Definition and significance of high positivity aCL ELISA.

We conducted a prospective study of anticardiolipin antibody (aCL) testing, performed in our university hospital. Among 6321 consecutive patients tested for both IgG and IgM aCL, 91 patients with medium or high positivity (>99th percentile) had a subsequent confirmatory test. Among them, 53 had a persistent positivity at 12 weeks. In this real world setting, patients with transient positivity had lower values than patients with persistent positivity. Lupus (2012) 21, 725-726.