OBJECTIVE: To evaluate the prevalence of patterns and titers of antinuclear antibodies (ANA) detected by indirect immunofluorescence (IIF) technique on HEp-2 cells in a university hospital following the introduction of I and II Brazilian Consensuses for Standardization of ANA in HEp-2 Cells. METHODS:A transversal study was performed between 2002 and 2005 during which all ANA orders to Serviço de Hospital de Clínicas de Porto Alegre (SPC/HCPA) and cognate results were reviewed. RESULTS:12.095 tests of ANA were revised. The number of positive results during this period was 2.577 (21.30%), annual mean 644 (SD: 233). A marked increase in the number of positive results was observed following the introduction of the Consensuses (p < 0.001). Rheumatology was the medical specialty which requested the highest number of ANA testing per patient although a significant decrease of these numbers was observed after the introduction of the Consensus in 2004 (p < 0,001). Nuclear fine speckled immunofluorescence labeling was the most frequently ANA pattern observed, 52.3% (453/866), and low ANA titers (1/80 and 1/160) more commonly detected (27.8% and 29.4%, respectively). CONCLUSION: Following the introduction of the Brazilian Consensus for standardization of ANA in HEp-2 cells an increased number of positive results was observed, mostly in low titers and with nuclear fine speckled immunofluorescence pattern. Moreover, there were decreasing numbers of ANA orders by rheumatologists in the same period. Potential causes for these observations are discussed but the real impact in the clinical condition of the patient and therapy deserves to be better studied.
autoantibody; antinuclear antibodies; HEP-2 cells; indirect immunofluorescent
