Update on the immunology, diagnosis and management of systemic lupus erythematosus.

Lupus occurs with a prevalence of 2-9 in 10,000 people, targeting female and indigenous populations in particular. Lupus and related systemic autoimmune syndromes (scleroderma, Sjögren's syndrome, rheumatoid arthritis and polymyositis) result from a similar set of genetically and environmentally modulated immune disturbances, and the diagnostic and management approach to these conditions is broadly comparable. Evanescent, vague symptoms, restrictive diagnostic criteria and low diagnostic suspicion might have resulted in the under-diagnosis of these problems in the past, imposing considerable burdens on sufferers and the community. Serological screening should be employed cautiously and wisely, given the rapidly occurring changes in methodology, which have lowered their specificity. Close liaison with the immunology laboratories performing these tests is therefore advisable. Clinicians should emphasize the improving prognosis of lupus and related conditions as a result of earlier disease detection, improved educational support systems and refined medical therapies.