Management of Systemic Lupus Erythematosus

SLE is the commonest connective tissue disease encountered in clinical practice. It is a multisystem disorder which can involve the skin, mucous membranes, joints, lungs, kidneys, central and/or peripheral nervous system, heart, and the gastrointestinal system. Constitutional features of fever, fatigue, anorexia and weight loss are common. Lupus should be suspected in the following clinical settings: 1. Multisystem involvement in a young female 2. Inflammatory polyarthritis with additional features like fever, prominent mucocutaneous involvement, active urine sediment, cytopenias, and neuropsychiatric features 3. FUO (Fever of unknown origin) 4. Unexplained renal failure/nephrotic syndrome 5. Polyserositis 6. Mononeuritis multiplex 7. Psychosis in a young female 8. Picture of ITP (idiopathic thrombocytopenic purpura) with splenomegaly. SLE is characterized by the presence of antinuclear antibodies (ANA). Indirect immunofluorescence continues to be the gold standard for detection of ANA. Since low titre ANA are seen in nearly 5% healthy young women, interpretation of autoantibody results should always be in context of the clinical picture. Certain ANA subsets such as dsDNA (sensitivity 50-60%) and Sm (sensitivity 30%) are highly specific for SLE. Antibodies to ds DNA should not be used as a screening test for SLE. The major utility is in confirmation of the diagnosis of lupus in ANA positive individuals. Also, dsDNA levels generally correlate with disease activity especially in lupus nephritis. In an occasional patient, the dsDNA levels may not parallel disease activity, the so called “clinico-serologic discordance”. In such cases the dictum is to treat the patient and not chase the dsDNA levels.