Systemic Lupus Erythematosus and related antibodies

It's not Lupus. It's never Lupus.

Hey everyone!
This blog covers the various auto-antibodies related to Lupus. Auto-antibodies only.
Let's get started ^__^

What is Systemic Lupus Erythematosus?
It is an autoimmune disease, in which the immune system attacks the body's cells and tissues, resulting in inflammation and tissue damage.

SLE is a hypersensitivity type II and type III mediated autoimmunity.
That means, organs, tissues & cells undergo damage mediated by tissue-binding auto-antibodies and immune complexes.
"It's never Lupus" -Dr. House
"But.. What if it's Lupus?" -Me
First we'll have to screen the patient..
Antinuclear Antibodies are sensitive but not specific for SLE.
ANA screening yields positive results in many connective tissue disorders and other autoimmune diseases, and may occur in normal individuals.

Then we'll have to decide whether it's really Lupus or something else..
Anti-Smith Antibodies is the most specific for SLE.
(LSm proteins are a family of RNA-binding proteins found in virtually every cellular organism.)
If Anti-Sm is present, patient has Lupus, no doubt about it. Very specific.

We'll have to figure out what is the prognosis..
Antibodies to dsDNA are highly specific for SLE; they are present in 70% of cases. It indicates poor prgonosis. High titres of anti-dsDNA antibodies are associated with development or progression of lupus nephritis.

Is the lupus due to drugs?
Antihistone Antibody has a sensitivity of 50%-70% in detecting patients with SLE and more than 95% sensitivity in detecting patients with drug-induced LE.

Did you know?
Lupus Anticoagulant is an antiphospholipid antibody which cross reacts with Cardiolipin in Syphilis tests (RPR/VDRL) giving a false positive for Syphilis.
[Note: Anticardiolipin antibody (aCL) is also an antiphospholipid antibody which is closely related to lupus anticoagulant (LA)]

That's all!

Now you know which antibody is for what if it is Lupus =D

Link to Lupus flashcards