ANA antibodies target nuclear components of cells and are commonly present in autoimmune disorders.

The indirect immunofluorescence (IF) method is considered the gold standard for ANA detection.

Clinical uses include:

Supporting diagnosis of systemic lupus erythematosus (SLE).

Detecting other autoimmune diseases such as Sjögren’s syndrome, scleroderma, mixed connective tissue disease, and rheumatoid arthritis.

Differentiating autoimmune causes of chronic symptoms like fatigue, joint pain, or rashes.

The test is performed using a blood sample, with results reported as titers and fluorescence patterns (homogeneous, speckled, nucleolar, centromere, etc.).

Analyte: Antinuclear antibodies in serum.

Normal Result: Negative (no detectable ANA).

Abnormal Findings:

Positive ANA: Suggests autoimmune disease; pattern and titer provide diagnostic clues.

High titers: Stronger association with active autoimmune disease.

Clinical Use:

Provides a screening tool for autoimmune disorders.

Guides further testing (e.g., anti-dsDNA, ENA panel) based on ANA positivity and fluorescence pattern.

Helps monitor disease activity in certain autoimmune conditions.