Application value of antinuclear antibody spectrum detection in diagnosis of autoimmune diseases

Objective To investigate the application value of the combination detection of the serum antinuclear antibody(ANA) measured by the indirect immunofluorescence(IIF) and the antinuclear antibodies(ANAs) measured by Western blot(LIA) in diagnosing autoimmunity diseases(AID).Methods 436 patients were selected,including 271 patients with autoimmune diseases and 165 patients with non-autoimmune diseases.Serum ANA and ANAs were measured in all patients at the same time.The two detection methods produced four kinds of results:IIF(+)/LIA(+),IIF(-)/ LIA(-),IIF(+)/ LIA(-) and IIF(-)/ LIA(+).Results Among 436 specimens,the results of IIF(+)/ LIA(+) accounted for 40.15%,IIF(-)/ LIA(-) for 25.52%,IIF(+)/ LIA(-) for 15.27%,and IIF(-)/ LIA(+) for 9.81%.The coincidence rate of IIF and LIA results detecting ANA was 65.67%.The positive rates of ANA and ANAs in the patients with autoimmune diseases were 65.3% and 57.9%,obviously higher than 17.6% and 20.0% in the patients with non-autoimmune diseases.The difference in positive rates of ANA and ANAs between the autoimmune disease group and the non-self-immune disease group had statistical significance(P0.01).The correlation of the results of two detection methods only existed in MCTD and SLE patients(P0.01),but without correlation among the other observation groups(P0.05).Conclusion IIF detecting ANA will easily miss some AID patients with positive ANA-specific antibodies,while ANAs detection will also easily lead to ANA of AID patients missed because of its limitation in detecting the number of antibody.So the IIF-ANA and LIA-ANAs detection can not substitute each other.The patient specimens which need to exclude AID by detecting ANA should use the IIF-ANA and LIF-ANAs detection at the same time,to avoid AID patients′missed diagnosis when only one method is used to detect.The IIF method of ANA will easily lead to ANA false-negative in the patients with the primary antibodies of anti-SSA,anti-SSB and anti-Ro52.Due to the incomplete detection of antibodies,the specific ANAs detection of LIA method can not replace the IIF method.The two ANA detection methods can not replace each other,but should be combined in clinical practice work.