytes targeting normally hidden intracellular antigens -> autoantibody production
Describe the autoimmune reaction theory in SLE.
- type III hypersensitivity -> AB-AG complex formation in microvasculature -> complement activation and inflammation -> damage to the skin, kidneys, joints, small vessels
- type II hypersensitivity -> IgG and IgM against AGs on cells e.g., RBCs -> cytopaenia
Three common constitutional clinical features in SLE.
- fatigue
- fever
- weight loss
Three common joint clinical features in SLE.
- arthritis
- arthralgia
- distal symmetrical polyarthritis
Seven common skin clinical features in SLE.
- butterfly rash
- Raynaud phenomenon
- photosensitivity -> maculopapular rash
- discoid rash
- oral ulcers
- nonscarring alopecia
- periungual telangiectasia
What’s the difference between rheumatoid arthritis and SLE arthritis?
both affect the MCP and PIP joints, but SLE does not usually lead to deformities
What cardiological condition can be caused by SLE?
SLE can cause LSE -> Libman-Sacks Endocarditis
What nephrological condition can be caused by SLE?
nephritis with proteinuria (lupus nephritis)
What pulmonary condition can be caused by SLE?
pneumonitis or interstitial lung disease
What neurological condition can be caused by SLE?
seizures or lupus cerebritis
What psychiatric condition can be caused by SLE?
psychosis
Types of CLE.
- discoid (DLE)
- subacute cutaneous (SCLE)
- acute cutaneous (ACLE)
The appearance of DLE lesions.
erythematous, inflammatory scaly plaques that are painful to remove
Distribution of DLE lesions.
- face
- head
- neck
What is a lupus band test?
a direct immunofluorescence technique that can be used to identify a continuous band of immunoreactants (e.g., IgG and complement) along the dermal-epidermal junction
Lupus band test in DLE and SLE.
- DLE -> immune complexes are only present in macroscopically visible lesions
- SLE -> immune complexes can also be present in the skin that appears normal
