Étude d'un test dot-blot de recherche des anticorps anti-antigènes nucléaires solubles

Abstract

To evaluate the place of a recent dot blot technique using native and recombinant antigens (Innolia ® ANA, Ingen France) in the anti-ENA screening scheme, 2210 tests were performed during 18 months : 1600 with the first type of test and 610 with the Update test. All the positives and some of the negatives were compared with an Elisa test using purified bovine antigens (ENA LISA ®, BMD France). The first type of test was in poor agreement for anti-SSA/SSB antibodies and anti-Scl-70 antibodies. The Innolia ® ANA Update was better in concordance : anti-SSA/SSB antibodies 95%, anti-SmRNP antibodies 60%, anti-centromere B antibodies 91%. This test, allowing the identification of thirteen differents autoantibodies was in good agreement with Elisa : 153 dot negative serum were Elisa tested and only six (from 4 patients known and treated for SLE and Scleroderma) were Elisa positive. The possibility of identifying the fine specificities of anti-Ro SSA antibodies (52 and 60 kD) and of anti-Sm/RNP antibodies (SmD, SmB, RNP 70 kD, A or C) will allow a better diagnosis ; some complementary studies are necessary to appreciate the clinical utility of these fine specificities for the patient's follow-up.