Systemic lupus erythematosus: clinical presentations.

Systemic lupus erythematosus is a complex multisystem autoimmune disease that affects 1 in 2000 adult women in the United Kingdom. Lupus affects Afrocaribbeans and South Asians more frequently and more severely than white British. The disease can affect almost any part of the body and is characterised by remission and relapses. It is most common in women of reproductive age but can present at any age from 1 to 90 years and in men, but the diagnosis is probably missed in some men. It is important to distinguish active lupus features due to inflammatory and thrombotic mechanisms from chronic damage and to be aware that infection is an important trigger that may co-exist or mimic lupus activity. The disease is associated with a variety of autoantibodies that can help in making the diagnosis. Monitoring the disease is usually done using a clinical disease activity index such as the BILAG index, anti-dsDNA antibodies, C3 and C4 levels. Anti-C1q antibodies may have a role in monitoring the disease and in predicting those at risk of renal involvement or flare. The prognosis depends on the organs involved. There is an increased risk of premature atherosclerosis as a complication of lupus and this and infection are the most common causes of death in lupus patients.