The tradicional fluorescent antinuclear antibody test (ANA) has required constant update efforts from personel involved in performing and interpreting its results. The methodological advances have brought up a considerable improvement in the test’s sensitivity and, consequentely, a decrease in its specificity. This has resulted in an increasing number of positive tests in apparently healthy subjects. However, there are some peculiar features associated with the auto-antibodies in patients with autoimmune diseases that are not present in those observed in healthy subjects. The objective of the present review is to bring an approach on the most important points to be considered in the analysis and evalution of an ANA test that might help in the identification of patients with autoimmune disease. Title and immunofluorescence pattern are discussed as important parameters and they are important in the evaluation of ANA and in the reflex demand for further tests for specific autoantibodies. The basic concepts of the National Consensus on Standardization of ANA-HEp-2 Report are posted. Finally, we explore the possible meanings of a positive ANA test in a patient without objective evidence of autoimmune disease.
Antinuclear antibodies; HEp-2 cells; Autoantibodies; Autoimmune diseases; Serological markers
