Lupus - Systemic Lupus Erythematosus (SLE)

What is Lupus - Systemic Lupus Erythematosus?
Statistics on Lupus - Systemic Lupus Erythematosus
Risk Factors for Lupus - Systemic Lupus Erythematosus
Progression of Lupus - Systemic Lupus Erythematosus
Symptoms of Lupus - Systemic Lupus Erythematosus
How is Lupus - Systemic Lupus Erythematosus Diagnosed?
Prognosis of Lupus - Systemic Lupus Erythematosus
How is Lupus - Systemic Lupus Erythematosus Treated?
Lupus - Systemic Lupus Erythematosus References
Drugs/Products Associated with Lupus - Systemic Lupus Erythematosus

What is Lupus - Systemic Lupus Erythematosus?

Systemic lupus erythematosus (SLE) is an autoimmune disorder that may affect many organ systems within the body. In particular it is associated with a distinctive rash and joint pain, however the most potentially serious problems are due to effects on the brain and kidneys.

Statistics on Lupus - Systemic Lupus Erythematosus

SLE occurs worldwide, but racial differences are seen. It is estimated to affect 1 in every 250 African-American women.

There is a female predominance (9:1), and peak age of onset is between 20-40 years.

The disease affects 0.1-0.2% of the population, and is much more common in Africans.

Risk Factors for Lupus - Systemic Lupus Erythematosus

Cause unknown but probably multi-factorial. Factors thought to be involved:

Genetic: 70% concordance between identical twins and increased incidence of HLA-B8 and HLA-DR3.
Immunological: antinuclear antibodies are present which are thought to result from polyclonal activation of B cells by an antigenic stimulus (possibly viral). May be associated with impaired T cell regulation and deficiencies in complement.
Drugs: hydralazine, isoniazid, anticonvulsants and procainamide may cause a mild lupus like syndrome which often resolves with withdrawal of the drug.
Infection: viral infections may be responsible.
Hormonal factors: high incidence in women suggest female hormones may modify the immune system.
Sunlight is an exacerbating factor for the cutaneous (affecting the skin) manifestations in most cases.

Progression of Lupus - Systemic Lupus Erythematosus

SLE usually occurs in episodes, with flares and remissions that may last for long periods of time. In some patients, it may persist as a chronic illness. Generally speaking, if serious complications have not developed by the first few years, they are unlikely to do so.

Symptoms of Lupus - Systemic Lupus Erythematosus

Features typical of SLE include:

fever
joint pains
fatigue
rash that worsens with sun exposure
mouth ulcers
hair loss
urticaria (hives)

There may have been previous problems with pregnancy (multiple miscarriages), or a family history of autoimmune disease such as rheumatoid arthritis.

Other features may include:

raised blood pressure.
mouth ulcers.
dry eyes
hair loss.
joint tenderness or swelling.
signs of fluid in the lungs.
signs of inflammation of the fibrous sac surrounding the heart (pericarditis).
protein in the urine.
scaly red rash in a 'butterfly' distribution over the face and other sun exposed areas.

How is Lupus - Systemic Lupus Erythematosus Diagnosed?

A combination of clinical and physical findings, plus appropriate tests are needed to make a diagnosis of SLE.

Tests may include:

Blood tests
Immunological tests
Urine testing (protein in the urine suggests kidney involvement)
Biopsy (taking a sample of the skin or kidney to look for abnormalities)
MRI scan to look for involvement of the brain.

Prognosis of Lupus - Systemic Lupus Erythematosus

With current treatments, prognosis is good. Survival rates have increased from 50% at five years during the 1950s, to approximately 90% at 10 years presently.

How is Lupus - Systemic Lupus Erythematosus Treated?

Treatment depends on symptoms and severity of the disease.

NSAIDs - useful for mild disease with arthralgia
Hydroxychloroquine - mild disease when symptoms cannot be controlled with NSAIDS or for cutaneous disease.
Corticosteroids - mainstay of treatment. Particularly for moderate to severe disease. Aim is to control disease activity before gradually reducing the dose.
Immunosuppressives (azathioprine, cyclophosphamide) - usually in combination with corticosteroids for severe disease (e.g. renal or cerebral disease).
Topical steroids - for discoid lupus. Should also avoid excessive sunlight (suncream and clothing).

Lupus - Systemic Lupus Erythematosus References

Braunwald, Fauci, Kasper, Hauser, Longo, Jameson. Harrison's Principles of Internal Medicine. 15th Edition. McGraw-Hill. 2001
Cotran, Kumar, Collins 6th edition. Robbins Pathologic Basis of Disease. WB Saunders Company. 1999.
Hurst JW (Editor-in-chief). Medicine for the practicing physician. 4th edition Appleton and Lange 1996.
Kumar P, Clark M. CLINICAL MEDICINE. WB Saunders 2002 Pg 427-430.
Longmore M, Wilkinson I, Torok E. OXFORD HANDBOOK OF CLINICAL MEDICINE. Oxford Universtiy Press. 2001