ANA Anti-Nuclear Antibodies

Purpose of this Test

The ANA (Antinuclear Antibody) Screen, IFA, Blood Test with Reflex to Titer and Pattern is used to detect antinuclear antibodies, which can assist in identifying autoimmune disorders. These antibodies are a specific type of immune protein that, instead of defending the body against harmful invaders like infections, mistakenly attack the body’s own cells.

The term “antinuclear” refers to these antibodies targeting the nucleus of cells, which is the central hub responsible for controlling cell activities. When these antibodies wrongly identify proteins in the nucleus as harmful, they cause the immune system to trigger inflammation, leading to self-attacks on healthy tissues. While it is normal for small amounts of these antibodies to be present, particularly in older adults, an increased presence could suggest an autoimmune condition.

This test is especially helpful in diagnosing autoimmune diseases like:

• Lupus (SLE)
• Sjogren’s syndrome
• Polymyositis or dermatomyositis
• Juvenile arthritis
• Raynaud’s phenomenon
• Drug-induced lupus
• Mixed connective tissue disease
• Autoimmune liver diseases

When to Consider this Test

An ANA-IFA Blood Test may be useful if an individual exhibits signs of an autoimmune disorder. Common indicators include:

• Persistent fever
• Skin rashes
• Chronic fatigue
• Joint pain or swelling
• Muscle aches
• Digestive discomfort or abdominal issues
• Swollen lymph nodes

Understanding the Results

A negative ANA result means that no autoantibodies were detected, making it unlikely that the individual has an autoimmune condition.

A positive result suggests that autoantibodies are present, which could point to an autoimmune disease. However, having a positive ANA test doesn’t always confirm an autoimmune disorder. It can sometimes result from infections, certain medications, or other medical conditions, including cancer. Therefore, doctors will interpret the ANA test alongside a patient’s clinical symptoms, physical examination findings, and additional lab results to form a comprehensive diagnosis.

This test also measures the antibody titer, which indicates how concentrated the antibodies are in the blood, expressed as a ratio (e.g., 1:160). The cutoff for a positive titer varies depending on the laboratory. Additionally, the test reveals the staining patterns formed by the antibodies, which can help guide the healthcare provider on whether more tests are needed. Specific patterns are often linked to different autoimmune diseases. These patterns include:

• Uniform (homogeneous)
• Speckled
• Centromere-focused
• Nucleolar