[The optimization of techniques complex of serologic diagnostics of connective tissue systemic diseases].

The connective tissue systemic diseases originate from pathologic process following with antinuclear antibodies emergence. To detect these antibodies a significant number of diagnostic tests and techniques has been applied. Besides that, there is no conventional algorithm of antinuclear antibodies diagnostic. To detect antinuclear antibodies a two-fold diagnostic algorithm was applied In the capacity of screening techniques the indirect immunofluorescence technique was applied to the cells of line Hep-2 (antinuclear factor) and detection of antibodies to extractable nuclear antigen. The second stage of diagnostic included the detection of content of more specific antinuclear antibodies using the Lineblott method and the double-helical DNA antibodies. The blood serum from 981 patients with suspected connective tissue systemic diseases, 115 patients with systemic lupus erythematous and 57 healthy individuals was analyzed. The levels of antinuclear factor, nuclear antigen antibodies and double-helical DNA antibodies were detected. The antinuclear factor was detected in 84% and 86% of cases, double-helical DNA antibodies in 55% and 39% of cases depending of reagents using in detecting these characteristics. Among healthy individuals, antinuclear factor was detected in 5% (1/20) of blood serum samples in titers less than 1:160. In the group of patients with suspected connective tissue systemic diseases, antinuclear factor was detected in 48% (474/981) of cases and extractable nuclear antigen in 20% (326/981) of cases. The Lineblott test was positive in 33% (326/981) of patients with suspected connective tissue systemic diseases. Among antinuclear factor positive patients nuclear antigen antibodies were detected in 36% (171/474) and the Lineblott test was positive in 63% (298/474) of cases. Among antinuclear factor negative patients but positive under anti-nuclear antigen identification, the Lineblott test was positive in 6% (28/507) of cases. The two-fold algorithm of nuclear antigen testing is an effective technique to be applied in the clinical diagnostic laboratory. The results of effectiveness of this algorithm demonstrated that this method can ensure 33% of cost savings of testing individuals with higher incidence of diseases.