[Serological diagnosis of systemic connective tissue inflammation; a new immunofluorescence method for demonstrating antinuclear antibodies]. / La diagnosi sierologica delle connettiviti sistemiche; un nuovo metodo d'immunofluorescenza per la dimostrazione di anticorpi antinucleari.

Two methods for the demonstration of antinuclear antibodies by means of indirect immunofluorescence were employed on 83 serum samples from 80 patients, with rat liver as the substrate. The first method (the classic ANA-test) uses cryostatic slices fixed in acetone; the second (ANA-Bp-test) is based on fixation of the substrate with Bouin's fluid and embedding in paraffin. The series was composed of 25 cases of lupus erythematosus (28 serum samples), 10 of rheumatoid arthritis, 1 of dermatomyositis, 8 of progressive systemic sclerosis, 4 of unclassifiable systemic connective tissues diseases, and 28 various internal and rheumatological forms. The undiluted sera that proved positive were subsequently tested for Ig typing and ANA titration. The ANA-Bp-test was found to be more sensitive, safer, more practical and less expensive than the ANA-test.