ANA by IFA, Reflex to 9-biomarker profile, dsDNA, RNP, Sm, SS-A, SS-B, Scl-70, Chromatin, Jo-1, Centromere B by Multiplex Immunoassay

Serum

1 mL

0.5 mL

Red-top tube or gel-barrier tube

Assay for screening for ANAs in patients suspected of having connective tissue disease.

Males and females older than 80 years of age have a 50% incidence of low titer ANA. Various medications can induce a "lupoid" condition and elevated ANA titers. Usually the titer decreases following removal of the drug. Low antibody levels may be found in diseases other than connective tissue disease.

Indirect immunofluorescence assay (IFA) and multiplex flow immunoassay

The indirect immunofluorescent test has three elements to consider in the result:

1. Positive or negative fluorescence. A negative test is strong evidence against a diagnosis of SLE but not conclusive.

2. The titer (dilution) to which fluorescence remains positive (provides a reflection of the concentration or avidity of the antibody). Many individuals, particularly the elderly, may have low titer ANA without significant disease substantiated after work-up.

3. The pattern of nuclear fluorescence (reflecting specificity for various diseases).

Cytoplasmic (non-nuclear) staining patterns may also be noted with the IFA methodology.

Multiplex ANA detects up to 11 specific antibodies of the 100+ antibodies that may be found in the ANA IFA.