Systemic Lupus Erythematosus - Treatment

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As with the ANA, these antibodies have a tendency to appear and disappear. Patients who have these autoantibodies as well as blood clotting problems or frequent miscarriages are diagnosed with antiphospholipid syndrome (APS), which often occurs in SLE but can also develop independently.

Other Blood Tests

Complement. Blood tests of patients with SLE often show low levels of serum complement, a group of proteins in the blood that aid the body's infection fighters. Individual proteins are termed by the letter "C" followed by a number. Common complement tests measure C3, C4, C1q, and CH50. Complement levels are especially low if there is kidney involvement or other disease activity.

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Blood Count. White and red blood cell and platelet counts are usually lower than normal and, depending on severity, are used to determine complications, such as anemia or infection.

Erythrocyte Sedimentation Rate (ESR). An erythrocyte sedimentation rate (ESR or sed rate) measures how fast red blood cells (erythrocytes) fall to the bottom of a fine glass tube that is filled with the patient's blood. A high sed rate indicates inflammation.

C-Reactive Protein (CRP). High levels of this blood protein indicate inflammation. Like the ESR, the CRP test cannot tell where the inflammation is located or what is causing it.

Click the icon to see an image of the formed elements of blood.

Skin Tests

If a skin rash is present, the doctor may take a biopsy (a tissue sample) from the margin of a skin lesion. A test known as a lupus band detects immunoglobulin G (IgG) antibodies, which are located just below the outer layer of the tissue sample. They are much more likely to be present with active SLE than with inactive disease.

Tests for Complications of SLE

Kidney Damage and Lupus Nephritis. Kidney damage in patients already diagnosed with SLE may be detected from the following tests:

• Blood tests that measure creatinine, a protein metabolized in muscles and excreted in the urine. High levels suggest kidney damage, although kidney problems can also be present with normal creatinine levels.
• Urine tests to measure protein levels
• Tests for detecting anti-ds DNA antibodies and blood complements.
• A kidney biopsy may be performed to evaluate the extent of kidney damage.

Lung and Heart Involvement. A chest x-ray may be performed to check lung and heart function. An electrocardiogram and an echocardiogram are administered if heart disease is suspected.

Click the icon to see an image of an electrocardiogram.

Review Date: 02/18/2011
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org).