Fluorescent treponemal antibody absorption test

Positive finding of antiphospholipid antibodies based on (1) an abnormal serum level of IgG or IgM anticardiolipin antibodies, (2) a positive test result for lupus anticoagulant using a standard method, or (3) a false-positive serologic test for syphilis known to be positive for at least 6 months and confirmed by Treponema pallidum immobilization or fluorescent treponemal antibody absorption test. 

Treponemal tests are more sensitive than nontreponemal tests and are used to confirm the diagnosis (i.e., the fluorescent treponemal antibody absorption). 

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