Graduate Project - Antinuclear Antibodies (ANAs) – Diagnosing Lupus

Hello again,

After my post on diagnosing Lupus I recieved a lot of questions on using Antinuclear Antibodies (ANAs) to diagnose Lupus so that’s what we will cover in this post.

The primary test for SLE is Antinuclear Antibodies (ANAs) which checks for antinuclear antibodies that attack the cell nucleus. High levels of ANA are found in more than 98% of patients with SLE. However there are other conditions that may cause high levels of ANA, so a positive test is not a definite diagnosis for SLE. Other diseases are scleroderma, Sjögren syndrome, or rheumatoid arthritis. ANAs may also be weakly present in about 20 - 40% of healthy women. Drugs such as hydralazine, procainamide, isoniazid, and chlorpromazine can also produce positive antibody tests. A negative ANA test makes a diagnosis of SLE unlikely but not impossible. High or low concentrations of ANA also do not necessarily indicate the severity of the disease, since antibodies tend to come and go in patients with SLE.

In general, the ANA test is considered a screening test. If SLE-like symptoms are present and the ANA test is positive, other tests for SLE will be administered. If SLE-like symptoms are not present and the test is positive, the doctor will look for other causes, or the results will be ignored if the patient is feeling healthy.

Antinuclear Antibodies (ANAs) Pattern seen in SLE:

Homogeneous (Diffuse)

• Uniform fluorescence of entire nucleus with or without masking of nucleoli


• Chromosome region of metaphase mitotic cells positive with smooth or peripheral staining intensity greater than or equal to interphase nuclei

Also, additional, more specific tests, such as the anti-double strand DNA (dsDNA) and anti-smith antibodies (Sm), are used to confirm the diagnosis of lupus.

Tests used to diagnose SLE may include:

• Antibody tests, including antinuclear antibody (ANA) panel


• CBC


• Chest x-ray


• Kidney biopsy


• Urinalysis

Remember, no one test can diagnose or rule out the disease and one would have to present with at least 4 of the 11 typical.

Malar rash – a rash over the cheeks and nose, often in the shape of a butterfly

Discoid rash – a rash that appears as red, raised, disk-shaped patches

Photosensitivity – a reaction to sun or light that causes a skin rash to appear or get worse

Oral ulcers – sores appearing in the mouth

Arthritis – joint pain and swelling of two or more joints in which the bones around the joints do not become destroyed

Serositis – inflammation of the lining around the lungs (pleuritis) or inflammation of the lining around the heart that causes chest pain which is worse with deep breathing (pericarditis)

Kidney disorder – persistent protein or cellular casts in the urine

Neurological disorder – seizures or psychosis

Blood disorder – anemia (low red blood cell count), leukopenia (low white blood cell count), lymphopenia (low level of specific white blood cells), or thrombocytopenia (low platelet count)

Immunologic disorder – abnormal anti-double-stranded DNA or anti-Sm, positive antiphospholipid antibodies

Abnormal antinuclear antibody (ANA)

Hopefully this post added to your wealth of knowledge on SLE.

Thanks for reading comment and post!!!