Lupus Erythematosus, Systemic

Risk: Risk factors include sex, race, heredity, and exposure to certain medications or viruses. Sex hormones appear to play some role because most cases develop during the childbearing years. In the US, black women appear to be at increased risk. Family members of affected individuals may also be at increased risk. Approximately 90% of individuals with SLE are young women in their late teens to 30s, but the disease can also affect children (primarily girls), older women, and men (Schumacher 378). Drug-induced lupus affects men and women equally.

Incidence and Prevalence: On average, about 1 in 10,000 people in the US get lupus every year (Hildebrand). More people have lupus than AIDS, multiple sclerosis, cerebral palsy, sickle cell anemia, and cystic fibrosis combined (Batiste). The condition is considered more common in China, in Southeast Asia, and among blacks in the Caribbean.

History: The severity of symptoms varies in different individuals and within the same individual over time. Early symptoms may include joint or muscle pain, fever, or migraine-type headaches. Individuals may also report loss of appetite (anorexia); abdominal pain; swollen glands; sensitivity to cold in the fingers, toes, nose, and ears (Raynaud's phenomenon); feelings of stress and anxiety; weight loss; or a general feeling of ill health (malaise). Visual disturbances may occur, including over-sensitivity to light (photophobia) or blurred vision. The person may feel pain when taking deep breaths. Most individuals will complain of a skin rash at some time, particularly after exposure to sunlight.

Physical exam: The hallmark symptom of SLE is the characteristic red, blotchy, butterfly-shaped rash over the cheeks and bridge of the nose. Individuals with SLE may also present with ulcers in the mouth, hair loss, and red, swollen, painful joints. If more systems are involved, symptoms are related to inflammation in the involved organs. Common findings include inflammation of the lining of the lungs (pleurisy) and of the membrane surrounding the heart (pericarditis). Scattered abdominal tenderness may be due to inflammation of the membrane lining the abdominal cavity that is not related to infection (sterile peritonitis). High blood pressure (hypertension) and ankle swelling (peripheral edema) are the most common indications of kidney involvement (renal disease).

Tests: No one test can determine lupus, but various laboratory tests can help confirm the diagnosis. Anemia detected on a complete blood cell count (CBC) may be caused by chronic inflammation, renal disease, or destruction of red blood cells (hemolysis). Increased urea nitrogen or creatinine on a blood chemistry or an abnormal urinary sediment indicates kidney involvement. Blood tests used to detect specific antibodies include ANA (antinuclear antibody test), the anti-DNA antibody test, the anti-Sm antibody test, and complement levels. Removal of tissue for microscopic examination (skin biopsy) can also detect antibodies that occur when the disease is active. X-rays of painful joints, muscle testing through electromyography (EMG), and microscopic examination of fluid withdrawn from the joints may be done to rule out other disease processes. Chest x-rays may be taken to detect lung damage, and an electrocardiogram (ECG) can detect heart problems. CT or MRI can be used to evaluate CNS involvement.