Systemic Lupus Erythematosis (SLE)

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1. What is Systemic Lupus Erythematosis?
Systemic lupus erythematosus or SLE is one of a group of illnesses called autoimmune diseases. The immune system is the bodies defence against attack by foreign organisms like viruses and bacteria.  One of the ways that the immune system works is by producing antibodies which are molecules that stick to foreign proteins and allow the cells of the immune system to destroy them.  Sometimes, the immune system starts to make antibodies that stick to the bodies own cells.  These antibodies are called autoantibodies and when they stick to the bodies own cells they cause an inflammatory reaction and can damage the cells.

SLE is called "systemic" because its effects can show in many parts of the body; "lupus" is refers to a type of skin rash and "erythematosis" means "red".   SLE can produce all sorts of symptoms and can imitate many other diseases. Many patients with SLE have pain and swelling in the joints; fatigue, fever, chills, and headache.  It is very common to have a skin rash in SLE and this comes in several guises

Discoid Lupus Erythematosus. About one fifth of patients have round lesions (discoid) that are raised and scaly.  Untreated, these lesions grow and can cause severe scarring. Discoid lesions are often associated with a rash across the face.

Vasculitis. Inflamed blood vessels (vasculitis) may cause red marks in any area of the body. Sometimes deep red lumps appear, especially on the leg, where they may develop into ulcers. In some people, reddish-purple lesions appear on the tips of the fingers and toes.

90% of patients with SLE are women and it is commoner before the menopause.  There is a genetic component to SLE because there is a higher risk of developing SLE if a close family member also has it. 

2. How is SLE diagnosed?
The most reliable method is a blood test that looks for specific antibodies to components that are normally found inside cells.  One antibody is called anti dsDNA and is fairly specific to SLE, and another is called anti SM.

3. How is SLE treated?
Unfortunately there is no cure for most autoimmune diseases and SLE is no different.  Treatment is usually aimed at reducing the immune response using drugs such as steroids.  However, treatment has to be tailored to the individual and the advice of a specialist is required.

4. What is the prognosis for SLE?
SLE is a chronic, life-long condition that is characterised by periods of remission and relapse.  The course in any individual is difficult to predict but with modern treatment most patients have a normal lifespan.

S.R.Dodds 2001