Comportamento das curvas resultantes da interação das leituras visuais e digitais na triagem de auto-anticorpos (FAN) pela imunofluorescência indireta

Abstract

The indirect immunofluorescence test is widely used in the clinical pathology laboratory. Among the tests in this group we have FAN, which means research of antibodies against components of the nucleus, nucleolus, cytoplasm and mitotic spindle. This test, used in the selection of auto antibodies, imposes some difficulties for its application such as: it requires two highly specialized technicians to read of the slides, what prevents automation of the process; low standardization; lack of documentation; decay of the fluorescence while reading of the slide; lack of standardization of the optic system; great variability of substrata and the dependence on the experience of the observer. These factors limit the use of the test to a small group of laboratories worldwide. This work aims at minimizing those difficulties by creating the basic knowledge on the behavior of the resultant curves of the interactions between visual and digital readings. The images visual read are digitally captured and the intensity of its fluorescent green is evaluated. We analyze the curves produced for five patterns of FAN: homogeneous nuclear pattern, speckled centromeric nuclear pattern, mixed fine speckled nuclear standard and mitotic spindle NuMa 1, mitotic spindle pattern NuMa 2 and nucleolar homogeneous pattern. The behavior of the resultant curves of the interaction of digital and visual readings shows that the digital readings within a single title in the same patterns can be differentiated in 96,7% of the cases. In a second within patterns analysis, homologous dilutions, with several titles in the same pattern were distinguished in 99,2% of cases. The inter patterns analysis, which assesses whether the calibration curve obtained using homogeneous nucleolar pattern can be used for the others patterns, we obtained 98,8% of concordance. The creation of a new technology through knowledge of the behaviors of the resultant curves of the visual and digital readings of FAN testes can cause what we call “technological unemployment”, this phenomenon can be aggravated if society is in a decreasing economic cycle. In Brazil there is a group of public policies theat guide the application of a fund to support worker qualification minimizing the impact caused by the introduction of a new technology.