ANTINUCLEAR ANTIBODY TESTING IN A REFERRAL LABORATORY

Antinuclear antibody (ANA) testing, consisting of the immunofluorescen t ANA (FANA) and ANA profile, is an integral part of the evaluation of the patient who is suspected of having connective tissue disease. We reviewed the results of FANA and ANA profile testing from more than 8, 000 serum samples to examine the relationships between these tests. Fi fty-two percent of referred serum samples had a positive ANA test resu lt and 19% of samples had a positive ANA profile. Nine percent of the serum samples bad a positive ANA profile result despite a negative FAN A test result. Although the routine FANA test is considered the ''gold standard'' for sensitive detection of connective tissue disease, scre ening with an FANA test may not detect diseases associated with anti-S SA/Ro, anti-double-stranded DNA, or anti-extractable nuclear antigen a ntibodies. Comparison of subgroups of specific antibodies support the validity of autoantibodies as markers for diseases or subgroups of con nective tissue disease.