General Features
Systemic lupus erythematosus (SLE)
is a chronic disease with many manifestations. SLE
is an autoimmune disease in which the body's own
immune system is directed against the body's own
tissues. The etiology of SLE is not known. It can
occur at all ages, but is more common in young
women. The production of autoantibodies leads to
immune complex formation. The immune complex
deposition in many tissues leads to the
manifestations of the disease. Immune complexes
can be deposited in glomeruli, skin, lungs,
synovium, mesothelium, and other places. Many SLE
patients develop renal complications.
Laboratory Testing
The presence of autoantibodies
can usually be determined by the antinuclear
antibody (ANA) test performed on patient serum
from blood. The titer, or strength, of the ANA
gives a rough indication of the severity of the
disease. Not all positive ANA tests indicate
autoimmune disease, particularly when the titer is
low. After a positive screening ANA test, more
specific tests for SLE include detection of
autoantibodies to double stranded DNA and to Smith
antigen.
- Antinuclear antibody (ANA)
test with homogenous pattern, Hep2 cell
substrate, FITC immunofluorescence.
- Antinuclear antibody (ANA)
test with rim pattern, Hep2 cell substrate, FITC
immunofluorescence.
- Anti-native DNA test with
Crithidia substrate, FITC immunofluorescence.
Dermatologic Manifestations
Skin rashes are common with SLE.
The most characteristic rash is seen across the
malar region of the face, the so-called "butterfly
rash" that is accentuated by sun exposure. SLE
must be distinguished from discoid lupus
erythematosus (DLE) which affects the skin (but
only in sun exposed regions) and is unlikely to be
associated with systemic illness, such as renal
disease. A biopsy of sun exposed skin that is not
involved with a rash will demonstrate immune
complex deposition with SLE, but not with DLE.
- Systemic lupus erythematosus.
malar rash in a young girl, gross.
- Systemic lupus erythematosus,
skin biopsy, H and E stain, microscopic.
- Systemic lupus erythematosus.
Immunofluorescence of skin with antibody to IgG.
Renal Manifestations
Renal disease is common with SLE
because the immune complexes are often deposited
in the renal glomeruli. A renal biopsy is often
performed to determine the degree of involvement
and determine therapy. Despite therapy,
progression to chronic renal failure is common.
- Systemic lupus erythematosus.
glomerulus, microscopic.
- Systemic lupus erythematosus.
Glomerulus with antibody to C1q,
immunofluorescence.
- System lupus erythematosus.
Glomerulus by electron microscopy.
- Urinalysis in patient with
SLE red blood cell cast, microscopic.
- Urinalysis in patient with
SLE, white blood cell cast, microscopic.
Other Manifestations
Immune complex deposition in
mesothelium can potentiate formation of effusions
in body cavities. Besides pericardial effusions
and serous pericarditis, SLE patients can have a
form of endocarditis called Libman- Sacks
endocarditis. Synovial immune complexes can lead
to arthralgias.
- Systemic lupus erythematosus,
vasculitis in artery, microscopic.
- Systemic lupus erythematosus,
periarteriolar splenic fibrosis, microscopic.
- Systemic lupus erythematosus,
Libman-Sacks endocarditis, gross.
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