Lupus

Lupus erythematosus (also known as systemic lupus erythematosus or SLE) is an autoimmune disorder in which antibodies are created against the patient's own DNA. It can cause various symptoms, but the main ones relate to the skin, kidney (lupus nephritis), joints, blood and immune system.

It is named for the Latin lupus, meaning "wolf", perhaps due to a crude similarity between the facial rash associated with the illness, and a wolf's face, although various explanations exist.

Signs and symptoms
Common initial and chronic complaints are fever, malaise, joint pains, myalgias and fatigue. Because they are so often seen with other diseases, these signs and symptoms are not part of the diagnostic criteria for SLE. When occurring in conjunction with other signs and symptoms, however, they are considered suggestive.

Diagnosis
Some physicians make a diagnosis on the basis of the ACR classification criteria (see below). The criteria, however, were established mainly for use in scientific research (i.e. inclusion in randomised controlled trials), and patients may have lupus despite never meeting the criteria.

Antinuclear antibody testing and anti-extractable nuclear antigen (anti-ENA) form the mainstay of serologic testing for lupus. Antiphospholipid antibodies occur more often in SLE, and can predispose for thrombosis. More specific is the anti-smith antibody. Other tests routinely performed in suspected SLE are complement system levels (low levels suggest consumption by the immune system), electrolytes and renal function (disturbed if the kidney is involved), liver enzymes and a full blood count.

Treatment
SLE is a chronic disease with no cure. There are, however, some medications, such as corticosteroids and immunosuppressants which can control the disease and prevent flares. Flares are typically treated with steroids, with DMARDs (disease-modifying antirheumatic drugs) to suppress the disease process, reduce steroid needs and prevent flares. DMARDs commonly in use are the antimalarials (e.g. hydroxychloroquine) and azathioprine. Cyclophosphamide is used for severe nephritis or other organ-damaging complications.

Patients who require steroids frequently may develop obesity, diabetes and osteoporosis. Hence, steroids are avoided where possible.

Measures such as avoiding sunlight (to prevent problems due to photosensitivity) may also have some effect.

Other immunosuppressants and autologous stem cell transplants are under investigation.