[Evaluation of a new commercial latex test for the study of rheumatoid factors].

A new commercial test of IgG-sensitized latex particle agglutination is compared with a long-established latex test for detection and titration of rheumatoid factors. The comparison was conducted on samples from three groups of patients: 125 with seropositive rheumatoid arthritis (RA), 115 seropositive samples from patients with various diseases except RA, and 100 seronegative samples with varying diagnosis including RA. The new test is very simple to perform. Its sensitivity, however, was lower than that of the Rheins test by about 2.5 dilutions. Its specificity as to the diagnosis of RA was significantly better than that of the Rheins test.